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Lingeman DG, O'Dell KL, Syed Z. Developing attractants and repellents for ticks: promises and challenges. CURRENT OPINION IN INSECT SCIENCE 2024; 63:101181. [PMID: 38401667 PMCID: PMC11139562 DOI: 10.1016/j.cois.2024.101181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/18/2024] [Accepted: 02/20/2024] [Indexed: 02/26/2024]
Abstract
Historically, some of the most effective tools to counter vector-borne diseases have been those directed against the vectors. Ticks are undergoing a population explosion as evidenced by the recent expansion of their distribution range. Tick control has traditionally relied heavily on pesticides. However, sustained use of acaricides is resulting in resistant tick populations. Multipronged management strategies that build and expand upon innovative control methods are sorely needed. Behavior-modifying chemicals, referred to as semiochemicals, such as pheromones and repellents, offer a first line of personal protection against ticks. We review the current understanding of tick semiochemicals, and how such understanding is leading to the identification of novel chemistries that are effective and safe.
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Affiliation(s)
- Daniel G Lingeman
- Department of Entomology, University of Kentucky, Lexington, KY 40546, USA
| | - Kenneth L O'Dell
- Department of Entomology, University of Kentucky, Lexington, KY 40546, USA
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2
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Wężyk D, Romanek W, Małaszewicz W, Behnke JM, Bajer A. Mixed-sex clusters on grass blades: breeding strategy of the ornate dog tick, Dermacentor reticulatus. Parasit Vectors 2024; 17:58. [PMID: 38336751 PMCID: PMC10854131 DOI: 10.1186/s13071-024-06129-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Accepted: 01/10/2024] [Indexed: 02/12/2024] Open
Abstract
BACKGROUND The ornate dog tick Dermacentor reticulatus is second only to the hard tick Ixodes ricinus in terms of importance as a vector of infectious organisms, especially of Babesia canis, the agent of canine babesiosis. Both the geographical range and local densities of D. reticulatus are steadily increasing in many regions of Europe. In the present study, we tested the hypothesis that D. reticulatus possesses an efficient breeding strategy that allows for a rapid increase in tick numbers and densities through the formation of mixed-sex clusters/aggregations while questing in the environment. METHODS An observational study was carried out in the spring of 2023, at three sites in two regions in Central and North-Eastern Poland, both characterised by high tick densities. At each site, a 400-m-long transect was inspected for questing ticks. All noted ticks were collected, and tick numbers and sexes per stem were recorded. Differences in tick distribution by site and sex were analysed statistically. RESULTS A total of 371 D. reticulatus (219 females, 152 males) ticks were collected from 270 grass stems over a combined 1200 m of transect. The majority of grass stems (74.4%) were occupied by just a single individual, with two-tick clusters the second most common category. The maximum number of D. reticulatus individuals observed on a single grass stem was six. Mixed-sex clusters were significantly more common than single-sex clusters at all three sites. With study sites combined, mixed-sex clusters accounted for 17.4% (95% confidence limit [95% CL] 13.9-21.6%) of observations, while for multiple males and multiple females, the values were 2.6% (95% CL: 1.4-4.7%) and 5.6% (95% CL: 3.7-8.3%), respectively. CONCLUSIONS Mixed-sex clusters of D. reticulatus ticks were significantly more common than single-sex clusters, which we hypothesise reflects an efficient, likely pheromone-mediated breeding strategy of this expansive tick species.
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Affiliation(s)
- Dagmara Wężyk
- Department of Eco-Epidemiology of Parasitic Diseases, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Wiktoria Romanek
- Department of Eco-Epidemiology of Parasitic Diseases, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Wiktoria Małaszewicz
- Department of Eco-Epidemiology of Parasitic Diseases, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Jerzy M Behnke
- School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Anna Bajer
- Department of Eco-Epidemiology of Parasitic Diseases, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland.
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3
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Chalchisa A, Kumsa B, Gutema Wegi F. Biting Flies and Associated Pathogens in Camels in Amibara District of Afar Region, Ethiopia. Vet Med Int 2024; 2024:5407898. [PMID: 38234317 PMCID: PMC10791415 DOI: 10.1155/2024/5407898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 12/25/2023] [Accepted: 12/28/2023] [Indexed: 01/19/2024] Open
Abstract
Biting flies and associated pathogens are the major health constraints on camel production and productivity and are implicated in causing significant economic losses in the pastoralist community in Ethiopia. A cross-sectional study was conducted to estimate the prevalence of biting flies and their associated pathogens in relation to different risk factors in camels in the Amibara district, from October 2019 to April 2020. A total of 480 camels were examined for biting flies and associated pathogens. The study revealed that overall, 87% (418/480) and 18% (87/480) of camels were infested by one or more biting flies and infected with Trypanosoma evansi during the study period, respectively. The collected biting flies were identified into a total of 3 genera: Hippobosca, Stomoxys, and Tabanus under the stereomicroscope. In the present study, Hippobosca (40.4%) was the most prevalent biting fly, followed by Stomoxys (31%) and Tabanus (28.6%), which affected camels in the study area. Among camels infected with Trypanosoma evansi, 7.3% and 16% were positive for parasitological and serological tests, respectively. Age, body condition score, and season appeared to have a significant effect (p ≤ 0.005) on the prevalence of biting flies and T. evansi on dromedaries. According to the findings of this study, biting flies and Trypanosoma evansi were the most common limitations on camel health, production, and productivity in the study area. As a result of the possible threat of biting flies' infestation and Trypanosoma evansi on camels, all-around attention is required in terms of strategic acaricide application, proper antiprotozoal drug use, and raising knowledge about acaricide use to prevent and control biting flies' infestation.
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Affiliation(s)
- Adugna Chalchisa
- College of Veterinary Medicine, Haramaya University, P.O. Box 138, Dire Dawa, Ethiopia
| | - Bersissa Kumsa
- College of Veterinary Medicine and Agriculture, AAU, Addis Ababa University, P.O. Box 1174, Addis Ababa, Ethiopia
| | - Fekadu Gutema Wegi
- Ethiopian Institute of Agricultural Research, Holeta Agricultural Research Center, Holeta, Ethiopia
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4
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Siegel EL, Xu G, Li AY, Pearson P, D’hers S, Elman N, Mather TN, Rich SM. Ixodes scapularis Is the Most Susceptible of the Three Canonical Human-Biting Tick Species of North America to Repellent and Acaricidal Effects of the Natural Sesquiterpene, (+)-Nootkatone. INSECTS 2023; 15:8. [PMID: 38249014 PMCID: PMC10816182 DOI: 10.3390/insects15010008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 01/23/2024]
Abstract
Ticks are vectors of many human and animal zoonotic disease-causing agents causing significant global health and economic strain. Repellents and acaricides are integral to the human capacity for personal protection from tick bites. Nootkatone, a naturally occurring sesquiterpene found in the Alaskan cedar tree, grapefruit, and other sources, has been documented to be a potent acaricide. Research has also noted repellent effects against some tick species. In this study, our aim was to investigate the effect of synthetic, high-purity (+)-nootkatone on adult Ixodes scapularis, Dermacentor variabilis, and Amblyomma americanum ticks in an in vitro, vertical filter paper bioassay. (+)-nootkatone showed compelling tick repellency, but median effective concentrations (EC50) significantly differed among species. Ixodes scapularis were repelled at very low concentrations (EC50 = 0.87 ± 0.05 µg/cm2). Higher concentrations were required to repel D. variabilis (EC50 = 252 ± 12 µg/cm2) and A. americanum (EC50 = 2313 ± 179 µg/cm2). Significant post-exposure mortality, assessed 24 h after repellency trials, was also observed in I. scapularis but was absent entirely in D. variabilis and A. americanum. These tests demonstrate that nootkatone has a promising dual-action personal protection capacity against adult I. scapularis ticks, warranting further investigation in more natural environments and in the presence of host cues.
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Affiliation(s)
- Eric L. Siegel
- Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA; (E.L.S.); (P.P.)
| | - Guang Xu
- Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA; (E.L.S.); (P.P.)
| | - Andrew Y. Li
- United States Department of Agriculture, Agricultural Research Service, Invasive Insect Biocontrol and Behavior Laboratory, Beltsville, MD 20704, USA;
| | - Patrick Pearson
- Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA; (E.L.S.); (P.P.)
| | - Sebastián D’hers
- Computational Mechanics Center, Instituto Tecnológico de Buenos Aires (ITBA), Ciudad Autónoma de Buenos Aires C1106ACD, Argentina;
| | - Noel Elman
- GearJump Technologies, Limited Liability Company, Brookline, MA 02446, USA;
| | - Thomas N. Mather
- Center for Vector-Borne Disease, University of Rhode Island, Kingston, RI 02881, USA;
| | - Stephen M. Rich
- Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA; (E.L.S.); (P.P.)
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Valcárcel F, Elhachimi L, Vilá M, Tomassone L, Sánchez M, Selles SMA, Kouidri M, González MG, Martín-Hernández R, Valcárcel Á, Fernández N, Tercero JM, Sanchis J, Bellido-Blasco J, González-Coloma A, Olmeda AS. Emerging Hyalomma lusitanicum: From identification to vectorial role and integrated control. MEDICAL AND VETERINARY ENTOMOLOGY 2023; 37:425-459. [PMID: 37144688 DOI: 10.1111/mve.12660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 04/11/2023] [Indexed: 05/06/2023]
Abstract
In the Mediterranean basin, the tick species Hyalomma lusitanicum Koch stands out among other species of the Hyalomma genus due to its wide distribution, and there is great concern about its potential role as a vector and/or reservoir and its continuous expansion to new areas because of climate warming and human and other animal movements. This review aims to consolidate all the information on H. lusitanicum, including taxonomy and evolution, morphological and molecular identification, life cycle, sampling methods, rearing under laboratory conditions, ecology, hosts, geographical distribution, seasonality, vector role and control methods. The availability of adequate data is extremely relevant to the development of appropriate control strategies in areas where this tick is currently distributed as well as in new areas where it could become established in the near future.
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Affiliation(s)
- Félix Valcárcel
- Grupo de Parasitología Animal, Departamento de Reproducción Animal, INIA-CSIC, Madrid, Spain
| | - L Elhachimi
- Département de parasitologie et de Santé Publique, Institut Agronomique et Vétérinaire Hassan II, Rabat, Morocco
| | - M Vilá
- Grupo de Investigación COPAR (GI-2120; USC), Departamento de Patoloxia Animal, Facultade de Veterinaria, Universidade de Santiago de Compostela, Lugo, Spain
| | - L Tomassone
- Department of Veterinary Sciences, University of Turin, Turin, Italy
| | - M Sánchez
- Grupo de Parasitología Animal, Departamento de Reproducción Animal, INIA-CSIC, Madrid, Spain
- Villamagna S.A., Finca "La Garganta", Villanueva de Córdoba, Spain
- Facultad de Veterinaria, Universidad Alfonso X El Sabio (UAX), Madrid, Spain
| | - S M A Selles
- Institute of Veterinary Sciences, University of Tiaret, Tiaret, Algeria
- Laboratory of Research on Local Animal Products, University of Tiaret, Tiaret, Algeria
| | - M Kouidri
- Laboratory of Farm Animal Products, University of Tiaret, Tiaret, Algeria
| | - M G González
- Grupo de Parasitología Animal, Departamento de Reproducción Animal, INIA-CSIC, Madrid, Spain
- Villamagna S.A., Finca "La Garganta", Villanueva de Córdoba, Spain
| | - R Martín-Hernández
- Laboratorio de Patología Apícola, Centro de Investigación Apícola y Agroambiental (CIAPA), IRIAF-Instituto Regional de Investigación y Desarrollo Agroalimentario y Forestal, Marchamalo, 19180, Spain. Instituto de Recursos Humanos para la Ciencia y la Tecnología (INCRECYT-ESF/EC-FSE), Fundación Parque Científico y Tecnológico de Castilla-La Mancha, Albacete, Spain
| | - Á Valcárcel
- Lokimica S.L., c/ Valdemorillo, Madrid, Spain
- Veterinary Pathobiology section, University College Dublín, Dublin 4, Ireland
| | - N Fernández
- Facultad de Veterinaria, Universidad Alfonso X El Sabio (UAX), Madrid, Spain
| | - J M Tercero
- Villamagna S.A., Finca "La Garganta", Villanueva de Córdoba, Spain
| | - J Sanchis
- Facultad de Veterinaria, CENUR Litoral Norte, Universidad de la República, Uruguay
| | - J Bellido-Blasco
- Sección de Epidemiología, Centro de Salud Pública de Castelló, CIBER-ESP. Universitat Jaume I (UJI), Castelló, Spain
| | | | - A S Olmeda
- Departamento de Sanidad Animal, Facultad de Veterinaria, UCM, Madrid, Spain
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Tardy O, Acheson ES, Bouchard C, Chamberland É, Fortin A, Ogden NH, Leighton PA. Mechanistic movement models to predict geographic range expansions of ticks and tick-borne pathogens: Case studies with Ixodes scapularis and Amblyomma americanum in eastern North America. Ticks Tick Borne Dis 2023; 14:102161. [PMID: 36996508 DOI: 10.1016/j.ttbdis.2023.102161] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/30/2023]
Abstract
The geographic range of the blacklegged tick, Ixodes scapularis, is expanding northward from the United States into southern Canada, and studies suggest that the lone star tick, Amblyomma americanum, will follow suit. These tick species are vectors for many zoonotic pathogens, and their northward range expansion presents a serious threat to public health. Climate change (particularly increasing temperature) has been identified as an important driver permitting northward range expansion of blacklegged ticks, but the impacts of host movement, which is essential to tick dispersal into new climatically suitable regions, have received limited investigation. Here, a mechanistic movement model was applied to landscapes of eastern North America to explore 1) relationships between multiple ecological drivers and the speed of the northward invasion of blacklegged ticks infected with the causative agent of Lyme disease, Borrelia burgdorferi sensu stricto, and 2) its capacity to simulate the northward range expansion of infected blacklegged ticks and uninfected lone star ticks under theoretical scenarios of increasing temperature. Our results suggest that the attraction of migratory birds (long-distance tick dispersal hosts) to resource-rich areas during their spring migration and the mate-finding Allee effect in tick population dynamics are key drivers for the spread of infected blacklegged ticks. The modeled increases in temperature extended the climatically suitable areas of Canada for infected blacklegged ticks and uninfected lone star ticks towards higher latitudes by up to 31% and 1%, respectively, and with an average predicted speed of the range expansion reaching 61 km/year and 23 km/year, respectively. Differences in the projected spatial distribution patterns of these tick species were due to differences in climate envelopes of tick populations, as well as the availability and attractiveness of suitable habitats for migratory birds. Our results indicate that the northward invasion process of lone star ticks is primarily driven by local dispersal of resident terrestrial hosts, whereas that of blacklegged ticks is governed by long-distance migratory bird dispersal. The results also suggest that mechanistic movement models provide a powerful approach for predicting tick-borne disease risk patterns under complex scenarios of climate, socioeconomic and land use/land cover changes.
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7
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Bilgiç HB, Hacilarlioğlu S, Pekağirbaş M, Karagenç T, Eren H, Bakirci S. In vitro feeding of Hyalomma excavatum and Hyalomma marginatum tick species. Parasitol Res 2023:10.1007/s00436-023-07867-7. [PMID: 37178257 DOI: 10.1007/s00436-023-07867-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 05/08/2023] [Indexed: 05/15/2023]
Abstract
The rearing of ticks is an important technique for studies aiming to elucidate the course and pathogenesis of tick-borne diseases (TBDs). TBDs caused by protozoans (Theileria, Babesia) and bacteria (Anaplasma/Ehrlichia) impose a serious constraint upon livestock health and production in tropical and sub-tropical regions where the distributions of host, pathogen, and vector overlap. This study focuses on Hyalomma marginatum, one of the most important Hyalomma species in the Mediterranean region, being a vector of the virus that causes Crimean-Congo haemorrhagic fever in humans, together with H. excavatum, a vector of Theileria annulata, an important protozoan of cattle. The adaptation of ticks to feeding on artificial membranes allows the creation of model systems that can be put to use examining the underlying mechanisms of pathogen transmission by ticks. Silicone membranes, in particular, offer researchers the flexibility to adjust membrane thickness and content during artificial feeding. The aim of the present study was to develop an artificial feeding technique using silicone-based membranes for all developmental stages of H. excavatum and H. marginatum ticks. Attachment rates after feeding on silicone membranes for females H. marginatum and H. excavatum were 8.33% (8/96) and 7.95% (7/88), respectively. The use of cow hair as a stimulant increased the attachment rate of H. marginatum adults in comparison to other stimulants. The engorgement of H. marginatum and H. excavatum females took 20.5 and 23 days with average weights of 307.85 and 260.64 mg, respectively. Although both tick species could complete egg-laying, and this was followed by hatching of larvae; their larvae and nymphs could not be fed artificially. Taken together, the results of the present study clearly indicate that silicone membranes are suitable for feeding of H. excavatum and H. marginatum adult ticks, supporting engorgement, laying of eggs, and hatching of the larvae. They thus represent a versatile tool for studying transmission mechanisms of tick-borne pathogens. Further studies are warranted to examine attachment and feeding behaviours in order to increase the success of artificial feeding of larvae and nymphal stages.
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Affiliation(s)
- Hüseyin Bilgin Bilgiç
- Faculty of Veterinary Medicine, Department of Parasitology, Aydın Adnan Menderes University, Isıklı-Efeler, Aydın, Türkiye
| | - Selin Hacilarlioğlu
- Faculty of Veterinary Medicine, Department of Parasitology, Aydın Adnan Menderes University, Isıklı-Efeler, Aydın, Türkiye
| | - Metin Pekağirbaş
- Faculty of Veterinary Medicine, Department of Parasitology, Aydın Adnan Menderes University, Isıklı-Efeler, Aydın, Türkiye
| | - Tülin Karagenç
- Faculty of Veterinary Medicine, Department of Parasitology, Aydın Adnan Menderes University, Isıklı-Efeler, Aydın, Türkiye
| | - Hasan Eren
- Faculty of Veterinary Medicine, Department of Parasitology, Aydın Adnan Menderes University, Isıklı-Efeler, Aydın, Türkiye
| | - Serkan Bakirci
- Faculty of Veterinary Medicine, Department of Parasitology, Aydın Adnan Menderes University, Isıklı-Efeler, Aydın, Türkiye.
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First description of conspecific hyperparasitism in Amblyomma sculptum. Ticks Tick Borne Dis 2023; 14:102092. [PMID: 36516615 DOI: 10.1016/j.ttbdis.2022.102092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 12/12/2022]
Abstract
The present study reports a case of conspecific hyperparasitism for Amblyomma sculptum. Two partially engorged females were collected from two naturally infested dairy cows and placed in a single petri dish to be transported to the laboratory, where they were held in a biological oxygen demand (BOD) incubator chamber under controlled conditions of 27 ± 1 °C and 85 ± 5% RH. After one day, it was observed that the smaller female (female 1) was attached to the dorsal surface of the larger female (female 2). The hypostome and chelicerae of the female 1 were entirely inserted into the cuticle of the female 2, characterizing tick attachment. Pictures were taken to illustrate the finding. After a few hours, the female 1 detached spontaneously and showed no visible signs of additional enlargement (engorgement). The females did not lay eggs and the survival period was not recorded. To our knowledge this is the first report of hyperparasitism for A. sculptum and the fourth for the genus Amblyomma.
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Fracasso G, Heylen D, Matthysen E. Male mating preference in an ixodid tick. Parasit Vectors 2022; 15:316. [PMID: 36071436 PMCID: PMC9450281 DOI: 10.1186/s13071-022-05419-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 07/27/2022] [Indexed: 11/15/2022] Open
Abstract
Background Mate choice is a fundamental element of sexual selection and has the potential to shape the evolution of traits. Mate choice based on body size has been shown to be a common trait in several arthropod species. In hard ticks, a taxon of medical and veterinary importance, engorgement weight is positively correlated with reproductive output but it is unknown whether adult males show mate choice. Here, we experimentally investigated whether males (i) use chemical cues to choose their mating partner, (ii) consistently choose for the same female individual and (iii) prefer females with highest weight after feeding. Methods We used two experimental setups which allowed chemical communication between ticks: (i) a horizontal tube preventing physical contact with the female and (ii) an arena where tactile cues were allowed. In total, we tested 62 different triads in 124 tests (66 tests in the horizontal tube and 58 in the arena) composed of one male that could choose between two engorged females. Specifically, we tested 42 triads in the tube and 46 in the arena; 24 triads were repeatedly tested in the tube while 38 triads were tested in both setups. Results We found no preference for individual or heavier females in either setup. However, in the horizontal tube setup, males significantly preferred females that were not visited by them in the previous test. Conclusions Our results suggest a lack of male mate choice despite heavier females having higher fecundity. However, future studies should take into account that males may recognize the potential mating partners they previously met. Graphical Abstract ![]()
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Affiliation(s)
- Gerardo Fracasso
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, 2610, Wilrijk, Belgium. .,Eco-Epidemiology Group, Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium.
| | - Dieter Heylen
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, 2610, Wilrijk, Belgium.,Eco-Epidemiology Group, Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium.,Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, 3590, Diepenbeek, Belgium
| | - Erik Matthysen
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, 2610, Wilrijk, Belgium
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Bensaoud C, Tenzer S, Poplawski A, Medina JM, Jmel MA, Voet H, Mekki I, Aparicio-Puerta E, Cuveele B, Distler U, Marini F, Hackenberg M, Kotsyfakis M. Quantitative proteomics analysis reveals core and variable tick salivary proteins at the tick-vertebrate host interface. Mol Ecol 2022; 31:4162-4175. [PMID: 35661311 DOI: 10.1111/mec.16561] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 03/30/2022] [Accepted: 04/04/2022] [Indexed: 11/28/2022]
Abstract
Few studies have examined tick proteomes, how they adapt to their environment, and their roles in the parasite-host interactions that drive tick infestation and pathogen transmission. Here we used a proteomics approach to screen for biologically and immunologically relevant proteins acting at the tick-host interface during tick feeding and, as proof of principle, measured host antibody responses to some of the discovered candidates. We used a label-free quantitative proteomic workflow to study salivary proteomes of (i) wild Ixodes ricinus ticks fed on different hosts; (ii) wild or laboratory ticks fed on the same host; and (iii) adult ticks co-fed with nymphs. Our results reveal high and stable expression of several protease inhibitors and other tick-specific proteins under different feeding conditions. Most pathways functionally enriched in sialoproteomes were related to proteolysis, endopeptidase, and amine-binding activities. The generated catalog of tick salivary proteins enabled the selection of six candidate secreted immunogenic peptides for rabbit immunizations, three of which induced strong and durable antigen-specific antibody responses in rabbits. Furthermore, rabbits exposed to ticks mounted immune responses against the candidate peptides/proteins, confirming their expression at the tick-vertebrate interface. Our approach provides insights into tick adaptation strategies to different feeding conditions and promising candidates for developing anti-tick vaccines or markers of exposure of vertebrate hosts to tick bites.
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Affiliation(s)
- Chaima Bensaoud
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Budweis, Czechia
| | - Stefan Tenzer
- Institute for Immunology, University Medical Center of the Johannes-Gutenberg University Mainz, Mainz, Germany
| | - Alicia Poplawski
- Institute of Medical Biostatistics, Epidemiology and Informatics, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - José María Medina
- Dpto. de Genética, Facultad de Ciencias, Universidad de Granada, Campus de Fuentenueva s/n, Granada, Spain.,Lab. de Bioinformática, Centro de Investigación Biomédica, PTS, Instituto de Biotecnología, Avda. del Conocimiento s/n, Granada, Spain
| | - Mohamed Amine Jmel
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Budweis, Czechia
| | - Hanne Voet
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Budweis, Czechia.,University of Antwerp, Wilrijk, Belgium
| | - Imen Mekki
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Budweis, Czechia.,Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic
| | - Ernesto Aparicio-Puerta
- Dpto. de Genética, Facultad de Ciencias, Universidad de Granada, Campus de Fuentenueva s/n, Granada, Spain.,Lab. de Bioinformática, Centro de Investigación Biomédica, PTS, Instituto de Biotecnología, Avda. del Conocimiento s/n, Granada, Spain
| | - Brent Cuveele
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Budweis, Czechia.,University of Antwerp, Wilrijk, Belgium
| | - Ute Distler
- Institute for Immunology, University Medical Center of the Johannes-Gutenberg University Mainz, Mainz, Germany
| | - Federico Marini
- Institute of Medical Biostatistics, Epidemiology and Informatics, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Michael Hackenberg
- Dpto. de Genética, Facultad de Ciencias, Universidad de Granada, Campus de Fuentenueva s/n, Granada, Spain.,Lab. de Bioinformática, Centro de Investigación Biomédica, PTS, Instituto de Biotecnología, Avda. del Conocimiento s/n, Granada, Spain
| | - Michalis Kotsyfakis
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Budweis, Czechia
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11
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The current strategies and underlying mechanisms in the control of the vector tick, Haemaphysalis longicornis: Implications for future integrated management. Ticks Tick Borne Dis 2022; 13:101905. [DOI: 10.1016/j.ttbdis.2022.101905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 01/09/2022] [Accepted: 01/10/2022] [Indexed: 11/17/2022]
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12
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Manoj RRS, Latrofa MS, Bezerra-Santos MA, Sgroi G, Samarelli R, Mendoza-Roldan JA, Otranto D. Molecular detection and characterization of the endosymbiont Wolbachia in the European hedgehog flea, Archaeopsylla erinacei. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2022; 97:105161. [PMID: 34843992 DOI: 10.1016/j.meegid.2021.105161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 11/19/2021] [Accepted: 11/24/2021] [Indexed: 06/13/2023]
Abstract
Wolbachia, the endosymbiont of arthropods and onchocercid nematodes is present in many medically important insect species, being also considered for the indirect control of parasitic ones. Archaeopsylla erinacei is a flea species infesting hedgehogs acting as vector of Rickettsia felis, Bartonella henselae, and Rickettsia helvetica, thus having public health relevance. The Wolbachia surface protein (wsp) and 16S rRNA genes were used to determine the presence, prevalence and molecular typing of Wolbachia in this flea species collected in two regions of southern Italy. Of the 45 fleas tested (n = 16 males, 35.6%; n = 29 females, 64.4%), 43 (95.6%; 95% CI: 84.8-99.2) scored positive for Wolbachia, of which 15 (33.3%) and 28 (62.2%) were males and females, respectively. The sex-wise prevalence of this endosymbiont was almost equal in both sexes (males 93.8%; 95% CI: 69.5-99.7; females 96.7%; 95% CI: 83.1-99.8). Single locus sequence analysis (SLST) of Wolbachia revealed two sequence types for 16S rRNA gene, named as wAr_15227 and wAr_15234, which came from two different areas, equally distributed in male and female fleas, whilst only one sequence type was identified for wsp gene. The phylogenetic analysis placed the two 16S rRNA sequence types in paraphyletic clades belonging to the supergroup A and B, respectively. Whilst, the tree of wsp gene clustered the corresponding sequence in the same clade including those of Wolbachia supergroup A. In MLST analyses, both Wolbachia sequence types clustered in a monophyletic clade with Drosophila nikananu (wNik) and Drosophila sturtevanti (wStv) from supergroup A. ClonalFrame analysis revealed a recombination event in the wAr_15234 strain which came from Apulia region. Scientific knowledge of the presence/prevalence of Wolbachia among medically important fleas, may contribute to develop an alternative biological method for the vector control.
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Affiliation(s)
| | | | | | - Giovanni Sgroi
- Department of Veterinary Medicine, University of Bari, Valenzano, Italy
| | | | | | - Domenico Otranto
- Department of Veterinary Medicine, University of Bari, Valenzano, Italy; Faculty of Veterinary Sciences, Bu-Ali Sina University, Hamedan, Iran.
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13
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Selles SMA, Kouidri M, González MG, González J, Sánchez M, González-Coloma A, Sanchis J, Elhachimi L, Olmeda AS, Tercero JM, Valcárcel F. Acaricidal and Repellent Effects of Essential Oils against Ticks: A Review. Pathogens 2021; 10:pathogens10111379. [PMID: 34832535 PMCID: PMC8617816 DOI: 10.3390/pathogens10111379] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/11/2021] [Accepted: 10/15/2021] [Indexed: 11/30/2022] Open
Abstract
Tick control is a priority in order to prevent the transmission of vector-borne diseases. Industrial chemical acaricides and repellents have been the most efficient tools against hard ticks for a long time. However, the appearance of resistances has meant the declining effectiveness of the chemicals available on the market. The trend today is to develop alternative control methods using natural products to replace nonefficient pesticides and to preserve the efficient ones, hoping to delay resistance development. Traditional in vitro evaluation of acaricidal activity or resistance to synthetic pesticides have been reviewed and they mainly focus on just one species, the one host tick (Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)). Recent reports have called for the standardization of natural product components, extraction techniques, and experimental design to fully discover their acaricidal potential. This study reviews the main variables used in the bibliography about the efficiency of natural products against ticks, and it proposes a unification of variables relating to ticks, practical development of bioassays, and estimation of ixodicidal activity.
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Affiliation(s)
- Sidi Mohammed Ammar Selles
- Institute of Veterinary Sciences, University of Tiaret, Tiaret 14000, Algeria;
- Laboratory of Research on Local Animal Products, University of Tiaret, Tiaret 14000, Algeria
- Correspondence:
| | - Mokhtaria Kouidri
- Institute of Veterinary Sciences, University of Tiaret, Tiaret 14000, Algeria;
- Laboratory of Farm Animal Products, University of Tiaret, Tiaret 14000, Algeria
| | - Marta G. González
- Grupo de Parasitología Animal, Departamento de Reproducción Animal (INIA-CSIC), 28040 Madrid, Spain; (M.G.G.); (M.S.); (J.S.); (F.V.)
| | - Julia González
- Center for Vector Biology, Department of Entomology, Rutgers University, New Brunswick, NJ 08901, USA;
| | - María Sánchez
- Grupo de Parasitología Animal, Departamento de Reproducción Animal (INIA-CSIC), 28040 Madrid, Spain; (M.G.G.); (M.S.); (J.S.); (F.V.)
- Villamagna S.A., Finca “La Garganta”, 14440 Villanueva de Córdoba, Spain;
| | - Azucena González-Coloma
- Instituto de Ciencias Agrarias (ICA), Consejo Superior de Investigaciones Científicas (CSIC), 28006 Madrid, Spain;
| | - Jaime Sanchis
- Grupo de Parasitología Animal, Departamento de Reproducción Animal (INIA-CSIC), 28040 Madrid, Spain; (M.G.G.); (M.S.); (J.S.); (F.V.)
- Facultad de Veterinaria, CENUR Litoral Norte, Universidad de la República, Rivera, Salto 1350, Uruguay
| | - Latifa Elhachimi
- Département de parasitologie et de Santé Publique, Institut Agronomique et Vétérinaire Hassan II, Rabat B.P. 6202, Morocco;
| | - A. Sonia Olmeda
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain;
| | - José Maria Tercero
- Villamagna S.A., Finca “La Garganta”, 14440 Villanueva de Córdoba, Spain;
| | - Félix Valcárcel
- Grupo de Parasitología Animal, Departamento de Reproducción Animal (INIA-CSIC), 28040 Madrid, Spain; (M.G.G.); (M.S.); (J.S.); (F.V.)
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14
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Koloski CW, Cassone BJ. Transcriptional profiling of Dermacentor variabilis (Acari: Ixodidae) provides insights into the role of the Haller's organ in spatial DEET recognition. Ticks Tick Borne Dis 2021; 13:101827. [PMID: 34610525 DOI: 10.1016/j.ttbdis.2021.101827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 11/30/2022]
Abstract
DEET is the most common active ingredient in commercial repellents, providing effective protection against blood-sucking insects and ticks. However, its mode of action is not fully understood, with several theories put forward to explain its repellency effect. Unique to ticks, the Haller's organ recognizes a variety of external stimuli through non-contact mechanisms, yet the extent to which the organ plays a role in tick chemoreception is not fully known. We previously found that DEET inhibited the expression/activity of cytochrome P450s and cholinesterases in Dermacentor variabilis, however, our experimental design could not distinguish between sexes (males/females), method of exposure (volatile/tactile) or the roles of chemosensory tissues (Haller's organ). In this study, we used RNA sequencing to assess changes in transcript expression induced by volatile DEET in D. variabilis males/females with/without intact Haller's organs. Male ticks showed much greater transcriptional responses to DEET than females, which may be at least partially attributed to the sexual dimorphism of the Haller's organ. Female transcript expression profiles were most influenced by condition (i.e., intact/excised Haller's organs) with minimal changes due to repellent exposure. On the other hand, removal of the Haller's organs caused DEET treated male ticks to exhibit similar expression profiles as control (ethanol) ticks with intact Haller's organs. Consequently, the transcript-level responses to spatial DEET exposure appears largely based on males possessing their Haller's organs. The molecular signature of this response included the suppression of a large number of transcripts involved in detoxification, lipid metabolism and immunity. Taken collectively, this study furthers our understanding of the Haller's organ role in volatile DEET recognition.
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Affiliation(s)
- Cody W Koloski
- Department of Biology, Brandon University, Brandon, MB R78 6A9, Canada
| | - Bryan J Cassone
- Department of Biology, Brandon University, Brandon, MB R78 6A9, Canada.
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15
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Pereira DFS, Ribeiro HS, Gonçalves AAM, da Silva AV, Lair DF, de Oliveira DS, Boas DFV, Conrado IDSS, Leite JC, Barata LM, Reis PCC, Mariano RMDS, Santos TAP, Coutinho DCO, Gontijo NDF, Araujo RN, Galdino AS, Paes PRDO, Melo MM, Nagem RAP, Dutra WO, Silveira-Lemos DD, Rodrigues DS, Giunchetti RC. Rhipicephalus microplus: An overview of vaccine antigens against the cattle tick. Ticks Tick Borne Dis 2021; 13:101828. [PMID: 34628330 DOI: 10.1016/j.ttbdis.2021.101828] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 01/08/2023]
Abstract
Rhipicephalus microplus, popularly known as the cattle tick, is the most important tick of livestock as it is responsible for significant economic losses. The use of chemical acaricides is still the most widely used control method despite its known disadvantages. Vaccination would be a safe alternative for the control of R. microplus and holds advantages over the use of chemical acaricides as it is environmental-friendly and leaves no residues in meat or milk. Two vaccines based on the Bm86 protein were commercialized, TickGARD® and Gavac®, with varying reported efficacies in different countries. The use of other vaccines, such as Tick Vac®, Go-Tick®, and Bovimune Ixovac® have been restricted to some countries. Several other proteins have been analyzed as possible antigens for more effective vaccines against R. microplus, including peptidases, serine proteinase inhibitors, glutathione S-transferases, metalloproteases, and ribosomal proteins, with efficacies ranging from 14% to 96%. Nonetheless, more research is needed to develop safe and efficient tick vaccines, such as the evaluation of the efficacy of antigens against other tick species to verify cross-reactivity and inclusion of additional antigens to promote the blocking of the infection and spreading of tick-borne diseases. This review summarizes the discoveries of candidate antigens for R. microplus tick vaccines as well as the methods used to test their efficacy.
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Affiliation(s)
- Diogo Fonseca Soares Pereira
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Helen Silva Ribeiro
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Ana Alice Maia Gonçalves
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Augusto Ventura da Silva
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Daniel Ferreira Lair
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Diana Souza de Oliveira
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Diego Fernandes Vilas Boas
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Ingrid Dos Santos Soares Conrado
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Jaqueline Costa Leite
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Luccas Miranda Barata
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Pedro Campos Carvalhaes Reis
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Reysla Maria da Silveira Mariano
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Thaiza Aline Pereira Santos
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Danielle Carvalho Oliveira Coutinho
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | - Nelder de Figueiredo Gontijo
- Laboratory of Physiology of Hematophagous Insects, Department of Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ricardo Nascimento Araujo
- Laboratory of Physiology of Hematophagous Insects, Department of Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Alexsandro Sobreira Galdino
- Microbial Biotechnology Laboratory, Biochemistry, Federal University of São João Del-Rei, Divinópolis, Minas Gerais, Brazil
| | - Paulo Ricardo de Oliveira Paes
- Department of Veterinary Clinical Medicine and Surgery, College of Veterinary Medicine, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Marília Martins Melo
- Department of Veterinary Clinical Medicine and Surgery, College of Veterinary Medicine, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ronaldo Alves Pinto Nagem
- Structural Biology and Biotechnology Laboratory, Department of biochemistry and immunology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Walderez Ornelas Dutra
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil
| | | | | | - Rodolfo Cordeiro Giunchetti
- Laboratory of Cell-Cell Interactions, Institute of Biological Sciences, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, 31270-901, Minas Gerais, Brazil.
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16
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Seasonal distribution of Haemaphysalis longicornis (Acari: Ixodidae) and detection of SFTS virus in Gyeongbuk Province, Republic of Korea, 2018. Acta Trop 2021; 221:106012. [PMID: 34126090 DOI: 10.1016/j.actatropica.2021.106012] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 05/15/2021] [Accepted: 06/04/2021] [Indexed: 11/21/2022]
Abstract
The seasonal distribution of hard ticks was investigated in 2018 in Gyeongbuk Province, Republic of Korea. Ticks were assayed for severe fever with thrombocytopenia syndrome virus (SFTSV). Ticks were collected monthly using CO2-baited traps from April to November in four habitats (grasslands, grave sites, hiking trails, and mixed forests). Based on morphological and molecular identification, Haemaphysalis longicornis was the most commonly collected species, followed by H. flava and Ixodes nipponensis. Ticks were more commonly collected in grassland habitats, followed by the grave sites, hiking trails, and mixed forests. Peak numbers of nymphs and adults of H. longicornis occurred in May and June, respectively, and Haemaphysalis larvae were collected from August to October. A total of 9/187 (4.8%) pools were positive for SFTSV between June and October in 2018. Phylogenetic analysis of partial fragments of the SFTSV obtained in this study showed that all positive virus samples clustered into genotype B.
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17
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S G, Ravi Latha B, C S, V L. Solar tick trap with a pheromone lure - A stand-in approach for off-host control of Rhipicephalus sanguineus sensu lato ticks. Ticks Tick Borne Dis 2021; 12:101656. [PMID: 33529987 DOI: 10.1016/j.ttbdis.2021.101656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 01/04/2021] [Accepted: 01/08/2021] [Indexed: 11/28/2022]
Abstract
Rhipicephalus sanguineus sensu lato (s.l.), the brown dog tick, transmits several important haemo-protozoan and rickettsial pathogens to dogs. Effective control of these ticks is entirely by the use of acaricidal preparations both on and off the host. Indiscriminate use of acaricides can cause environmental pollution and toxicity to humans as well as development of acaricidal resistance in ticks. As an alternative control strategy, a novel, eco-friendly and economical solar tick trap, which attracts ticks using pheromones and kills them by electrocution, was fabricated for use in kennels to control different stages of ticks. All stages of ticks were found to be lured to sex pheromone (SP), assembly pheromone (AP) and a combination of SP + AP impregnated vapour patches and electrocuted. There was a highly significant (p < 0.01) difference in the level of attraction between engorged and questing stages of ticks to the pheromones in the trap. AP lured a higher number of ticks, both engorged and questing, in comparison to other pheromones. The solar tick trap bearing vapour patch impregnated with AP was considered most suitable for use in integrated pest management (IPM) of ticks in heavily infested kennels. The solar trap remained effective for a month after which, replacement of pheromone impregnated vapour patch was necessary for continued and effective attraction of the ticks. This solar tick trap device, which uses pheromone without any acaricide, could prove to be an ideal green alternative for use in IPM of ticks in kennels.
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Affiliation(s)
- Gowrishankar S
- Department of Veterinary Parasitology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600 007, India.
| | - Bhaskaran Ravi Latha
- Department of Veterinary Parasitology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600 007, India
| | - Sreekumar C
- Department of Wildlife Science, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600 007, India
| | - Leela V
- Department of Veterinary Physiology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600 007, India
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18
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Vaccine approaches applied to controlling dog ticks. Ticks Tick Borne Dis 2021; 12:101631. [PMID: 33494026 DOI: 10.1016/j.ttbdis.2020.101631] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/17/2020] [Accepted: 11/18/2020] [Indexed: 11/20/2022]
Abstract
Ticks are considered the most important vectors in veterinary medicine with a profound impact on animal health worldwide, as well as being key vectors of diseases affecting household pets. The leading strategy applied to dog tick control is the continued use of acaricides. However, this approach is not sustainable due to surging tick resistance, growing public concern over pesticide residues in food and in the environment, and the rising costs associated with their development. In contrast, tick vaccines are a cost-effective and environmentally friendly alternative against tick-borne diseases by controlling vector infestations and reducing pathogen transmission. These premises have encouraged researchers to develop an effective vaccine against ticks, with several proteins having been characterized and used in native, synthetic, and recombinant forms as antigens in immunizations. The growing interaction between domestic pets and people underscores the importance of developing new tick control measures that require effective screening platforms applied to vaccine development. However, as reviewed in this paper, very little progress has been made in controlling ectoparasite infestations in pets using the vaccine approach. The control of tick infestations and pathogen transmission could be obtained through immunization programs aimed at reducing the tick population and interfering in the pathogenic transmission that affects human and animal health on a global scale.
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19
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Josek T, Sperrazza J, Alleyne M, Syed Z. Neurophysiological and behavioral responses of blacklegged ticks to host odors. JOURNAL OF INSECT PHYSIOLOGY 2021; 128:104175. [PMID: 33253713 DOI: 10.1016/j.jinsphys.2020.104175] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 11/10/2020] [Accepted: 11/25/2020] [Indexed: 06/12/2023]
Abstract
The blacklegged tick, Ixodes scapularis (Ixodida, Ixodidae), is one of the major disease vectors in the United States, and due to multiple human impact factors, such as decreasing forest size for land development and climate change, it has expanded its range and established across the United States. Throughout the life cycle, ticks locate hosts for their blood-meal, and although the ecologies of this tick and their hosts have been studied in depth, the sensory physiology behind host location largely remains unexplored. Here, we report establishing a robust paradigm to isolate and identify odors from the natural milieu for I. scapularis. We performed single sensillum recordings (SSR) from the olfactory sensilla on the tick tarsi, and used the SSR system as a biological detector to isolate natural compounds that elicited biological activity. The SSR setup was further tested in tandem with gas chromatography (GC) wherein the ticks' olfactory sensillum activity served as a biological detector. The GC-SSR recordings from the wall pore sensilla in the Haller's organ, and further identification of the biologically active deer gland constituents by GC-mass spectrometry (GC-MS) revealed methyl substituted phenols as strong chemostimuli, as compared to ethyl or propyl substitutions. The strongest electrophysiological activity was elicited by m- cresol followed by p- cresol. Ethyl- and propylphenols with any of the three substitutions (ortho, meta or para), did not induce any neurophysiological activity. Finally, a behavioral analysis in a dual-choice olfactometer of all these phenols at three different doses revealed no significant behavioral response, except for p- cresol at -3 dilution. Overall, this study contributes to our understanding of I. scapularis tick's neurophysiology and provides a robust platform to isolate and identify natural attractants and repellents.
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Affiliation(s)
- Tanya Josek
- Center of Mathematics, Science, and Technology, Illinois State University, Normal, IL 61790, USA
| | - Jared Sperrazza
- Department of Entomology, University of Kentucky, Lexington, KY 40546, USA
| | - Marianne Alleyne
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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20
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Poh KC, Skvarla M, Evans JR, Machtinger ET. Collecting Deer Keds (Diptera: Hippoboscidae: Lipoptena Nitzsch, 1818 and Neolipoptena Bequaert, 1942) and Ticks (Acari: Ixodidae) From Hunter-Harvested Deer and Other Cervids. JOURNAL OF INSECT SCIENCE (ONLINE) 2020; 20:5948068. [PMID: 33135746 PMCID: PMC7604836 DOI: 10.1093/jisesa/ieaa024] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Indexed: 05/29/2023]
Abstract
Deer keds (Diptera: Hippoboscidae: Lipoptena Nitzsch, 1818 and Neolipoptena Bequaert, 1942) are blood-feeding ectoparasites that primarily attack cervids and occasionally bite humans, while ticks may be found on cervids, but are more generalized in host choice. Recent detection of pathogens such as Anaplasma and Borrelia in deer keds and historical infections of tick-borne diseases provides reason to investigate these ectoparasites as vectors. However, previous methods employed to sample deer keds and ticks vary, making it difficult to standardize and compare ectoparasite burdens on cervids. Therefore, we propose a standardized protocol to collect deer keds and ticks from hunter-harvested deer, which combines previous methods of sampling, including timing of collections, dividing sections of the deer, and materials used in the collection process. We tested a three-section and a five-section sampling scheme in 2018 and 2019, respectively, and found that dividing the deer body into five sections provided more specificity in identifying where deer keds and ticks may be found on deer. Data from 2018 suggested that deer keds and ticks were found on all three sections (head, anterior, posterior), while data from 2019 suggested that more Ixodes scapularis were found on the head and deer keds were found on all body sections (head, dorsal anterior, dorsal posterior, ventral anterior, and ventral posterior). The protocol provides an efficient way to sample deer for deer keds and ticks and allows researchers to compare ectoparasite burdens across geographical regions. Furthermore, this protocol can be used to collect other ectoparasites from deer or other cervids.
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Affiliation(s)
- Karen C Poh
- Department of Entomology, Penn State University, University Park, PA
| | - Michael Skvarla
- Department of Entomology, Penn State University, University Park, PA
| | - Jesse R Evans
- Department of Entomology, Penn State University, University Park, PA
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21
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Interrupted Blood Feeding in Ticks: Causes and Consequences. Microorganisms 2020; 8:microorganisms8060910. [PMID: 32560202 PMCID: PMC7355616 DOI: 10.3390/microorganisms8060910] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 06/12/2020] [Accepted: 06/14/2020] [Indexed: 01/02/2023] Open
Abstract
Ticks are obligate hematophagous arthropods and act as vectors for a great variety of pathogens, including viruses, bacteria, protozoa, and helminths. Some tick-borne viruses, such as Powassan virus and tick-borne encephalitis virus, are transmissible within 15–60 min after tick attachment. However, a minimum of 3–24 h of tick attachment is necessary to effectively transmit bacterial agents such as Ehrlichia spp., Anaplasma spp., and Rickettsia spp. to a new host. Longer transmission periods were reported for Borrelia spp. and protozoans such as Babesia spp., which require a minimum duration of 24–48 h of tick attachment for maturation and migration of the pathogen. Laboratory observations indicate that the probability of transmission of tick-borne pathogens increases with the duration an infected tick is allowed to remain attached to the host. However, the transmission time may be shortened when partially fed infected ticks detach from their initial host and reattach to a new host, on which they complete their engorgement. For example, early transmission of tick-borne pathogens (e.g., Rickettsia rickettsii, Borrelia burgdorferi, and Babesia canis) and a significantly shorter transmission time were demonstrated in laboratory experiments by interrupted blood feeding. The relevance of such situations under field conditions remains poorly documented. In this review, we explore parameters of, and causes leading to, spontaneous interrupted feeding in nature, as well as the effects of this behavior on the minimum time required for transmission of tick-borne pathogens.
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Ferreira LL, de Oliveira Filho JG, de Oliveira Silva F, Lacerda Ferraz AL, Mascarin GM. Attract or repel Amblyomma sculptum ticks: Screening of semiochemicals. Vet Parasitol 2020; 278:109036. [PMID: 32004852 DOI: 10.1016/j.vetpar.2020.109036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/18/2020] [Accepted: 01/20/2020] [Indexed: 12/01/2022]
Abstract
Amblyomma sculptum is a tick of medical-veterinary importance. Areas with high infestations need to be monitored, and parasitized hosts treated accordingly. Carbon dioxide (CO2) traps and acaricides are commonly deployed as control measures, although with some disadvantages such as high costs, challenging logistics and vertebrate intoxication. Semiochemicals have the potential to improve tick attraction to traps and monitoring devices and alleviate the burden of A. sculptum infestations. Four concentrations (10, 5, 2.5 and 1.25 %) of 13 semiochemical candidates (CO2 only at 5 % as the standard, benzaldehyde, benzoic acid, salicylic acid, 2,6 diclorophenol, R-limonene, S-limonene, methyl salicylate, 1-octen-3-ol, acetone, ammonium hydroxide, isobutyric acid and lactic acid) were tested on unfed A. sculptum nymphs and adults using a Y-tube olfactometer to evaluated repellence and attraction behaviors. All stages tested were attracted to CO2, whereas nymphs were repelled by benzaldehyde and R-limonene, both at 10 %, and isobutyric acid at 5 and 10 %. Nymphs were attracted by methyl salicylate, benzoic acid and salicylic acid, all at 1.25 %, and by ammonium hydroxide at 2.5 %. Males were attracted by benzoic acid at 2.5 %, while females were repelled by benzaldehyde at 5 %. Mixtures with the attractive compounds achieved no attraction response. The compounds that caused attractiveness in the olfactometer assay (CO2, methyl salicylate, benzoic acid, salicylic acid and ammonium hydroxide) were placed randomly in traps in a grassland plot naturally infested with A. sculptum in triplicate. Notably, dry ice (CO2) remained the best at luring ticks in the field (P < 0.001). Benzoic acid should be further investigated since attractant activity was strongly confirmed in both laboratory and field tests. On the other hand, isobutyric acid and R-limonene could be better exploited due to their repellent role revealed by the lab assay, which makes them worthwhile molecules as natural repellents for the management of this tick.
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Affiliation(s)
- Lorena Lopes Ferreira
- Escola de Veterinária, Campus Pampulha, Avenida Antônio Carlos 6627, CP 567, CEP 31270-901, Belo Horizonte, Minas Gerais, Brazil.
| | - Jaires Gomes de Oliveira Filho
- Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Campus Samambaia, Avenida Esperança, s/n, Campus Universitário, CEP: 74690-900, Goiânia, Goiás, Brazil.
| | - Fernanda de Oliveira Silva
- Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Campus Samambaia, Avenida Esperança, s/n, Campus Universitário, CEP: 74690-900, Goiânia, Goiás, Brazil.
| | - Ana Livia Lacerda Ferraz
- Clarion Biociências Ltda, Rua 11, Qd 7. Lt 47 a 55, Polo Empresarial de Goiás, Aparecida de Goiânia, Goiás, Brazil.
| | - Gabriel Moura Mascarin
- Empresa Brasileira de Pesquisa Agropecuária - Embrapa Meio Ambiente, Rodovia SP 340, km 127,5, CP 69, CEP: 13820-000, Jaguariúna, São Paulo, Brazil.
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Innovative way to dispense pheromones for off-host control of Rhipicephalus sanguineus sensu lato ticks. Vet Parasitol 2019; 275:108936. [PMID: 31669835 DOI: 10.1016/j.vetpar.2019.108936] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 09/30/2019] [Accepted: 10/03/2019] [Indexed: 11/20/2022]
Abstract
Vapour patches dispensing pheromones were evaluated as lures to increase the attractiveness of sticky tick traps for Rhipicephalus sanguineus sensu lato (s.l.). Sex pheromone (SP), assembly pheromone (AP) and a combination of SP + AP at optimal concentrations were impregnated in vapour patches. The responses of the different stages of R. sanguineus s.l. (i.e. larvae, nymphs and adults) to the pheromones were evaluated using a Petri dish bioassay. The impregnated vapour patches were retained as such for a period of two mo and their efficacy was reassessed. In a subsequent field trial, pheromone impregnated vapour patches were placed as lures in bamboo (Bambusa vulgaris) sticky traps designed for the control of ticks in dog kennels. In vitro AP impregnated vapour patches were effective in attracting the different life stages of R. sanguineus s.l. whereas SP was effective in attracting the unfed and fed male stages of R. sanguineus s.l. The field trial revealed that questing and engorged larvae, nymphs and females of R. sanguineus s.l. were attracted more towards AP impregnated vapour patches than SP and AP + SP impregnated vapour patches. Fed and unfed male ticks were lured effectively by SP alone. The combination of SP + AP revealed no potent additive or synergistic effect.
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Dunn JA, Prickett JC, Collins DA, Macarthur R, Weaver RJ. Choice test to determine potential attractants and repellents for the sheep scab mite, Psoroptes ovis (Acari: Psoroptidae). EXPERIMENTAL & APPLIED ACAROLOGY 2019; 79:187-194. [PMID: 31598890 DOI: 10.1007/s10493-019-00416-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 09/06/2019] [Indexed: 06/10/2023]
Abstract
A choice test bioassay was devised to screen compounds as potential semiochemicals (e.g., kairomones or allomones that mediate aggregation, attraction or repellence) for the obligate parasitic mite, Psoroptes ovis. The choice test used filter paper discs in a 1:4 test:control ratio and was found to be a reliable, effective and efficient method. Four mammalian lipid components were assessed as potential attractants-linoleic acid, arachidonic acid, methyl myristate and squalene-, and the insect/tick repellent DEET for potential repellence. Linoleic acid was significantly attractive to P. ovis adult females and has the potential to act as an attractant. Identification of P. ovis semiochemicals, especially attractants, would be beneficial in the development of novel control methods and tools for this species. This is essential considering the increase in resistance to the limited prophylactic chemical treatments in the UK, and the high prevalence of scab infections.
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Affiliation(s)
- J A Dunn
- Fera Science Ltd., Sand Hutton, York, YO41 1LZ, UK.
| | - J C Prickett
- Fera Science Ltd., Sand Hutton, York, YO41 1LZ, UK
| | - D A Collins
- Fera Science Ltd., Sand Hutton, York, YO41 1LZ, UK
| | - R Macarthur
- Fera Science Ltd., Sand Hutton, York, YO41 1LZ, UK
| | - R J Weaver
- Fera Science Ltd., Sand Hutton, York, YO41 1LZ, UK
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Xiu C, Xiao Y, Zhang S, Bao H, Liu Z, Zhang Y. Niemann-Pick proteins type C2 are identified as olfactory related genes of Pardosa pseudoannulata by transcriptome and expression profile analysis. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2019; 29:320-329. [PMID: 30669056 DOI: 10.1016/j.cbd.2019.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 11/26/2018] [Accepted: 01/09/2019] [Indexed: 01/24/2023]
Abstract
In arthropods, the large majority of studies on olfaction have been mainly focused on insects, whereas little on Arachnida, even though olfaction is very important in arachnid behavior. Pardosa pseudoannulata is one of the most common wandering spiders in rice fields, as the important natural enemy against a range of pests. However, little is known about the potential chemosensory proteins involved in olfactory behavior of these spiders. Niemann-Pick proteins type C2 (NPC2) as a new class of binding and transport proteins for semiochemicals in arthropods especially ticks and mites has received more attention in recent years. In this study, six NPC2s namely PpseNPC1-6 were newly identified in the appendages of P. pseudoannulata based on transcriptome data. A phylogenetic analysis indicated that all of P. pseudoannulata NPC2s were clustered together forming one clade with high posterior probability values. In addition, the sequences shared the same subclade with the NPC2 sequences of ticks and scorpion. The motif-patterns indicated that PpseNPC2-5 had the common pattern with the two-spotted spider mite Tetranychus urticae and the ant Trachymyrmex cornetzi. Furthermore, quantitative real-time PCR (qPCR) measurements were conducted to evaluate the expression profile of these genes in various tissues of P. pseudoannulata. It was found that most NPC2s (PpseNPC2-1, PpseNPC2-2, PpseNPC2-5 and PpseNPC2-6) were highly expressed in adult pedipalps and chelicerae. Owing to the functional olfactory organs in Chelicerata of pedipalps, our results supported a putative role of NPC2s as new odorant carriers in P. pseudoannulata.
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Affiliation(s)
- Chunli Xiu
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yong Xiao
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Song Zhang
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China
| | - Haibo Bao
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China
| | - Zewen Liu
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China.
| | - Yongjun Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
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Burrow HM, Mans BJ, Cardoso FF, Birkett MA, Kotze AC, Hayes BJ, Mapholi N, Dzama K, Marufu MC, Githaka NW, Djikeng A. Towards a new phenotype for tick resistance in beef and dairy cattle: a review. ANIMAL PRODUCTION SCIENCE 2019. [DOI: 10.1071/an18487] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
About 80% of the world’s cattle are affected by ticks and tick-borne diseases, both of which cause significant production losses. Cattle host resistance to ticks is the most important factor affecting the economics of tick control, but it is largely neglected in tick-control programs due to technical difficulties and costs associated with identifying individual-animal variation in resistance. The present paper reviews the scientific literature to identify factors affecting resistance of cattle to ticks and the biological mechanisms of host tick resistance, to develop alternative phenotype(s) for tick resistance. If new cost-effective phenotype(s) can be developed and validated, then tick resistance of cattle could be genetically improved using genomic selection, and incorporated into breeding objectives to simultaneously improve cattle productive attributes and tick resistance. The phenotype(s) could also be used to improve tick control by using cattle management. On the basis of the present review, it is recommended that three possible phenotypes (haemolytic analysis; measures of skin hypersensitivity reactions; simplified artificial tick infestations) be further developed to determine their practical feasibility for consistently, cost-effectively and reliably measuring cattle tick resistance in thousands of individual animals in commercial and smallholder farmer herds in tropical and subtropical areas globally. During evaluation of these potential new phenotypes, additional measurements should be included to determine the possibility of developing a volatile-based resistance phenotype, to simultaneously improve cattle resistance to both ticks and biting flies. Because the current measurements of volatile chemistry do not satisfy the requirements of a simple, cost-effective phenotype for use in commercial cattle herds, consideration should also be given to inclusion of potentially simpler measures to enable indirect genetic selection for volatile-based resistance to ticks.
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Benelli G. Managing mosquitoes and ticks in a rapidly changing world - Facts and trends. Saudi J Biol Sci 2018; 26:921-929. [PMID: 31303820 PMCID: PMC6600734 DOI: 10.1016/j.sjbs.2018.06.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 06/06/2018] [Accepted: 06/26/2018] [Indexed: 02/08/2023] Open
Abstract
Vector-borne diseases transmitted by mosquitoes and ticks are on the rise. The effective and sustainable control of these arthropod vectors is a puzzling challenge for public health worldwide. In the present review, I attempted to provide a concise and updated overview of the current mosquito and tick research scenario. The wide array of control tools recently developed has been considered, with special reference to those approved by the World Health Organization Vector Control Advisory Group (WHO VCAG), as well as novel ones with an extremely promising potential to be exploited in vector control programs. Concerning mosquitoes, a major focus has been given on genetically modified vectors, eave tubes, attractive toxic sugar baits (ATSB) and biocontrol agents. Regarding ticks, the recent development of highly effective repellents and acaricides (including nanoformulated ones) as well as behavior-based control tools, has been highlighted. In the second part of the review, key research questions about biology and control of mosquitoes and ticks have been critically formulated. A timely research agenda outlining hot issues to be addressed in mosquito and tick research is provided. Overall, it is expected that the present review will contribute to boost research and applications on successful mosquito and tick control strategies, along with an improved knowledge of their biology and ecology.
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Affiliation(s)
- Giovanni Benelli
- Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy.,The BioRobotics Institute, Sant'Anna School of Advanced Studies, viale Rinaldo Piaggio 34, 56025, Pontedera, Pisa, Italy
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Benelli G, Pavela R. Repellence of essential oils and selected compounds against ticks-A systematic review. Acta Trop 2018; 179:47-54. [PMID: 29287758 DOI: 10.1016/j.actatropica.2017.12.025] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Revised: 12/11/2017] [Accepted: 12/23/2017] [Indexed: 01/17/2023]
Abstract
Ticks act as vectors of a wide range of infectious agents, far encompassing any other group of bloodsucking arthropods worldwide. The prevention of tick-borne diseases is strictly linked to the successful management of tick vector populations. The employ of repellents can represent a worth solution to avoid tick bites. It is widely adopted to protect travellers and pets exposed to ticks during limited periods of the year. The use of natural products as active ingredients in eco-friendly repellent formulations is currently a prominent research area, due to the wide diversity and high effectiveness of a number of plant-borne compounds, with special reference to essential oils (EOs) extracted from medicinal and aromatic species. Here, we reviewed current knowledge available on EOs tested as repellents against tick species of veterinary importance. Furthermore, we analysed the effectiveness of pure compounds isolated from EOs as tick repellents and their potential implications for practical use in the öreal world". A quantitative analysis of literature available is this research field was provided, along with its impact (i.e., in terms of citations over time) on the scientific community of researchers in tick control science and natural product chemistry. In the final sections, future outlooks are highlighted. We discussed major challenges to stabilize the most effective EOs and pure molecules, explore the synergistic and antagonistic effects in blends of EOs and/or pure constituents, standardize currently adopted testing methods, and evaluate non-target risks of herbal repellents.
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Williamson BN, Schwan TG. Conspecific hyperparasitism: An alternative route for Borrelia hermsii transmission by the tick Ornithodoros hermsi. Ticks Tick Borne Dis 2017; 9:334-339. [PMID: 29174448 DOI: 10.1016/j.ttbdis.2017.11.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 11/06/2017] [Accepted: 11/15/2017] [Indexed: 10/18/2022]
Abstract
Ixodid and argasid ticks may hyperparasitize other individuals of their own species to acquire a blood meal, however most accounts are based on single observations and the behavior has rarely been studied. While maintaining laboratory colonies of Ornithodoros species, we noticed that unfed ticks occasionally fed on other ticks that were feeding on mice, and unfed ticks parasitized engorged ticks when confined together in tubes. Therefore, we investigated hyperparasitism by Ornithodoros hermsi and the ability of these ticks to acquire and transmit the relapsing fever spirochete Borrelia hermsii when feeding on other ticks. Various combinations of unfed and recently engorged male, female and nymphal ticks were confined for 1-2h as individual pairs or in groups, then examined to determine the number of ticks that acquired blood by feeding on others. Unfed O. hermsi males were far more likely to hyperparasitize other ticks than were females and nymphs, as 78.6% of males (114 of 145 ticks) fed when confined with recently engorged ticks. Unfed females and nymphs also hyperparasitized other ticks but far less frequently (only 6.7% combined; 17 of 254 ticks). Infection experiments demonstrated that unfed males acquired B. hermsii when parasitizing nymphs that had recently engorged on a spirochetemic mouse, and unfed infected males transmitted spirochetes to recently engorged nymphs. Some ticks infected via hyperparasitism subsequently transmitted B. hermsii to mice. Hyperparasitism by O. hermsi occurred more frequently than expected, although possibly influenced by our experimental design. The significance of this behavior as it may influence the horizontal transfer of B. hermsii in nature is not known but worthy of future consideration.
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Affiliation(s)
- Brandi N Williamson
- Laboratory of Zoonotic Pathogens, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, MT, United States.
| | - Tom G Schwan
- Laboratory of Zoonotic Pathogens, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, MT, United States
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Nanoparticles as effective acaricides against ticks—A review. Ticks Tick Borne Dis 2017; 8:821-826. [DOI: 10.1016/j.ttbdis.2017.08.004] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 08/09/2017] [Accepted: 08/10/2017] [Indexed: 12/14/2022]
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Jirošová A, Jančařík A, Menezes RC, Bazalová O, Dolejšová K, Vogel H, Jedlička P, Buček A, Brabcová J, Majer P, Hanus R, Svatoš A. Co-option of the sphingolipid metabolism for the production of nitroalkene defensive chemicals in termite soldiers. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017; 82:52-61. [PMID: 28126587 DOI: 10.1016/j.ibmb.2017.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/20/2017] [Accepted: 01/20/2017] [Indexed: 06/06/2023]
Abstract
The aliphatic nitroalkene (E)-1-nitropentadec-1-ene (NPD), reported in early seventies in soldiers of the termite genus Prorhinotermes, was the first documented nitro compound produced by insects. Yet, its biosynthetic origin has long remained unknown. Here, we investigated in detail the biosynthesis of NPD in P. simplex soldiers. First, we track the dynamics in major metabolic pathways during soldier ontogeny, with emphasis on likely NPD precursors and intermediates. Second, we propose a hypothesis of NPD formation and verify its individual steps using in vivo incubations of putative precursors and intermediates. Third, we use a de novo assembled RNA-Seq profiles of workers and soldiers to identify putative enzymes underlying NPD formation. And fourth, we describe the caste- and age-specific expression dynamics of candidate initial genes of the proposed biosynthetic pathway. Our observations provide a strong support to the following biosynthetic scenario of NPD formation, representing an analogy of the sphingolipid pathway starting with the condensation of tetradecanoic acid with l-serine and leading to the formation of a C16 sphinganine. The C16 sphinganine is then oxidized at the terminal carbon to give rise to 2-amino-3-hydroxyhexadecanoic acid, further oxidized to 2-amino-3-oxohexadecanoic acid. Subsequent decarboxylation yields 1-aminopentadecan-2-one, which then proceeds through six-electron oxidation of the amino moiety to give rise to 1-nitropentadecan-2-one. Keto group reduction and hydroxyl moiety elimination lead to NPD. The proposed biosynthetic sequence has been constructed from age-related quantitative dynamics of individual intermediates and confirmed by the detection of labeled products downstream of the administered labeled intermediates. Comparative RNA-Seq analyses followed by qRT-PCR validation identified orthologs of serine palmitoyltransferase and 3-ketodihydrosphingosine reductase genes as highly expressed in the NPD production site, i.e. the frontal gland of soldiers. A dramatic onset of expression of the two genes in the first days of soldier's life coincides with the start of NPD biosynthesis, giving further support to the proposed biosynthetic hypothesis.
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Affiliation(s)
- Anna Jirošová
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia
| | - Andrej Jančařík
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia
| | - Riya C Menezes
- Max-Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
| | - Olga Bazalová
- Biology Centre CAS, Branišovská 31, CZ-37005 České Budějovice, Czechia
| | - Klára Dolejšová
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia; Faculty of Science, Charles University in Prague, Viničná 7, 128 44 Prague, Czechia
| | - Heiko Vogel
- Max-Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
| | - Pavel Jedlička
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia
| | - Aleš Buček
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia
| | - Jana Brabcová
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia
| | - Pavel Majer
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia
| | - Robert Hanus
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia.
| | - Aleš Svatoš
- The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague, Czechia; Max-Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany.
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Olson JF, Vers LMV, Moon RD, Kells SA. Two compounds in bed bug feces are sufficient to elicit off-host aggregation by bed bugs, Cimex lectularius. PEST MANAGEMENT SCIENCE 2017; 73:198-205. [PMID: 27060680 DOI: 10.1002/ps.4286] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 05/26/2023]
Abstract
BACKGROUND After feeding, bed bugs aggregate in cracks and crevices near a host. Aggregation and arrestment are mediated by tactile and chemical stimuli associated with the bugs' feces and exuviae. Volatiles derived from fecally stained filter papers were analyzed by solid-phase microextraction (SPME) and evaluated using a multichoice behavioral assay to determine their impact on bed bug aggregation. In addition, crude fecal extracts were collected in methanol, analyzed by gas chromatography coupled with electroantennogram detection (GC-EAD) and mass spectrometry (GC-MS) and evaluated in open-air multichoice behavioral assays. RESULTS The SPME method was used to detect (E)-2-hexenal and (E)-2-octenal in heated bed bug feces. The presence of these two volatile components did not affect aggregation. Analysis of the crude fecal extracts revealed several semi-volatile nitrogenous compounds, a carboxylic acid and a sulfur-based compound. Adult antennae responded to compounds eluted from three regions of the crude extract using GC-EAD. A combination of two compounds, dimethyl trisulfide and methyldiethanolamine, resulted in aggregation responses equivalent to the original crude extract. CONCLUSION Bed bug aggregation is mediated by semi-volatile compounds derived from fecal extracts, and two compounds are sufficient to elicit aggregation. The two compounds identified here could be used to enhance the effectiveness of insecticidal applications or improve monitoring techniques. © 2016 Society of Chemical Industry.
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Affiliation(s)
- Joelle F Olson
- Department of Entomology, University of Minnesota, St Paul, MN, USA
| | | | - Roger D Moon
- Department of Entomology, University of Minnesota, St Paul, MN, USA
| | - Stephen A Kells
- Department of Entomology, University of Minnesota, St Paul, MN, USA
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Pavela R, Canale A, Mehlhorn H, Benelli G. Application of ethnobotanical repellents and acaricides in prevention, control and management of livestock ticks: A review. Res Vet Sci 2016; 109:1-9. [DOI: 10.1016/j.rvsc.2016.09.001] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 08/25/2016] [Accepted: 09/06/2016] [Indexed: 12/30/2022]
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Benelli G. Tools to fight ticks: A never-ending story? News from the front of green acaricides and photosensitizers. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2016. [DOI: 10.1016/s2222-1808(16)61105-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Carr AL, Roe M. Acarine attractants: Chemoreception, bioassay, chemistry and control. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2016; 131:60-79. [PMID: 27265828 PMCID: PMC4900186 DOI: 10.1016/j.pestbp.2015.12.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 06/26/2015] [Accepted: 12/24/2015] [Indexed: 05/30/2023]
Abstract
The Acari are of significant economic importance in crop production and human and animal health. Acaricides are essential for the control of these pests, but at the same time, the number of available pesticides is limited, especially for applications in animal production. The Acari consist of two major groups, the mites that demonstrate a wide variety of life strategies, i.e., herbivory, predation and ectoparasitism, and ticks which have evolved obligatory hematophagy. The major sites of chemoreception in the acarines are the chelicerae, palps and tarsi on the forelegs. A unifying name, the "foretarsal sensory organ" (FSO), is proposed for the first time in this review for the sensory site on the forelegs of all acarines. The FSO has multiple sensory functions including olfaction, gustation, and heat detection. Preliminary transcriptomic data in ticks suggest that chemoreception in the FSO is achieved by a different mechanism from insects. There are a variety of laboratory and field bioassay methods that have been developed for the identification and characterization of attractants but minimal techniques for electrophysiology studies. Over the past three to four decades, significant progress has been made in the chemistry and analysis of function for acarine attractants in mites and ticks. In mites, attractants include aggregation, immature female, female sex and alarm pheromones; in ticks, the attraction-aggregation-attachment, assembly and sex pheromones; in mites and ticks host kairomones and plant allomones; and in mites, fungal allomones. There are still large gaps in our knowledge of chemical communication in the acarines compared to insects, especially relative to acarine pheromones, and more so for mites than ticks. However, the use of lure-and-kill and lure-enhanced biocontrol strategies has been investigated for tick and mite control, respectively, with significant environmental advantages which warrant further study.
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Affiliation(s)
- Ann L Carr
- Department of Entomology, North Carolina State University, Campus Box 7647, Raleigh, NC 27695-7647, USA
| | - Michael Roe
- Department of Entomology, North Carolina State University, Campus Box 7647, Raleigh, NC 27695-7647, USA.
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Reisenman CE, Lei H, Guerenstein PG. Neuroethology of Olfactory-Guided Behavior and Its Potential Application in the Control of Harmful Insects. Front Physiol 2016; 7:271. [PMID: 27445858 PMCID: PMC4928593 DOI: 10.3389/fphys.2016.00271] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 06/16/2016] [Indexed: 11/26/2022] Open
Abstract
Harmful insects include pests of crops and storage goods, and vectors of human and animal diseases. Throughout their history, humans have been fighting them using diverse methods. The fairly recent development of synthetic chemical insecticides promised efficient crop and health protection at a relatively low cost. However, the negative effects of those insecticides on human health and the environment, as well as the development of insect resistance, have been fueling the search for alternative control tools. New and promising alternative methods to fight harmful insects include the manipulation of their behavior using synthetic versions of "semiochemicals", which are natural volatile and non-volatile substances involved in the intra- and/or inter-specific communication between organisms. Synthetic semiochemicals can be used as trap baits to monitor the presence of insects, so that insecticide spraying can be planned rationally (i.e., only when and where insects are actually present). Other methods that use semiochemicals include insect annihilation by mass trapping, attract-and- kill techniques, behavioral disruption, and the use of repellents. In the last decades many investigations focused on the neural bases of insect's responses to semiochemicals. Those studies help understand how the olfactory system detects and processes information about odors, which could lead to the design of efficient control tools, including odor baits, repellents or ways to confound insects. Here we review our current knowledge about the neural mechanisms controlling olfactory responses to semiochemicals in harmful insects. We also discuss how this neuroethology approach can be used to design or improve pest/vector management strategies.
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Affiliation(s)
- Carolina E. Reisenman
- Department of Molecular and Cell Biology and Essig Museum of Entomology, University of California, BerkeleyBerkeley, CA, USA
| | - Hong Lei
- Department of Neuroscience, University of ArizonaTucson, AZ, USA
| | - Pablo G. Guerenstein
- Lab. de Estudio de la Biología de Insectos, CICyTTP-CONICETDiamante, Argentina
- Facultad de Ingeniería, Universidad Nacional de Entre RíosOro Verde, Argentina
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Borges LMF, Li AY, Olafson PU, Renthal R, Bauchan GR, Lohmeyer KH, León AAPD. Neuronal projections from the Haller's organ and palp sensilla to the synganglion of Amblyomma americanum§. REVISTA BRASILEIRA DE PARASITOLOGIA VETERINARIA 2016; 25:217-24. [DOI: 10.1590/s1984-29612016039] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 04/11/2016] [Indexed: 11/22/2022]
Abstract
Abstract The present study was conducted to elucidate the neuronal pathways between peripheral olfactory and taste sensilla and the synganglion in an Ixodidae tick species. The tarsus of the front legs (olfactory nerves) and the fourth palpal segment (gustatory nerves) of unfed Amblyomma americanum males and females were excised. A neuronal tracer, dextran tetramethylrhodamine, was used for filling of the sensory neurons. The synganglion preparations were examined using a confocal microscope. Neuronal arborizations from the Haller’s organ were confined to the olfactory lobes and the first pedal ganglion. The estimated number of olfactory glomeruli ranged from 16 to 22 per olfactory lobe in the females. The number of glomeruli was not counted in males because they were densely packed. Sensory neurons associated with sensilla at the distal end of the palpal organ projected into the palpal ganglion in the synganglion through the palpal nerve. Gustatory sensory neurons associated with palpal sensilla projected into a commissure with several bulges, which are confined in the palpal ganglion. The findings of distinct projection patterns of sensory neurons associated with the Haller’s organ and palpal organ in the lone star tick from this study advanced our knowledge on mechanisms of sensory information processing in ticks.
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Boxler B, Odermatt P, Haag-Wackernagel D. Host finding of the pigeon tick Argas reflexus. MEDICAL AND VETERINARY ENTOMOLOGY 2016; 30:193-199. [PMID: 26959079 DOI: 10.1111/mve.12165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 01/07/2016] [Accepted: 01/08/2016] [Indexed: 06/05/2023]
Abstract
The medically and veterinary important feral pigeon tick Argas reflexus (Ixodida: Argasidae) Fabricius usually feeds on pigeons, but if its natural hosts are not available, it also enters dwellings to bite humans that can possibly react with severe allergic reactions. Argas reflexus is ecologically extremely successful as a result of some outstanding morphological, physiological, and ethological features. Yet, it is still unknown how the pigeon tick finds its hosts. Here, different host stimuli such as living nestlings as well as begging calls, body heat, smell, host breath and tick faeces, were tested under controlled laboratory conditions. Of all stimuli tested, only heat played a role in host-finding. The heat stimulus was then tested under natural conditions within a pigeon loft. The results showed that A. reflexus is able to find a host over short distances of only a few centimetres. Furthermore, it finds its host by random movements and recognizes a host only right before direct contact is made. The findings are useful for the control of A. reflexus in infested apartments, both to diagnose an infestation and to perform a success monitoring after disinfestation.
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Affiliation(s)
- B Boxler
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - P Odermatt
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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de Oliveira Filho JG, Sarria ALF, Ferreira LL, Caulfield JC, Powers SJ, Pickett JA, de León AAP, Birkett MA, Borges LMF. Quantification of brown dog tick repellents, 2-hexanone and benzaldehyde, and release from tick-resistant beagles, Canis lupus familiaris. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1022:64-69. [DOI: 10.1016/j.jchromb.2016.03.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 03/11/2016] [Accepted: 03/15/2016] [Indexed: 10/22/2022]
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Benelli G, Pavela R, Canale A, Mehlhorn H. Tick repellents and acaricides of botanical origin: a green roadmap to control tick-borne diseases? Parasitol Res 2016; 115:2545-60. [PMID: 27146901 DOI: 10.1007/s00436-016-5095-1] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 04/26/2016] [Indexed: 01/19/2023]
Abstract
Arthropods are dangerous vectors of agents of deadly diseases, which may hit as epidemics or pandemics in the increasing world population of humans and animals. Among them, ticks transmit more pathogen species than any other group of blood-feeding arthropods worldwide. Thus, the effective and eco-friendly control of tick vectors in a constantly changing environment is a crucial challenge. A number of novel routes have been attempted to prevent and control tick-borne diseases, including the development of (i) vaccines against viruses vectored by ticks; (ii) pheromone-based control tools, with special reference to the "lure and kill" techniques; (iii) biological control programmes relying on ticks' natural enemies and pathogens; and (iv) the integrated pest management practices aimed at reducing tick interactions with livestock. However, the extensive employment of acaricides and tick repellents still remains the two most effective and ready-to-use strategies. Unfortunately, the first one is limited by the rapid development of resistance in ticks, as well as by serious environmental concerns. On the other hand, the exploitation of plants as sources of effective tick repellents is often promising. Here, we reviewed current knowledge concerning the effectiveness of plant extracts as acaricides or repellents against tick vectors of public health importance, with special reference to Ixodes ricinus, Ixodes persulcatus, Amblyomma cajennense, Haemaphysalis bispinosa, Haemaphysalis longicornis, Hyalomma anatolicum, Hyalomma marginatum rufipes, Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) microplus, Rhipicephalus pulchellus, Rhipicephalus sanguineus and Rhipicephalus turanicus. Eighty-three plant species from 35 botanical families were selected. The most frequent botanical families exploited as sources of acaricides and repellents against ticks were Asteraceae (15 % of the selected studies), Fabaceae (9 %), Lamiaceae (10 %), Meliaceae (5 %), Solanaceae (6 %) and Verbenaceae (5 %). Regression equation analyses showed that the literature grew by approximately 20 % per year (period: 2005-2015). Lastly, in the final section, insights for future research are discussed. We focused on some caveats for future data collection and analysis. Current critical points mainly deal with (a) not uniform methods used, which prevent proper comparison of the results; (b) inaccurate tested concentrations, frequently 100 % concentration corresponded to the gross extract, where the exact amounts of extracted substances are unknown; and (c) not homogeneous size of tested tick instars and species. Overall, the knowledge summarized in this review may be helpful for comparative screening among extensive numbers of plant-borne preparations, in order to develop newer and safer tick control tools.
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Affiliation(s)
- Giovanni Benelli
- Insect Behaviour Group, Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124, Pisa, Italy.
| | - Roman Pavela
- Crop Research Institute, Drnovska 507, 161 06, Prague 6, Czech Republic
| | - Angelo Canale
- Insect Behaviour Group, Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124, Pisa, Italy
| | - Heinz Mehlhorn
- Department of Parasitology, Heinrich Heine University, Düsseldorf, 40225, Germany
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Carr AL, Sonenshine DE, Strider JB, Roe RM. Evidence of female sex pheromones and characterization of the cuticular lipids of unfed, adult male versus female blacklegged ticks, Ixodes scapularis. EXPERIMENTAL & APPLIED ACAROLOGY 2016; 68:519-538. [PMID: 26864785 PMCID: PMC4785100 DOI: 10.1007/s10493-015-0009-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 06/15/2015] [Indexed: 06/01/2023]
Abstract
Copulation in Ixodes scapularis involves physical contact between the male and female (on or off the host), male mounting of the female, insertion/maintenance of the male chelicerae in the female genital pore (initiates spermatophore production), and the transfer of the spermatophore by the male into the female genital pore. Bioassays determined that male mounting behavior/chelicerae insertion required direct contact with the female likely requiring non-volatile chemical cues with no evidence of a female volatile sex pheromone to attract males. Unfed virgin adult females and replete mated adult females elicited the highest rates of male chelicerae insertion with part fed virgin adult females exhibiting a much lower response. Whole body surface hexane extracts of unfed virgin adult females and males, separately analyzed by GC-MS, identified a number of novel tick surface associated compounds: fatty alcohols (1-hexadecanol and 1-heptanol), a fatty amide (erucylamid), aromatic hydrocarbons, a short chain alkene (1-heptene), and a carboxylic acid ester (5β-androstane). These compounds are discussed in terms of their potential role in female-male communication. The two most abundant fatty acid esters found were butyl palmitate and butyl stearate present in ratios that were sex specific. Only 6 n-saturated hydrocarbons were identified in I. scapularis ranging from 10 to 18 carbons.
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Affiliation(s)
- Ann L Carr
- Department of Entomology, North Carolina State University, Campus Box 7647, Raleigh, NC, 27695-7647, USA
| | - Daniel E Sonenshine
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, 23529, USA
| | - John B Strider
- Department of Entomology, North Carolina State University, Campus Box 7647, Raleigh, NC, 27695-7647, USA
| | - R Michael Roe
- Department of Entomology, North Carolina State University, Campus Box 7647, Raleigh, NC, 27695-7647, USA.
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Clarke GS, Crossland MR, Shine R. Can we control the invasive cane toad using chemicals that have evolved under intraspecific competition? ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:463-474. [PMID: 27209788 DOI: 10.1890/14-2365] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Many invasive species experience intense intraspecific competition, because they are abundant in anthropogenically disturbed habitats where few native species persist. Species-specific competitive mechanisms that evolve in this context may offer novel, highly targeted means to control invasive taxa. We conducted laboratory experiments to evaluate the feasibility of this method of control, based on waterborne cues that are produced by tadpoles of the cane toad (Rhinella marina) to suppress the development of conspecific embryos. Our trials examined the nature and species-specificity of the effect, the robustness of the cue to freezing and storage, and the amounts required to suppress toad embryos. Our results were encouraging. The cue appears to be chemical rather than a biological organism, and may well be species-specific; the four species of native anurans that we tested were not influenced by toad larval cues. The cue retains its effectiveness after being frozen, but not after being dried, or after 7 d in water. It is effective at very low concentrations (the amount produced by three tadpoles within 750 L of water). Overall, the cane toad's suppressor pheromone may offer an effective new way to control invasive toads.
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Bournez L, Cangi N, Lancelot R, Pleydell DRJ, Stachurski F, Bouyer J, Martinez D, Lefrançois T, Neves L, Pradel J. Parapatric distribution and sexual competition between two tick species, Amblyomma variegatum and A. hebraeum (Acari, Ixodidae), in Mozambique. Parasit Vectors 2015; 8:504. [PMID: 26438193 PMCID: PMC4595191 DOI: 10.1186/s13071-015-1116-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 09/28/2015] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Amblyomma variegatum and A. hebraeum are two ticks of veterinary and human health importance in south-east Africa. In Zimbabwe they occupy parapatric (marginally overlapping and juxtaposed) distributions. Understanding the mechanisms behind this parapatry is essential for predicting the spatio-temporal dynamics of Amblyomma spp. and the impacts of associated diseases. It has been hypothesized that exclusive competition between these species results from competition at the levels of male signal reception (attraction-aggregation-attachment pheromones) or sexual competition for mates. This hypothesis predicts that the parapatry described in Zimbabwe could also be present in other countries in the region. METHODS To explore this competitive exclusion hypothesis we conducted field surveys at the two species' range limits in Mozambique to identify areas of sympatry (overlapping areas) and to study potential interactions (communicative and reproductive interference effects) in those areas. At sympatric sites, hetero-specific mating pairs were collected and inter-specific attractiveness/repellent effects acting at long and short distances were assessed by analyzing species co-occurrences on co-infested herds and co-infested hosts. RESULTS Co-occurrences of both species at sampling sites were infrequent and localized in areas where both tick and host densities were low. At sympatric sites, high percentages of individuals of both species shared attachment sites on hosts and inter-specific mating rates were high. Although cross-mating rates were not significantly different for A. variegatum and A. hebraeum females, attraction towards hetero-specific males was greater for A. hebraeum females than for A. variegatum females and we observed small asymmetrical repellent effects between males at attachment sites. CONCLUSIONS Our observations suggest near-symmetrical reproductive interference between A. variegatum and A. hebraeum, despite between-species differences in the strength of reproductive isolation barriers acting at the aggregation, fixation and partner contact levels. Theoretical models predict that sexual competition coupled with hybrid inviability, greatly reduces the probability of one species becoming established in an otherwise suitable location when the other species is already established. This mechanism can explain why the parapatric boundary in Mozambique has formed within an area of low tick densities and relatively infrequent host-mediated dispersal events.
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Affiliation(s)
- L Bournez
- CIRAD, UMR CMAEE, F-97170, Petit-Bourg, Guadeloupe, France.
- INRA, UMR 1309 CMAEE, F-34398, Montpellier, France.
- Université des Antilles et de la Guyane, F-97159 Pointe-à-Pitre, Guadeloupe, France.
| | - N Cangi
- CIRAD, UMR CMAEE, F-97170, Petit-Bourg, Guadeloupe, France.
- INRA, UMR 1309 CMAEE, F-34398, Montpellier, France.
- Université des Antilles et de la Guyane, F-97159 Pointe-à-Pitre, Guadeloupe, France.
- Centro de Biotecnologia- Eduardo Mondlane University, Av. de Moçambique, km 1,5, C.P. 257, Maputo, Mozambique.
| | - R Lancelot
- INRA, UMR 1309 CMAEE, F-34398, Montpellier, France.
- CIRAD, UMR CMAEE, F-34398, Montpellier, France.
| | - D R J Pleydell
- CIRAD, UMR CMAEE, F-97170, Petit-Bourg, Guadeloupe, France.
- INRA, UMR 1309 CMAEE, F-34398, Montpellier, France.
| | - F Stachurski
- INRA, UMR 1309 CMAEE, F-34398, Montpellier, France.
- CIRAD, UMR CMAEE, F-34398, Montpellier, France.
| | - J Bouyer
- INRA, UMR 1309 CMAEE, F-34398, Montpellier, France.
- CIRAD, UMR CMAEE, F-34398, Montpellier, France.
- Institut Sénégalais de Recherches Agricoles, Laboratoire National d'Elevage et de Recherches Vétérinaires, BP 2057, Dakar - Hann, Senegal.
| | - D Martinez
- CIRAD, F-97130, Capesterre-Belle-Eau, Guadeloupe, France.
| | - T Lefrançois
- INRA, UMR 1309 CMAEE, F-34398, Montpellier, France.
- CIRAD, UMR CMAEE, F-34398, Montpellier, France.
| | - L Neves
- Centro de Biotecnologia- Eduardo Mondlane University, Av. de Moçambique, km 1,5, C.P. 257, Maputo, Mozambique.
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag x04, Onderstepoort, 0110, South Africa.
| | - J Pradel
- CIRAD, UMR CMAEE, F-97170, Petit-Bourg, Guadeloupe, France.
- INRA, UMR 1309 CMAEE, F-34398, Montpellier, France.
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Syed Z. Chemical ecology and olfaction in arthropod vectors of diseases. CURRENT OPINION IN INSECT SCIENCE 2015; 10:83-89. [PMID: 29588018 DOI: 10.1016/j.cois.2015.04.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 04/17/2015] [Accepted: 04/17/2015] [Indexed: 06/08/2023]
Abstract
Hematophagous arthropods (ticks and insects, collectively hereafter referred to as vectors) transmit various life threatening diseases resulting in over one million human deaths annually. Exploiting vertebrates for blood demanded extensive sensory and behavioral adaptations that are apparent across the evolutionary range of vector species, from primitive ticks to advanced dipterans. Since animal senses are biological features that have been shaped by natural selection to promote adaptive behavior, a variety of exciting patterns are apparent in what they sense and how. Vectors display robust olfactory driven behaviors. A distinct yet limited range of volatile organic compounds are parsimoniously used as major cues for tracking in various contexts. These chemicals elicit behaviors such as attraction or repulsion/avoidance while vectors seek habitats, hosts, mates, or oviposition sites. Interestingly, there is a substantial consilience among olfactory structures and function in arthropod vectors, which is also reflected in the parsimonious use of chemical ligands. A detailed analysis of chemosensory signals and reception by these arthropod vectors can be exploited to identify natural ligands that can be used as baits to manipulate vector behaviors.
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Affiliation(s)
- Zainulabeuddin Syed
- Department of Biological Sciences and Eck Institute for Global Health, Galvin Life Sciences Center, University of Notre Dame, IN 46556, USA.
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Dhivya B, Latha BR, Raja MD, Sreekumar C, Leela V. Control of brown dog tick, Rhipicephalus sanguineus using assembly pheromone encapsulated in natural polymer, chitosan. EXPERIMENTAL & APPLIED ACAROLOGY 2014; 63:85-92. [PMID: 24375150 DOI: 10.1007/s10493-013-9764-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 12/14/2013] [Indexed: 06/03/2023]
Abstract
In the current study, an attempt was made to encapsulate assembly pheromone using natural polymer, chitosan. Chitosan beads were prepared by incorporating assembly pheromone in conjunction with an acaricide, namely, deltamethrin. In the in vitro bioassay, the test beads attracted and killed 79 % of unfed larvae, 88 % of unfed nymphs and 61 % of unfed adults of the brown dog tick, Rhipicephalus sanguineus, in 24 h of exposure. Field trials were carried out to attract and kill the pre-parasitic environmental stages. The beads were dispersed onto specially designed devices and they were placed in infested kennels. The devices were observed after 10 days.
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Affiliation(s)
- Bhoopathy Dhivya
- Department of Veterinary Parasitology, Madras Veterinary College, Vepery, Chennai, 600 007, India,
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Ranju RS, Latha BR, Leela V, Basith SA. Field trials to attract questing stages of brown dog tick, Rhipicephalus sanguineus using tick pheromone-acaricide complex. J Parasit Dis 2014; 37:84-7. [PMID: 24431546 DOI: 10.1007/s12639-012-0136-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2012] [Accepted: 06/13/2012] [Indexed: 12/01/2022] Open
Abstract
Evaluations were made to assess the efficacy of assembly pheromone, attractant sex pheromone and the kairomone carbon dioxide in attracting the questing larval nymphal and adult stages of the brown ear dog tick, Rhipicephalus sanguineus. Ticks attracted to one location were killed using the acaricide deltamethrin. Initially, simulated field trials were conducted to observe the percentage of attraction of ticks from different distances. Tick lure comprising of carbon dioxide as kairomone and 2,6-dichlorophenol in combination with assembly pheromone and deltamethrin on a thermocol platform was prepared and field trials were conducted in the kennels of Blue Cross Society of India, Velachery, Chennai. The tick lure attracted larval, nymphal and adult stages of R. sanguineus ticks in and around the kennels. Observations were made after 24 h of placing the tick lure. In simulated field out of the 50 ticks used for each distance trials, positive response was exhibited by a total number of 20 (40 %), 17 (34 %) and 14 (28 %) ticks from 0.5, 1 and 1.5 m, respectively. Field trials conducted revealed considerable attraction of larvae and nymph to the tick lure. Few adult ticks (2-5) were also lured to the pheromone impregnated filter paper disc.
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Affiliation(s)
- R S Ranju
- Department of Veterinary Parasitology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600007 Tamil Nadu India ; No. 11, Pary Street Extension, Choolaimedu, Chennai, 600094 Tamil Nadu India
| | - Bhaskaran Ravi Latha
- Department of Veterinary Parasitology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600007 Tamil Nadu India
| | - V Leela
- Department of Veterinary Physiology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600007 Tamil Nadu India
| | - S Abdul Basith
- Department of Veterinary Parasitology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600007 Tamil Nadu India
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Yadid I, Rudolph J, Hlouchova K, Copley SD. Sequestration of a highly reactive intermediate in an evolving pathway for degradation of pentachlorophenol. Proc Natl Acad Sci U S A 2013; 110:E2182-90. [PMID: 23676275 PMCID: PMC3683723 DOI: 10.1073/pnas.1214052110] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Microbes in contaminated environments often evolve new metabolic pathways for detoxification or degradation of pollutants. In some cases, intermediates in newly evolved pathways are more toxic than the initial compound. The initial step in the degradation of pentachlorophenol by Sphingobium chlorophenolicum generates a particularly reactive intermediate; tetrachlorobenzoquinone (TCBQ) is a potent alkylating agent that reacts with cellular thiols at a diffusion-controlled rate. TCBQ reductase (PcpD), an FMN- and NADH-dependent reductase, catalyzes the reduction of TCBQ to tetrachlorohydroquinone. In the presence of PcpD, TCBQ formed by pentachlorophenol hydroxylase (PcpB) is sequestered until it is reduced to the less toxic tetrachlorohydroquinone, protecting the bacterium from the toxic effects of TCBQ and maintaining flux through the pathway. The toxicity of TCBQ may have exerted selective pressure to maintain slow turnover of PcpB (0.02 s(-1)) so that a transient interaction between PcpB and PcpD can occur before TCBQ is released from the active site of PcpB.
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Affiliation(s)
| | | | | | - Shelley D. Copley
- Department of Molecular, Cellular and Developmental Biology and Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
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Yoder JA, Jajack AJ, Hedges BZ, Benoit JB. Off-host aggregation in the non-fed, female brown dog tick, Rhipicephalus sanguineus (Latreille), is induced by tick excreta and enhanced by low relative humidity. MEDICAL AND VETERINARY ENTOMOLOGY 2013; 27:209-215. [PMID: 22928633 DOI: 10.1111/j.1365-2915.2012.01040.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report that Rhipicephalus sanguineus (Ixodida: Ixodidae) faeces and its main component, guanine, act as assembly pheromones in short-range Petri plate bioassays. Arrestment activity in response to guanine was lower than that in response to natural excreta, indicating the presence of other active ingredients in natural excreta. The selective removal of appendages was used to establish the important roles played by the palps and the front pair of legs in the detection of the pheromone. Reaction to chemically pure guanine at varying concentrations occurred without a dose response; thus only the presence of guanine, not a critical amount, is required to induce assembly. Higher speed and intensity of clustering occurred at 33% relative humidity (RH). We conclude that female adults of R. sanguineus are more prone to assemble under dry conditions that match the arid microhabitats preferred by this species and that this tendency allows this tick to reside in human dwellings and dog kennels that maintain standards of comfort at 30-50% RH. Cleaning or removing tick excreta-covered surfaces on which ticks aggregate from within and around human dwellings may prove useful as a means of interfering with the establishment of off-host clusters of R. sanguineus.
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Affiliation(s)
- J A Yoder
- Department of Biology, Wittenberg University, Springfield, OH, USA.
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Soares SF, Borges LMF. Electrophysiological responses of the olfactory receptors of the tick Amblyomma cajennense (Acari: Ixodidae) to host-related and tick pheromone-related synthetic compounds. Acta Trop 2012; 124:192-8. [PMID: 22925715 DOI: 10.1016/j.actatropica.2012.08.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Revised: 08/07/2012] [Accepted: 08/08/2012] [Indexed: 11/29/2022]
Abstract
In the present study, host-related and tick pheromone-related chemical compounds were tested by means of the tip-recording technique in order to obtain electrophysiological responses in olfactory sensilla of non-fed Amblyomma cajennense ticks. The following chemicals were tested on the multiporose sensilla DI.1, located anterior to Haller's organ, and the sensillum DII.1, in the anterior pit of this organ: isobutyric acid, butyric acid, valeric acid, trans-2-heptenal, heptanal, benzaldehyde, salicylaldehyde, nonanal, m-, o- and p-tolualdehyde, 2-furaldehyde, 3-pentanone, γ-valerolactone and 1-octen-3-ol (which are all vertebrate-associated volatiles); and 2,6-dichlorophenol (2,6-DCP), 2-nitrophenol, methyl salicylate and nonanoic acid (tick pheromone components). These were used at 10(-3)M and 10(-2)M on at least 10 ticks per substance, and the chemicals that were found to be active at these concentrations were then tested as a series from 10(-6)M to 10(-2)M, in decadic steps, on at least 15 ticks per substance. 2,6-DCP was active on both sensilla, with detection thresholds of 10(-6)M on the DI.1 sensillum and 10(-4)M on the DII.1 sensillum. The olfactory neurons of this sensillum also responded to nonanal at the highest concentration used (10(-2)M), while those of DII.1 responded not only to 2.6 DCP but also to 2-nitrophenol (to the same extent as to 2,6-DCP) and to 1-octen-3-ol. These results confirm the importance of 2,6-DCP in the chemical ecology of A. cajennense and indicate other compounds that may interfere with the behavior of this tick and which should be investigated.
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Affiliation(s)
- Sara Fernandes Soares
- Escola de Veterinária e Zootecnia, Universidade Federal de Goiás Campus II, Samambaia, Goiânia, Brazil.
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Tick infestation patterns in free ranging African buffalo (Syncercus caffer): Effects of host innate immunity and niche segregation among tick species. INTERNATIONAL JOURNAL FOR PARASITOLOGY-PARASITES AND WILDLIFE 2012; 2:1-9. [PMID: 24533310 PMCID: PMC3862501 DOI: 10.1016/j.ijppaw.2012.11.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 10/30/2012] [Accepted: 11/01/2012] [Indexed: 11/24/2022]
Abstract
Ticks are of vast importance to livestock health, and contribute to conflicts between wildlife conservation and agricultural interests; but factors driving tick infestation patterns on wild hosts are not well understood. We studied tick infestation patterns on free-ranging African buffalo (Syncercus caffer), asking (i) is there evidence for niche segregation among tick species?; and (ii) how do host characteristics affect variation in tick abundance among hosts? We identified ticks and estimated tick burdens on 134 adult female buffalo from two herds at Kruger National Park, South Africa. To assess niche segregation, we evaluated attachment site preferences and tested for correlations between abundances of different tick species. To investigate which host factors may drive variability in tick abundance, we measured age, body condition, reproductive and immune status in all hosts, and examined their effects on tick burdens. Two tick species were abundant on buffalo, Amblyomma hebraeum and Rhipicephalus evertsi evertsi. A. hebraeum were found primarily in the inguinal and axillary regions; R. e. evertsi attached exclusively in the perianal area. Abundances of A. hebraeum and R. e. evertsi on the host were unrelated. These results suggest spatial niche segregation between A. hebraeum and R. e. evertsi on the buffalo. Buffalo with stronger innate immunity, and younger buffalo, had fewer ticks. Buffalo with low body condition scores, and pregnant buffalo, had higher tick burdens, but these effects varied between the two herds we sampled. This study is one of the first to link ectoparasite abundance patterns and immunity in a free-ranging mammalian host population. Based on independent abundances of A. hebraeum and R. e. evertsi on individual buffalo, we would expect no association between the diseases these ticks transmit. Longitudinal studies linking environmental variability with host immunity are needed to understand tick infestation patterns and the dynamics of tick-borne diseases in wildlife.
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