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Attir B, Mammeri A, Kechroud N, Mazouz K, Chabira D, Chenchouni H. A survey of nematodes in the European hake ( Merluccius merluccius) intended for human consumption. J Parasit Dis 2024; 48:347-357. [PMID: 38840878 PMCID: PMC11147965 DOI: 10.1007/s12639-024-01674-2] [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: 12/19/2023] [Accepted: 04/15/2024] [Indexed: 06/07/2024] Open
Abstract
Ensuring the safety of fish for human consumption is paramount in safeguarding public health, particularly in relation to parasitic infections. The European hake (Merluccius merluccius Linnaeus, 1758) may harbor various parasitic nematodes, some of which have zoonotic potential. This cross-sectional survey analyzed a random sample of European hake collected from two fish shops in Batna city (NE Algeria). After 24 h in cold storage, the samples were transported to the laboratory for further examination. Fish autopsies revealed a staggering 70% parasitization rate. Microscopic examination of isolated nematodes, treated with glycerine, identified two genera within the Anisakidae family: Anisakis sp. (62%) and Pseudoterranova sp. (31.25%). Unidentified nematodes accounted for 6.75%. The detection of Anisakidae family nematodes in fish intended for human consumption underscores the urgency of rigorous veterinary control. This imperative measure aims to preserve public health, mitigate economic losses, and curtail the environmental consequences associated with the proliferation of such parasites.
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Affiliation(s)
- Badreddine Attir
- Department of Nature and Life Sciences, University of Biskra, 07000 El Hadjeb, Biskra Algeria
- Laboratory of Genetics, Biotechnology, and Valorization of Bioresources (LGBVB), University of Biskra, 07000 Biskra, Algeria
| | - Adel Mammeri
- Laboratory of Genetics, Biotechnology, and Valorization of Bioresources (LGBVB), University of Biskra, 07000 Biskra, Algeria
- Department of Agronomic Sciences, Faculty of Sciences, University of M’Sila, 28000 M’Sila, Algeria
| | - Nassima Kechroud
- Department of Nature and Life Sciences, University of Biskra, 07000 El Hadjeb, Biskra Algeria
| | - Khawla Mazouz
- Department of Nature and Life Sciences, University of Biskra, 07000 El Hadjeb, Biskra Algeria
| | - Djouhaina Chabira
- Department of Nature and Life Sciences, University of Biskra, 07000 El Hadjeb, Biskra Algeria
- Laboratory of Genetics, Biotechnology, and Valorization of Bioresources (LGBVB), University of Biskra, 07000 Biskra, Algeria
| | - Haroun Chenchouni
- Laboratory of Algerian Forests and Climate Change (LAFCC), Higher National School of Forests, 40000 Khenchela, Algeria
- Laboratory of Natural Resources and Management of Sensitive Environments (RNAMS), University of Oum-El-Bouaghi, 04000 Oum-El-Bouaghi, Algeria
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2
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de Oliveira CR, Gonçalves-Sousa JG, de Carvalho EFF, Ávila RW, Borges-Nojosa DM. Effect of altitude and spatial heterogeneity on the host-parasite relationship in anurans from a remnant humid forest in the brazilian semiarid. Parasitol Res 2023; 122:2651-2666. [PMID: 37707610 DOI: 10.1007/s00436-023-07965-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 09/02/2023] [Indexed: 09/15/2023]
Abstract
In the present study, we investigated the effect of habitat heterogeneity, elevation gradient, and phylogenetic distance of host species on the abundance and richness of anuran endoparasites, assuming that parasites follow the distribution of their hosts independently of environmental variation. We collected 192 anurans distributed in three altitude ranges: 100-200 m, 400-500 m, and 700-800 m. We performed discriminant principal component analysis to analyze the interrelationships between environmental heterogeneity and the distribution of parasite and host species in the formation of species groups in each altitude range. We estimated the niche width and parasite overlap, using host species as a variable, and assessed whether parasite abundance is more influenced by historical (distance host phylogeny) or ecological effects in each altitude category and overall. Finally, we use network analyses to understand how interactions between parasites and hosts are formed along the altitude gradient. We found 22 parasite species, and the overall prevalence of infection was 74%. In our study, we did not identify environmental (altitude gradients and heterogeneity) or phylogenetic effects acting on the parasite species diversity. Overall, our results suggest that the parasites are distributed following the dispersal of their hosts and are dispersed among most anuran species.
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Affiliation(s)
- Cicero Ricardo de Oliveira
- Graduate Program in Ecology and Natural Resources, Federal University of Ceará, Block 902, Science Center, PICI Campus, Ceará, Brazil.
- Regional Ophiology Center, Federal University of Ceará, Block 905, Science Center, PICI Campus, Ceará, Brazil.
| | - José Guilherme Gonçalves-Sousa
- Regional Ophiology Center, Federal University of Ceará, Block 905, Science Center, PICI Campus, Ceará, Brazil
- Laboratory of Biology and Ecology of Wild Animals, Federal University of Cariri, Educators Training Institute, Ceará, Brazil
| | - Elvis Franklin Fernandes de Carvalho
- Graduate Program in Ecology and Natural Resources, Federal University of Ceará, Block 902, Science Center, PICI Campus, Ceará, Brazil
- Regional Ophiology Center, Federal University of Ceará, Block 905, Science Center, PICI Campus, Ceará, Brazil
| | - Robson Waldemar Ávila
- Graduate Program in Ecology and Natural Resources, Federal University of Ceará, Block 902, Science Center, PICI Campus, Ceará, Brazil
- Regional Ophiology Center, Federal University of Ceará, Block 905, Science Center, PICI Campus, Ceará, Brazil
| | - Diva Maria Borges-Nojosa
- Graduate Program in Ecology and Natural Resources, Federal University of Ceará, Block 902, Science Center, PICI Campus, Ceará, Brazil
- Regional Ophiology Center, Federal University of Ceará, Block 905, Science Center, PICI Campus, Ceará, Brazil
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3
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Jackson JA, Bajer A, Behnke-Borowczyk J, Gilbert FS, Grzybek M, Alsarraf M, Behnke JM. Remotely sensed localised primary production anomalies predict the burden and community structure of infection in long-term rodent datasets. GLOBAL CHANGE BIOLOGY 2023; 29:5568-5581. [PMID: 37548403 DOI: 10.1111/gcb.16898] [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: 04/12/2023] [Revised: 06/08/2023] [Accepted: 07/06/2023] [Indexed: 08/08/2023]
Abstract
The increasing frequency and cost of zoonotic disease emergence due to global change have led to calls for the primary surveillance of wildlife. This should be facilitated by the ready availability of remotely sensed environmental data, given the importance of the environment in determining infectious disease dynamics. However, there has been little evaluation of the temporal predictiveness of remotely sensed environmental data for infection reservoirs in vertebrate hosts due to a deficit of corresponding high-quality long-term infection datasets. Here we employ two unique decade-spanning datasets for assemblages of infectious agents, including zoonotic agents, in rodents in stable habitats. Such stable habitats are important, as they provide the baseline sets of pathogens for the interactions within degrading habitats that have been identified as hotspots for zoonotic emergence. We focus on the enhanced vegetation index (EVI), a measure of vegetation greening that equates to primary productivity, reasoning that this would modulate infectious agent populations via trophic cascades determining host population density or immunocompetence. We found that EVI, in analyses with data standardised by site, inversely predicted more than one-third of the variation in an index of infectious agent total abundance. Moreover, in bipartite host occupancy networks, weighted network statistics (connectance and modularity) were linked to total abundance and were also predicted by EVI. Infectious agent abundance and, perhaps, community structure are likely to influence infection risk and, in turn, the probability of transboundary emergence. Thus, the present results, which were consistent in disparate forest and desert systems, provide proof-of-principle that within-site fluctuations in satellite-derived greenness indices can furnish useful forecasting that could focus primary surveillance. In relation to the well-documented global greening trend of recent decades, the present results predict declining infection burden in wild vertebrates in stable habitats; but if greening trends were to be reversed, this might magnify the already upwards trend in zoonotic emergence.
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Affiliation(s)
- Joseph A Jackson
- School of Science, Engineering and Environment, University of Salford, Manchester, UK
| | - Anna Bajer
- Department of Eco-Epidemiology of Parasitic Diseases, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Jolanta Behnke-Borowczyk
- Department of Forest Pathology, Faculty of Forestry, Poznań University of Life Sciences, Poznań, Poland
| | - Francis S Gilbert
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK
| | - Maciej Grzybek
- Department of Tropical Parasitology, Institute of Maritime and Tropical Medicine, Medical University of Gdansk, Gdynia, Poland
| | - Mohammed Alsarraf
- Department of Eco-Epidemiology of Parasitic Diseases, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Jerzy M Behnke
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK
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4
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Morgan ER, Segonds-Pichon A, Ferté H, Duncan P, Cabaret J. Anthelmintic Treatment and the Stability of Parasite Distribution in Ruminants. Animals (Basel) 2023; 13:1882. [PMID: 37889834 PMCID: PMC10251989 DOI: 10.3390/ani13111882] [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: 04/18/2023] [Revised: 05/26/2023] [Accepted: 05/29/2023] [Indexed: 10/29/2023] Open
Abstract
Parasites are generally overdispersed among their hosts, with far-reaching implications for their population dynamics and control. The factors determining parasite overdispersion have long been debated. In particular, stochastic parasite acquisition and individual host variation in density-dependent regulation through acquired host immunity have been identified as key factors, but their relative roles and possible interactions have seen little empirical exploration in parasite populations. Here, Taylor's power law is applied to test the hypothesis that periodic parasite removal destabilises the host-parasite relationship and increases variance in parasite burden around the mean. The slope of the power relationship was compared by analysis of covariance among 325 nematode populations in wild and domestic ruminants, exploiting that domestic ruminants are often routinely treated against parasite infections. In Haemonchus spp. and Trichostrongylus axei in domestic livestock, the slope increased with the frequency of anthelmintic treatment, supporting this hypothesis. In Nematodirus spp., against which acquired immunity is known to be strong, the slope was significantly greater in post-mortem worm burden data than in faecal egg counts, while this relationship did not hold for the less immunogenic genus Marshallagia. Considered together, these findings suggest that immunity acting through an exposure-dependent reduction in parasite fecundity stabilises variance in faecal egg counts, reducing overdispersion, and that periodic anthelmintic treatment interferes with this process and increases overdispersion. The results have implications for the diagnosis and control of parasitic infections in domestic animals, which are complicated by overdispersion, and for our understanding of parasite distribution in free-living wildlife. Parasite-host systems, in which treatment and immunity effectively mimic metapopulation processes of patch extinction and density dependence, could also yield general insights into the spatio-temporal stability of animal distributions.
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Affiliation(s)
- Eric R. Morgan
- School of Biological Sciences, Queen’s University Belfast, 19, Chlorine Gardens, Belfast BT9 5DL, UK
| | | | - Hubert Ferté
- Faculté de Pharmacie, Université de Reims Champagne-Ardenne, SFR Cap Santé, EA7510 ESCAPE–USC VECPAR, 51 rue Cognacq-Jay, 51096 Reims, France;
| | - Patrick Duncan
- Centre d’Etudes Biologiques de Chize, CNRS UPR 1934, 79360 Beauvoir-sur-Niort, France;
| | - Jacques Cabaret
- ISP, INRAE, Université Tours, UMR1282, 37380 Nouzilly, France;
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Jithila PJ, Abaunza P, Prasadan PK. Distribution of different species of metacercariae in two freshwater fishes: Haludaria fasciata (Teleostei: Cyprinidae) and Pseudosphromenus cupanus (Teleostei: Osphromenidae). J Parasit Dis 2022; 46:113-123. [PMID: 35299924 PMCID: PMC8901812 DOI: 10.1007/s12639-021-01421-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 07/18/2021] [Indexed: 11/29/2022] Open
Abstract
Information on the distribution and abundance patterns of trematodes are essential to reveal the ecology of host-parasite interactions. The Western Ghats of India, a biodiversity hotspot, is rich in freshwater fish diversity and endemism. Though there are several studies on various other aspects of fish ecology, studies on their parasitic fauna is meager. The objective of the present study is to explore the distribution and infection patterns of metacercariae of five species of trematodes in the freshwater fishes, Haludaria fasciata and Pseudosphromenus cupanus. The infection parameters were analyzed for each host and CART model was applied to analyze the environmental factors affecting parasite distribution patterns. All species of metacercariae showed an over-dispersed aggregate distributions. The classification tree models indicated that among the environmental factors considered, differences in host locality was the most influential factor in both fishes, followed at a greater distance by the factor seasonality. The parasite communities exhibited temporal and spatial differences in the infection pattern in response to seasonal and locational variations.
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Affiliation(s)
- P. J. Jithila
- Ecological Parasitology and Tropical Biodiversity Laboratory, Department of Zoology, Kannur University, Mananthavady Campus, Wayanad, Kerala 670645 India
| | - P. Abaunza
- Instituto Español de Oceanografía (IEO), C.O. de Santander, Promontorio San Martín s/n, 39004 Santander, Cantabria Spain
| | - P. K. Prasadan
- Ecological Parasitology and Tropical Biodiversity Laboratory, Department of Zoology, Kannur University, Mananthavady Campus, Wayanad, Kerala 670645 India
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6
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Mushagalusa Mulega A, Muterezi Bukinga F, Akoumba JF, Mulungula PM, Pariselle A. Monogeneans from Catfishes in Lake Tanganyika. I: Two new species of Bagrobdella (Dactylogyridae) from Auchenoglanis occidentalis (Siluriformes: Claroteidae). ZOOLOGIA 2022. [DOI: 10.1590/s1984-4689.v39.e22016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Archimède Mushagalusa Mulega
- Mohammed V University, Morocco; Centre de Recherche en Hydrobiologie, Democratic Republic of the Congo; Hasselt University, Belgium
| | | | | | - Pascal Masilya Mulungula
- Centre de Recherche en Hydrobiologie, Democratic Republic of the Congo; Institut Supérieur Pédagogique de Bukavu, Democratic Republic of the Congo
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7
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Experimental evidence that host choice by parasites is age-dependent in a fish-monogenean system. Parasitol Res 2021; 121:115-126. [PMID: 34755222 DOI: 10.1007/s00436-021-07356-9] [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: 08/14/2021] [Accepted: 10/19/2021] [Indexed: 10/19/2022]
Abstract
Host age is known to influence the risk of parasite infection, but there is very little experimental evidence on whether parasites show preference towards potential hosts of a specific age. To investigate how host age affects host choice by parasites, we used the Nile tilapia (Oreochromis niloticus) as a fish parasite model and manipulated its gill ectoparasitic monogeneans in mesocosm experiments. Our experimental setting combined three age classes (juvenile, subadult, and adult) of both infected donor hosts and uninfected potential target hosts assigned to each treatment. We predicted that adult target hosts would be more susceptible to parasites than juveniles and adults because they represent high-quality habitat patches. Contrary to our prediction, we found that subadults were more susceptible to parasites than juvenile and adult target hosts. Our models confirmed that variation in target host age influenced parasite choice, suggesting that subadults might represent the most favourable option for parasites regarding a balance between host quality and susceptibility. We provide experimental evidence that host choice by parasites is age-dependent, and that this life-history trait can play a major role in structuring parasite populations.
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8
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Neal T, Kent ML, Sanders J, Schreck CB, Peterson JT. Laboratory infection rates and associated mortality of juvenile Chinook Salmon (Oncorhynchus tshawytscha) from parasitic copepod (Salmincola californiensis). JOURNAL OF FISH DISEASES 2021; 44:1423-1434. [PMID: 34053103 DOI: 10.1111/jfd.13450] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/04/2021] [Accepted: 05/06/2021] [Indexed: 06/12/2023]
Abstract
Pacific salmon (Oncorhynchus spp.) rearing in lakes and reservoirs above dams have been known to become heavily infected with an ectoparasitic copepod (Salmincola californiensis). Little is known about the factors that affect the parasite infection prevalence and intensity. However, previous research suggests that the parasite may negatively affect the fitness and survival of the host fish. The effect of water temperature, confinement and the density of the free-swimming infectious stage of S. californiensis, the copepodid, on infection prevalence and intensity was evaluated by experimentally exposing juvenile Chinook Salmon (O. tshawytscha). Infection rates observed in wild populations were achieved under warm water (15-16°C) and high copepodid density (150-300/L) treatment conditions. Infection prevalence and intensity were also significantly higher in larger fish. During the infection experiment, 4.5% of infected fish died within 54 days with mortality significantly related to copepod infection intensity. The potential for autoinfection was compared to cross-infection by cohabitation of infected fish with naïve fish. Previously infected fish had significantly greater infection intensity compared with naïve fish, indicating that infected fish can be reinfected and that they may be more susceptible than naïve fish.
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Affiliation(s)
- Travis Neal
- Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, USA
| | - Michael L Kent
- Department of Microbiology, Oregon State University, Corvallis, OR, USA
- Department of Biomedical Sciences, Oregon State University, Corvallis, OR, USA
| | - Justin Sanders
- Department of Biomedical Sciences, Oregon State University, Corvallis, OR, USA
| | - Carl B Schreck
- Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, USA
| | - James T Peterson
- US Geological Survey, Oregon Cooperative Fish and Wildlife Research Unit, Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, USA
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9
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Helminth communities in amphibians from Latvia, with an emphasis on their connection to host ecology. J Helminthol 2021; 95:e48. [PMID: 34429177 DOI: 10.1017/s0022149x2100047x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Helminth infracommunities were studied at 174 sites of Latvia in seven hosts from six amphibian taxa of different taxonomical, ontogenic and ecological groups. They were described using a standard set of parasitological parameters, compared by ecological indices and linear discriminant analysis. Their species associations were identified by Kendall's rank correlation, but relationships with host size and waterbody area were analysed by zero-inflated Poisson and zero-inflated negative binomial regressions. The richest communities (25 species) were found in post-metamorphic semi-aquatic Pelophylax spp. frogs, which were dominated by trematode species of both adult and larval stages. Both larval and terrestrial hosts yielded depauperate trematode communities with accession of aquatic and soil-transmitted nematode species, respectively. Nematode loads peaked in terrestrial Bufo bufo. Helminth infracommunities suggested some differences in host microhabitat or food object selection not detected by their ecology studies. Associations were present in 96% of helminth species (on average, 7.3 associations per species) and dominated positive ones. Species richness and abundances, in most cases, were positively correlated with host size, which could be explained by increasing parasite intake rates over host ontogeny (trematode adult stages) or parasite accumulation (larval Alaria alata). Two larval diplostomid species (Strigea strigis, Tylodelphys excavata) had a negative relationship with host size, which could be caused by parasite-induced host mortality. The adult trematode abundances were higher in larger waterbodies, most likely due to their ecosystem richness, while higher larval abundances in smaller waterbodies could be caused by elevated infection rates under high host densities.
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10
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Jackson JA, Friberg IM, Hablützel PI, Masud N, Stewart A, Synnott R, Cable J. Partitioning the environmental drivers of immunocompetence. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 747:141152. [PMID: 32799018 DOI: 10.1016/j.scitotenv.2020.141152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 07/08/2020] [Accepted: 07/19/2020] [Indexed: 06/11/2023]
Abstract
By determining susceptibility to disease, environment-driven variation in immune responses can affect the health, productivity and fitness of vertebrates. Yet how the different components of the total environment control this immune variation is remarkably poorly understood. Here, through combining field observation, experimentation and modelling, we are able to quantitatively partition the key environmental drivers of constitutive immune allocation in a model wild vertebrate (three-spined stickleback, Gasterosteus aculeatus). We demonstrate that, in natural populations, thermal conditions and diet alone are sufficient (and necessary) to explain a dominant (seasonal) axis of variation in immune allocation. This dominant axis contributes to both infection resistance and tolerance and, in turn, to the vital rates of infectious agents and the progression of the disease they cause. Our results illuminate the environmental regulation of vertebrate immunity (given the evolutionary conservation of the molecular pathways involved) and they identify mechanisms through which immunocompetence and host-parasite dynamics might be impacted by changing environments. In particular, we predict a dominant sensitivity of immunocompetence and immunocompetence-driven host-pathogen dynamics to host diet shifts.
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Affiliation(s)
- Joseph A Jackson
- Ecoimmunology Laboratory, School of Science, Engineering and Environment, University of Salford, Manchester, UK.
| | - Ida M Friberg
- Ecoimmunology Laboratory, School of Science, Engineering and Environment, University of Salford, Manchester, UK
| | - Pascal I Hablützel
- IBERS, Aberystwyth University, Aberystwyth, UK; Flanders Marine Institute, Oostende, Belgium; Laboratory of Biodiversity and Evolutionary Genomics, Biology Department, University of Leuven, Leuven, Belgium
| | - Numair Masud
- School of Biosciences, Cardiff University, Cardiff, UK
| | | | - Rebecca Synnott
- Ecoimmunology Laboratory, School of Science, Engineering and Environment, University of Salford, Manchester, UK
| | - Joanne Cable
- School of Biosciences, Cardiff University, Cardiff, UK
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11
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Timi JT, Poulin R. Why ignoring parasites in fish ecology is a mistake. Int J Parasitol 2020; 50:755-761. [PMID: 32592807 DOI: 10.1016/j.ijpara.2020.04.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/08/2020] [Accepted: 04/18/2020] [Indexed: 12/14/2022]
Abstract
Parasites are ubiquitous components of biological systems that have evolved in multiple independent lineages during the history of life, resulting in a diversity of taxa greater than that of their free-living counterparts. Extant host-parasite associations are the result of tight reciprocal adaptations that allow parasites to exploit specific biological features of their hosts to ensure their transmission, survival, and maintenance of viable populations. As a result, parasites may affect host physiology, morphology, reproduction or behaviour, and they are increasingly recognized as having significant impacts on host individuals, populations, communities and even ecosystems. Although this is usually acknowledged by parasite ecologists, fish ecologists often ignore parasitism in their studies, often acting as though their systems are free of parasites. However, the effects of parasites on their hosts can alter variables routinely used in fish ecology, ranging from the level of individual fish (e.g. condition factors) to populations (e.g. estimates of mortality and reproductive success) or communities (e.g. measures of interspecific competition or the structure and functioning of food webs). By affecting fish physiology, parasites can also interfere with measurements of trophic levels by means of stable isotope composition, or have antagonistic or synergistic effects with host parameters normally used as indicators of different sources of pollution. Changes in host behaviour induced by parasites can also modify host distribution patterns, habitat selection, diet composition, sexual behaviour, etc., with implications for the ecology of fish and of their predators and prey. In this review, we summarise and illustrate the likely biases and erroneous conclusions that one may expect from studies of fish ecology that ignore parasites, from the individual to the community level. Given the impact of parasites across all levels of biological organisation, we show that their omission from the design and analyses of ecological studies poses real risks of flawed interpretations for those patterns and processes that ecologists seek to uncover.
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Affiliation(s)
- Juan T Timi
- Laboratorio de Ictioparasitología, Instituto de Investigaciones Marinas y Costeras (IIMyC), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Funes 3350, (7600) Mar del Plata, Argentina.
| | - Robert Poulin
- Zoology Department, University of Otago, PO Box 56, Dunedin 9054, New Zealand
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12
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Fecchio A, Martins TF, Bell JA, De La Torre GM, Pinho JB, Weckstein JD, Tkach VV, Labruna MB, Dias RI. Low host specificity and lack of parasite avoidance by immature ticks in Brazilian birds. Parasitol Res 2020; 119:2039-2045. [PMID: 32377908 DOI: 10.1007/s00436-020-06698-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 04/21/2020] [Indexed: 11/28/2022]
Abstract
Ticks are ectoparasites that feed on blood of a broad taxonomic range of terrestrial and flying vertebrates and are distributed across a wide range of environmental conditions. Here, we explore the biotic and abiotic factors on infestation probability of ticks of the genus Amblyomma and assess the degree of host specificity based on analysis of 1028 birds surveyed across Brazil. We show that tick infestation rates exhibited considerable variation across the 235 avian species analyzed and that the probability of an individual bird being parasitized by immature ticks (larvae and nymphs) increased with annual precipitation. Host phylogeny and two host ecological traits known to promote tick exposure (body mass and foraging behavior) did not predict infestation probability. Moreover, immature ticks displayed a low degree of host specificity at the family level. Lastly, tick occurrence in birds carrying infection with avian malaria and related parasites did not differ from those free of these haemosporidian parasites, indicating a lack of parasite avoidance by immature ticks. Our findings demonstrate that tick occurrence in birds across Brazilian biomes responds to environmental factors rather than ecological and evolutionary host attributes.
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Affiliation(s)
- Alan Fecchio
- Programa de Pós-graduação em Ecologia e Conservação da Biodiversidade, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil.
| | - Thiago F Martins
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Jeffrey A Bell
- Department of Biology, University of North Dakota, Grand Forks, ND, 58202, USA
| | - Gabriel M De La Torre
- Programa de Pós-graduação em Ecologia e Conservação, Laboratório de Ecologia e Interações Antagonísticas, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - João B Pinho
- Programa de Pós-graduação em Ecologia e Conservação da Biodiversidade, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil.,Laboratório de Ecologia de Aves, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil
| | - Jason D Weckstein
- Department of Ornithology, Academy of Natural Sciences of Drexel University, Philadelphia, PA, 19103, USA.,Department of Biodiversity, Earth, and Environmental Science, Drexel University, Philadelphia, PA, 19103, USA
| | - Vasyl V Tkach
- Department of Biology, University of North Dakota, Grand Forks, ND, 58202, USA
| | - Marcelo B Labruna
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Raphael I Dias
- Faculdade de Ciências da Educação e Saúde, Centro Universitário de Brasília, Brasília, DF, Brazil.,Programa de Pós-graduação em Zoologia, Universidade de Brasília, Brasília, DF, Brazil
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Tierney PA, Caffrey JM, Vogel S, Matthews SM, Costantini E, Holland CV. Invasive freshwater fish (Leuciscus leuciscus) acts as a sink for a parasite of native brown trout Salmo trutta. Biol Invasions 2020. [DOI: 10.1007/s10530-020-02253-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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