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Sağlam YS, Yildirim S, Özkaraca M, Altun S. Investigation of leptospiral antigen with immunohistochemical and immunofluorescence methods in cattle kidney. Microb Pathog 2022; 164:105434. [DOI: 10.1016/j.micpath.2022.105434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/28/2022] [Accepted: 01/30/2022] [Indexed: 11/15/2022]
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Fávero JF, de Araújo HL, Lilenbaum W, Machado G, Tonin AA, Baldissera MD, Stefani LM, Da Silva AS. Bovine leptospirosis: Prevalence, associated risk factors for infection and their cause-effect relation. Microb Pathog 2017; 107:149-154. [PMID: 28351712 DOI: 10.1016/j.micpath.2017.03.032] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 03/21/2017] [Accepted: 03/24/2017] [Indexed: 11/18/2022]
Abstract
Leptospirosis is a cosmopolitan infectious disease that causes severe reproductive disorders in cattle, especially those related to abortion. This disease has rodents as main reservoirs; however, cattle are responsible for maintenance of the disease. Thus, the aim of this study was to identify the factors associated with infection and cause-effect relation of leptospirosis in dairy herds from Southern of Brazil. Serum samples of 1242 cows were collected from herds classified as of medium and high density, and tested by microscopic agglutination test (MAT). These farms were located in the West part of Santa Catarina State (Brazil). A total of 80 cows (6.44%) were considered positives for the infection with titration of 1:100. Using a multivariate analysis, we identified two factors associated to bovine leptospirosis: dog access to pastures (p < 0.001) and feed exposure to rodents (p = 0.05). Cause-effect analysis demonstrated that the occurrence of reproductive disorders was significantly (p = 0.01) linked to leptospirosis. Thus, we conclude that leptospirosis is prevalent in dairy cattle in the west part of Santa Catarina state, as well as the access of dogs to pastures and contact of rodents with feed increase the chance of cattle infection by Leptospira spp.
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Affiliation(s)
- Juscivete F Fávero
- Graduate Program in Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, Santa Catarina (SC), Brazil; Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, Santa Catarina (SC), Brazil; UNIEDU - FUMDES scholarship, Santa Catarina State (SC), Brazil
| | - Hugo L de Araújo
- Laboratory of Veterinary Bacteriology, Universidade Federal Fluminense (UFF), Niterói, Rio de Janeiro (RJ), Brazil
| | - Walter Lilenbaum
- Laboratory of Veterinary Bacteriology, Universidade Federal Fluminense (UFF), Niterói, Rio de Janeiro (RJ), Brazil
| | - Gustavo Machado
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota (UMN), Saint Paul, Minnesota (MN), USA
| | - Alexandre A Tonin
- Department of Veterinary Medicine, Universidade do Oeste de Santa Catarina (UNOESC), Xanxerê, Santa Catarina (SC), Brazil
| | - Matheus D Baldissera
- Department of Microbiology and Parasitology, Universidade Federal de Santa Maria, RS, Brazil
| | - Lenita M Stefani
- Graduate Program in Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, Santa Catarina (SC), Brazil; Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, Santa Catarina (SC), Brazil
| | - Aleksandro S Da Silva
- Graduate Program in Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, Santa Catarina (SC), Brazil; Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, Santa Catarina (SC), Brazil.
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Arent ZJ, Gilmore C, San-Miguel Ayanz JM, Neyra LQ, García-Peña FJ. Molecular Epidemiology of Leptospira Serogroup Pomona Infections Among Wild and Domestic Animals in Spain. ECOHEALTH 2017; 14:48-57. [PMID: 28213654 DOI: 10.1007/s10393-017-1210-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 01/10/2017] [Accepted: 01/16/2017] [Indexed: 06/06/2023]
Abstract
Strains of Leptospira serogroup Pomona are known to cause widespread animal infections in many parts of the world. Forty-three isolates retrieved from domestic animals and wild small mammals suggest that serogroup Pomona is epidemiologically relevant in Spain. This is supported by the high prevalence of serovar Pomona antibodies in livestock and wild animals. In this study, the strains were serologically and genetically characterized in an attempt to elucidate their epidemiology. Serological typing was based on the microscopic agglutination test but molecular typing involved species-specific polymerase chain reaction, restriction endonuclease analysis, and multiple-locus variable-number tandem repeat analysis. The study revealed that the infections are caused by two serovars, namely Pomona and Mozdok. Serovar Pomona was derived only from farm animals and may be adapted to pigs, which are recognized as the maintenance host. The results demonstrated that serovar Pomona is genetically heterogeneous and three different types were recognized. This heterogeneity was correlated with different geographical distributions of the isolates. All strains derived from small wild mammals were identified as serovar Mozdok. Some isolates of this serovar retrieved from cattle confirm that this serovar may also be the cause of infections in food-producing animals for which these wild species may be source of infection.
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Affiliation(s)
- Z J Arent
- OIE Leptospira Reference Laboratory, Agri-Food and Biosciences Institute, Veterinary Sciences Division, Stoney Road, Stormont, Belfast, BT4 3SD, UK.
- University Centre of Veterinary Medicine JU-AUK, University of Agriculture in Krakow, Al. Mickiewicza 24/28, 30-059, Kraków, Poland.
| | - C Gilmore
- OIE Leptospira Reference Laboratory, Agri-Food and Biosciences Institute, Veterinary Sciences Division, Stoney Road, Stormont, Belfast, BT4 3SD, UK
| | | | - L Quevedo Neyra
- ADS JANDAVET, Calle Paterna, Local 4, 11170, Medina Sidonia (Cádiz), Spain
| | - F J García-Peña
- Bacteriology Department 2, Laboratorio Central de Veterinaria de Algete (MAGRAMA), 28110, Algete, Madrid, Spain
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Mason MR, Encina C, Sreevatsan S, Muñoz-Zanzi C. Distribution and Diversity of Pathogenic Leptospira Species in Peri-domestic Surface Waters from South Central Chile. PLoS Negl Trop Dis 2016; 10:e0004895. [PMID: 27529550 PMCID: PMC4986978 DOI: 10.1371/journal.pntd.0004895] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 07/12/2016] [Indexed: 11/25/2022] Open
Abstract
Background Leptospirosis is a neglected zoonosis affecting animals and humans caused by infection with Leptospira. The bacteria can survive outside of hosts for long periods of time in soil and water. While identification of Leptospira species from human cases and animal reservoirs are increasingly reported, little is known about the diversity of pathogenic Leptospira species in the environment and how surveillance of the environment might be used for monitoring and controlling disease. Methods and Findings Water samples (n = 104) were collected from the peri-domestic environment of 422 households from farms, rural villages, and urban slums participating in a broader study on the eco-epidemiology of leptospirosis in the Los Rios Region, Chile, between October 2010 and April 2012. The secY region of samples, previously detected as pathogenic Leptospira by PCR, was amplified and sequenced. Sequences were aligned using ClustalW in MEGA, and a minimum spanning tree was created in PHYLOViZ using the goeBURST algorithm to assess sequence similarity. Sequences from four clinical isolates, 17 rodents, and 20 reference strains were also included in the analysis. Overall, water samples contained L. interrogans, L. kirschneri, and L. weilii, with descending frequency. All species were found in each community type. The distribution of the species differed by the season in which the water samples were obtained. There was no evidence that community-level prevalence of Leptospira in dogs, rodents, or livestock influenced pathogen diversity in the water samples. Conclusions This study reports the presence of pathogenic Leptospira in the peri-domestic environment of households in three community types and the differences in Leptospira diversity at the community level. Systematic environmental surveillance of Leptospira can be used for detecting changes in pathogen diversity and to identify and monitor contaminated areas where an increased risk of human infection exists. Leptospirosis is a zoonotic disease that is caused by either direct contact with the urine of animals infected with pathogenic forms of Leptospira, or indirectly, through contact with contaminated water or soil. Because many people become infected through the environment, where the bacteria can live for many months if the conditions are suitable, we tested water samples from the peri-domestic area in twelve different communities from Los Rios region, Chile, to examine whether the Leptospira species were different in urban, rural village, and farm areas. We found that all three community types had L. interrogans, L. kirschneri, and L. weilii. No evident associations were seen between animal infection and the frequency or diversity of Leptospira. The proposed surveillance method has potential for systematic monitoring of surface waters that will help us better understand the importance of animal, climate, and environmental factors in the variation of Leptospira species present in a community in order to predict infection risk and inform prevention programs.
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Affiliation(s)
- Meghan R. Mason
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Carolina Encina
- Institute of Preventive Veterinary Medicine, Universidad Austral de Chile, Valdivia, Chile
| | - Srinand Sreevatsan
- College of Veterinary Medicine, University of Minnesota, Saint Paul, Minnesota, United States of America
| | - Claudia Muñoz-Zanzi
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota, United States of America
- Institute of Preventive Veterinary Medicine, Universidad Austral de Chile, Valdivia, Chile
- * E-mail:
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Millán J, García EJ, Oleaga Á, López-Bao JV, Llaneza L, Palacios V, Candela MG, Cevidanes A, Rodríguez A, León-Vizcaíno L. Using a top predator as a sentinel for environmental contamination with pathogenic bacteria: the Iberian wolf and leptospires. Mem Inst Oswaldo Cruz 2014; 109:1041-4. [PMID: 25494467 PMCID: PMC4325608 DOI: 10.1590/0074-0276140258] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 12/19/2014] [Indexed: 11/21/2022] Open
Abstract
The Iberian wolf (Canis lupus) is the top predator in the Iberian
environments in which it lives, feeding on a wide range of species, thus encountering
a wide range of disease agents. Therefore, the wolf can serve as sentinel of
environmental contamination with pathogens. We investigated the exposure of
free-living wolves to 14 serovars of Leptospira interrogans sensu
lato. Kidney samples from 49 wolves collected from 2010-2013 in
northwestern Spain were analysed by culture, direct immunofluorescence and polymerase
chain reaction. Tissue fluids were analysed for antibodies by a microscopic
agglutination test. Ten wolves (observed prevalence: 20%, 95% confidence interval =
11-33%) showed evidence of contact with leptospires, eight through direct detection
and nine through serology (7 wolves were positive according to both techniques).
Titres below the cut-off level were also detected in seven cases. Serovars confirmed
were Canicola (n = 4), Icterohaemorrhagiae (n = 3) and Sejroë, Ballum and
Grippotyphosa (n = 1 each), indicating that wolves were infected with serovars for
which dogs, rodents and ungulates, are the natural hosts and supporting the utility
of the wolf and other large predators as environmental sentinels for pathogens.
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Affiliation(s)
- Javier Millán
- Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Santiago, Chile
| | | | - Álvaro Oleaga
- Sociedad de Servicios del Principado de Asturias SA, Asturias, Spain
| | - José Vicente López-Bao
- Unidad Mixta de Investigación en Biodiversidad, Universidad de Oviedo-Consejo Superior de Investigaciones Científicas-Principado de Asturias, Mieres, Spain
| | | | | | - Mónica G Candela
- Área de Enfermedades Infecciosas, Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de Murcia, Murcia, Spain
| | | | - Alejandro Rodríguez
- Departamento de la Biología de la Conservación, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas, Sevilla, Spain
| | - Luis León-Vizcaíno
- Área de Enfermedades Infecciosas, Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de Murcia, Murcia, Spain
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Benkirane A, Noury S, Hartskeerl RA, Goris MGA, Ahmed A, Nally JE. Preliminary Investigations on the Distribution ofLeptospiraSerovars in Domestic Animals in North-west Morocco. Transbound Emerg Dis 2014; 63:e178-84. [DOI: 10.1111/tbed.12252] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Indexed: 11/29/2022]
Affiliation(s)
- A. Benkirane
- Institut Agronomique et Vétérinaire Hassan II; Rabat Morocco
| | - S. Noury
- Institut Agronomique et Vétérinaire Hassan II; Rabat Morocco
| | | | | | - A. Ahmed
- KIT Biomedical Research; Amsterdam The Netherlands
| | - J. E. Nally
- School of Veterinary Medicine; University College Dublin; Dublin Ireland
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Abstract
A cross-sectional serological survey was conducted during January to August 2001 to determine the seroprevalence of Leptospira serovars in five species of livestock in Thailand and to identify associations between seropositivity and sex, age, species and geographical locations. Sera from 14188 livestock (9288 cattle, 1376 buffaloes, 1898 pigs, 1110 sheep, 516 goats) from 36 provinces were tested for antibodies against 24 Leptospira serovars with the microscopic agglutination test (MAT) for which the criterion for a positive result was set at a titre of ≥1:50. A total of 1635 [11·5%, 95% confidence interval (CI) 11·0-12·0] animals were seropositive and the highest prevalence (30·4%, 95% CI 28·2-32·5) of evidence of infection was recorded in the northeast region followed by the central region (22·2%, 95% CI 20-24·6). Seroprevalences recorded for cattle, buffaloes, pigs, sheep and goats were 9·9% (95% CI 9·3-10·5), 30·5% (95% CI 28·1-32·9), 10·8% (95% CI 9·5-12·3), 4·7% (95% CI 3·6-6·1) and 7·9% (95% CI 5·8-10·5), respectively. Buffaloes were 3·1 (95% CI 2·8-3·4) times more likely than cattle to be seropositive. The most commonly detected antibodies were against L. interrogans serovars Ranarum, Sejroe, and Mini in cattle, Mini, Sejroe, and Bratislava in buffaloes, Ranarum, Pomona, and Bratislava in pigs and Mini, Shermani, and Ranarum in sheep and goats. Seroprevalences in cattle and buffaloes trended upwards with increasing age and there was no difference in the risk of seropositivity between males and females.
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Subharat S, Wilson PR, Heuer C, Collins-Emerson JM. Longitudinal serological survey and herd-level risk factors forLeptospiraspp. serovars Hardjo-bovis and Pomona on deer farms with sheep and/or beef cattle. N Z Vet J 2012; 60:215-22. [DOI: 10.1080/00480169.2012.663323] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Schoonman L, Swai ES. Herd- and animal-level risk factors for bovine leptospirosis in Tanga region of Tanzania. Trop Anim Health Prod 2010; 42:1565-72. [DOI: 10.1007/s11250-010-9607-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2010] [Indexed: 10/19/2022]
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Leptospiral antibodies in Iberian red deer (Cervus elaphus hispanicus), fallow deer (Dama dama) and European wild boar (Sus scrofa) in Asturias, Northern Spain. Vet J 2010; 183:226-7. [DOI: 10.1016/j.tvjl.2008.10.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Revised: 10/03/2008] [Accepted: 10/05/2008] [Indexed: 11/21/2022]
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Millán J, Candela MG, López-Bao JV, Pereira M, Jiménez MA, León-Vizcaíno L. Leptospirosis in wild and domestic carnivores in natural areas in Andalusia, Spain. Vector Borne Zoonotic Dis 2010; 9:549-54. [PMID: 18973450 DOI: 10.1089/vbz.2008.0081] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Leptospirosis is a zoonosis that affects humans, domestic animals, and wildlife. Carnivores are at the top of the feeding chain, thus being exposed to pathogens through their preys. From June 2004 to April 2007, we analyzed for evidences of contact with 14 serovars of Leptospira interrogans Sensu Lato serum (analyzed by indirect Microscopic Agglutination Test) and urine or kidney samples (analyzed by microscopic observation, immunostaining and culture) collected from 201 wild and domestic carnivores, including 26 free-living Iberian lynx (Lynx pardinus), 33 red foxes (Vulpes vulpes), 33 Egyptian mongooses (Herpestes ichneumon), 25 common genets (Genetta genetta), two Eurasian badgers (Meles meles) and one Eurasian otter (Lutra lutra), and 53 free-roaming cats and 28 rural dogs in protected areas in Andalusia (southern Spain). Twenty-three percent of the animals presented evidences of contact, being the prevalence similar among wild (23.5%) and domestic species (22.2%). Contact with Lesptospira was detected in all the species but the otter. Prevalence was: lynx (11% by bacteriological detection, 32% by serology), fox (0%, 47%), mongoose (5%, 20%), genet (0%, 12%), badger (0%, 50%), cat (20%, 14%), dog (only serology: 36%). Serovar Icterohemorragiae accounted for 2/3 of the cases. Serovar Canicola was detected in half of the positive dogs and one lynx. Other serovars detected were Ballum, Sejroë, and Australis. No macroscopic lesions were observed in necropsied animals that showed evidence of contact with the agent, although histopathologic lesions (chiefly chronic interstitial nephritis) were observed in 7 out of the 11 microscopically analyzed individuals. Thus, L. interrogans may cause previously unrecorded disease in wild carnivores in Spain. Wild and free-roaming carnivores may not act as reservoir of L. interrogans but as a dead-end hosts, though the dog may act as reservoir of serovar Canicola. Carnivores are apparently good sentinels for the epidemiological monitorization of leptospirosis.
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Affiliation(s)
- Javier Millán
- Department of Conservation Biology, Estación Biológica de Doñana (CSIC), Pabellón del Perú, Avda. María Luisa s/n, Sevilla, Spain.
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Burriel AR, Dalley C, Woodward MJ. Prevalence of leptospira species among farmed and domestic animals in Greece. Vet Rec 2003; 153:146-8. [PMID: 12934797 DOI: 10.1136/vr.153.5.146] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
A total of 1527 serum samples from pigs, goats, sheep, cattle and dogs in Greece were examined by the microscopic agglutination test and 11-8 per cent of them had antibodies against one or more Leptospira serovars at titres of 1/100 or more. The predominant serovar affecting farm animal species was Bratislava, and Copenhageni was common among dogs and the second most important serovar when all animals were considered together. Another prevalent serovar was Australis, but antibodies to Pomona were detected only in goats and cattle.
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Affiliation(s)
- A R Burriel
- Faculty of Veterinary Medicine, University of Thessaly, Karditsa 43100, Box 199, Greece
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Alonso-Andicoberry C, García-Peña FJ, Pereira-Bueno J, Costas E, Ortega-Mora LM. Herd-level risk factors associated with Leptospira spp. seroprevalence in dairy and beef cattle in Spain. Prev Vet Med 2001; 52:109-17. [PMID: 11679169 DOI: 10.1016/s0167-5877(01)00249-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Our aim in this cross-sectional study was to investigate the seroprevalence of Leptospira spp. infection in herds and cattle and the relationships between seroprevalence and beef versus dairy, size, replacement policy and grazing management in a representative area of beef- and dairy-cattle production in Spain. Herds were the initial sampling unit. Blood samples were collected from 762 dairy cattle belonging to 81 herds and 1238 beef cattle from 134 herds; sera were tested for antibodies against 11 serovars of Leptospira (autumnalis, ballum, bratislava, canicola, castellonis, copenhagheni, grippotyphosa, hardjo, louisiana, pomona and tarassovi) using the microagglutination test. Forty-three percent (36.2-49.5%) of the herds and 8% (6.4-8.8%) of the individuals were seropositive against one or more of the serovars studied. Bratislava was the most-prevalent serovar (24% of the herds and 4% of the individuals) followed by hardjo (11 and 1%, respectively). Grippotyphosa, copenhagheni and tarassovi were more prevalent in dairy than in beef herds (P<0.001, P<0.05, P<0.05, respectively) -- but no significant association was found between herd-size and Leptospira seroprevalence for any of the serovars considered.
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Affiliation(s)
- C Alonso-Andicoberry
- Facultad de Veterinaria, Departamento de Sanidad Animal, Universidad Complutense de Madrid, 28040-Madrid, Spain
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Guitián FJ, García-Peña FJ, Oliveira J, Sanjuán ML, Yus E. Serological study of the frequency of leptospiral infections among dairy cows in farms with suboptimal reproductive efficiency in Galicia, Spain. Vet Microbiol 2001; 80:275-84. [PMID: 11337143 DOI: 10.1016/s0378-1135(01)00306-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Between March 1996 and September 1997, 15 farms located in Galicia (NW Spain) and experiencing suboptimal reproductive efficiency were visited and blood samples were obtained from all the lactating cows (n=442). Additionally, 1060 samples were obtained monthly from a cohort of 219 lactating cows belonging to nine of the farms between March 1996 and April 1997. All the samples were tested by microscopic agglutination (MAT) using live antigens representing the following Leptospira interrogans serogroups: Australis, Autumnalis, Ballum, Canicola, Grippotyphosa, Icterohaemorrhagiae, Louisiana, Pomona, Sejroe, Shermani and Tarassovi. Eighty-one of the 442 cows were positive against one or more serogroups (P=18.33%). Serologically, L. bratislava and L. grippotyphosa were detected as the most prevalent serovars (P=7.92 and 7.69%, respectively) and as the serovars against which the probability of seroconversion was highest (P=0.27 and 0.25, for a 12-month period, respectively) among those studied. The proportional hazards regression method was used for evaluating the seasonal trend of seroconversions against these two serovars. The risk of seroconversion against L. grippotyphosa was significantly higher during spring. The risk of seroconversion against L. bratislava did not differ significantly among seasons. Our results suggest that infections by L. bratislava did not follow, among the study animals and during the study period, the pattern typically described for non-adapted serovars, pointing out the possibility that some strains of this serovar could behave as adapted serovars.
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Affiliation(s)
- F J Guitián
- Patología Infecciosa y Epidemiología, Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Santiago de Compostela, Campus Universitario s/n. 27002, Lugo, Spain.
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