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Sevá ADP, Chiebao DP, Brandão APD, Godoy SN, Jimenez-Villegas T, Pena HFJ, Ferreira F. Seroprevalence and incidence of Toxoplasma gondii and Neospora caninum infection in naturally exposed domestic dogs from a rural area of São Paulo state, Brazil. ACTA ACUST UNITED AC 2020; 29:e008820. [PMID: 33027425 DOI: 10.1590/s1984-29612020053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 06/02/2020] [Indexed: 11/21/2022]
Abstract
Dogs are hosts of the protozoans Toxoplasma gondii, which causes an important public health disease, and Neospora caninum. Studies that have evaluated toxoplasmosis and neosporosis for prolonged periods in dog populations are rare. We analyzed infection by both parasites in a domestic dog population over three consecutive years in São Paulo state, Brazil. In the 1st, 2nd and 3rd years of collection, 181, 193 and 172 domiciles were visited, and blood samples of 331, 371 and 348 dogs were collected for antibody serology, respectively. The seroprevalence of T. gondii in each year was 27.2%, 22.5% and 43.9%, respectively, and that of N. caninum was 7.8%, 4.8% and 6.8%, respectively. The incidence rates for T. gondii in the 2nd and 3rd collections were 13.2% and 30.0%, and those for N. caninum were 3.3% and 4.4%, respectively. Positive and negative serological conversions for both agents occurred at high frequencies during the study period. This study reveals the canine population's serological profile and demonstrates the constant exposure of dogs to the investigated pathogens, indicating the need for prevention and control measures in the region.
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Affiliation(s)
- Anaiá da Paixão Sevá
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo - USP, São Paulo, SP, Brasil.,Departamento de Ciências Exatas e Tecnológicas, Universidade Estadual de Santa Cruz - UESC, Ilhéus, BA, Brasil
| | - Daniela Pontes Chiebao
- Centro de Pesquisa de Sanidade Animal, Instituto Biológico de São Paulo, São Paulo, SP, Brasil
| | - Ana Perola Drulla Brandão
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Silvia Neri Godoy
- Instituto Chico Mendes de Conservação da Biodiversidade, São Sebastião, SP, Brasil
| | - Tatiana Jimenez-Villegas
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Hilda Fátima Jesus Pena
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Fernando Ferreira
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo - USP, São Paulo, SP, Brasil
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Dwinata IM, Oka IBM, Agustina KK, Damriyasa IM. Seroprevalence of Neospora caninum in local Bali dog. Vet World 2018; 11:926-929. [PMID: 30147261 PMCID: PMC6097554 DOI: 10.14202/vetworld.2018.926-929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 06/01/2018] [Indexed: 01/04/2023] Open
Abstract
Aim: The aim of this research was to identify the seroprevalence of Neospora caninum in local Bali dogs. Materials and Methods: A total of 147 local Bali dog serum samples have been examined for antibodies of N. caninum using enzyme-linked immunosorbent assay test. Results: The results confirmed that 5 (3.4%) local Bali dogs have antibody for N. caninum. There were no significant differences in seroprevalence of Neospora infection in local Bali dogs between different genders, ages, and take care methods (p>0.05). Conclusion: The results provided evidence for the presence of N. caninum infection in local Bali dogs and thus the risk to Bali cattle and dog health.
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Affiliation(s)
- I Made Dwinata
- Department of Parasitology, Faculty of Veterinary Medicine, Udayana University, PB. Sudirman St. Campus, Denpasar, Bali 80223, Indonesia
| | - Ida Bagus Made Oka
- Department of Parasitology, Faculty of Veterinary Medicine, Udayana University, PB. Sudirman St. Campus, Denpasar, Bali 80223, Indonesia
| | - Kadek Karang Agustina
- Department of Public Health, Faculty of Veterinary Medicine, Udayana University, PB. Sudirman St. Campus, Denpasar, Bali 80223, Indonesia
| | - I Made Damriyasa
- Department of Clinical Pathology and Diagnosis, Faculty of Veterinary Medicine, Udayana University, PB. Sudirman St. Campus, Denpasar, Bali 80223, Indonesia
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Cantón GJ, Katzer F, Benavides-Silván J, Maley SW, Palarea-Albaladejo J, Pang Y, Smith S, Bartley PM, Rocchi M, Innes EA, Chianini F. Phenotypic characterisation of the cellular immune infiltrate in placentas of cattle following experimental inoculation with Neospora caninum in late gestation. Vet Res 2013; 44:60. [PMID: 23876124 PMCID: PMC3726360 DOI: 10.1186/1297-9716-44-60] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 07/08/2013] [Indexed: 11/17/2022] Open
Abstract
Despite Neospora caninum being a major cause of bovine abortion worldwide, its pathogenesis is not completely understood. Neospora infection stimulates host cell-mediated immune responses, which may be responsible for the placental damage leading to abortion. The aim of the current study was to characterize the placental immune response following an experimental inoculation of pregnant cattle with N. caninum tachyzoites at day 210 of gestation. Cows were culled at 14, 28, 42 and 56 days post inoculation (dpi). Placentomes were examined by immunohistochemistry using antibodies against macrophages, T-cell subsets (CD4, CD8 and γδ), NK cells and B cells. Macrophages were detected mainly at 14 days post inoculation. Inflammation was generally mild and mainly characterized by CD3+, CD4+ and γδ T-cells; whereas CD8+ and NK cells were less numerous. The immune cell repertoire observed in this study was similar to those seen in pregnant cattle challenged with N. caninum at early gestation. However, cellular infiltrates were less severe than those seen during first trimester Neospora infections. This may explain the milder clinical outcome observed when animals are infected late in gestation.
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Ghalmi F, China B, Kaidi R, Losson B. Neospora caninum Is Associated With Abortion In Algerian Cattle. J Parasitol 2011; 97:1121-4. [DOI: 10.1645/ge-2861.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Uzeda RS, Costa KDS, Santos SL, Pinheiro AM, De Almeida MAO, McAllister MM, Gondim LFP. Loss of infectivity of Neospora caninum oocysts maintained for a prolonged time. THE KOREAN JOURNAL OF PARASITOLOGY 2008; 45:295-9. [PMID: 18165712 DOI: 10.3347/kjp.2007.45.4.295] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The purpose of this study was to investigate whether sporulated Neospora caninum oocysts, which had been stored for 46 mo in a 2% sulfuric acid solution at 4 degrees C, remain morphologically viable and infective to gerbils (Meriones unguiculatus). Six gerbils were orally inoculated with doses of 400 or 1,200 oocysts. Two mo after inoculation, the animals did not show any clinical signs, had no histological lesions, and were seronegative for N. caninum at 1: 50 in an immunofluorescent antibody test. PCR using the brain from each gerbil did not reveal N. caninum specific DNA. We conclude that oocysts preserved for 46 mo are not infective, despite being morphologically intact.
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Affiliation(s)
- Rosangela Soares Uzeda
- Universidade Federal da Bahia, Escola de Medicina Veterinaria, Departamento de Patologia e Clinicas, Avenida Ademar de Barros, 500, Ondina, Salvador, Bahia, 40170-110, Brazil
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Ferroglio E, Pasino M, Romano A, Grande D, Pregel P, Trisciuoglio A. Evidence of Neospora caninum DNA in wild rodents. Vet Parasitol 2007; 148:346-9. [PMID: 17651897 DOI: 10.1016/j.vetpar.2007.06.031] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Revised: 06/20/2007] [Accepted: 06/21/2007] [Indexed: 11/22/2022]
Abstract
Seventy-five house mice (Mus musculus), 103 rats (Rattus norvegicus) and 55 field mice (Apodemus sylvaticus) from North-West Italy were PCR analysed for Neospora caninum infection. Brain, kidney and muscle tissues collected from the above mentioned animals were tested by PCR using Np6 and Np21 primers. The brain tissue from 2 house mice and 2 rats, the kidney from 4 rats, 1 house mouse and 1 field mouse and muscle from 10 rats, 8 house mice and 1 field mouse were tested positive for N. caninum. Sequencing showed a 96-97% identity of PCR products with N. caninum NC1 sequence. Our findings support previous report on house mouse and rat, and for the first time, provides the evidence of the infection also in field mice. Based on our data, it could be hypothesized that mice can act as a reservoir of N. caninum, and they can play a role in maintaining/spreading N. caninum infection also in the sylvatic cycle. The possibility that dogs could be infected by eating infected house mice suggests new opportunities for N. caninum prophylaxis and control.
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Affiliation(s)
- E Ferroglio
- Dipartimento di Produzioni Animali, Epidemiologia ed Ecologia, Università di Torino, Via L. Da Vinci 44, 10095 Grugliasco (TO), Italy.
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Corbellini LG, Smith DR, Pescador CA, Schmitz M, Correa A, Steffen DJ, Driemeier D. Herd-level risk factors for Neospora caninum seroprevalence in dairy farms in southern Brazil. Prev Vet Med 2006; 74:130-41. [PMID: 16343669 DOI: 10.1016/j.prevetmed.2005.11.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Revised: 10/28/2005] [Accepted: 11/04/2005] [Indexed: 10/25/2022]
Abstract
A cross-sectional study was used to test the relationship between herd seroprevalence to Neospora caninum and various potential herd-level risk factors in 60 dairy farms located in two distinct regions in southern Brazil. Thirty farms were randomly selected from within each region. A questionnaire was designed to summarize each farm's production system as it might relate to N. caninum transmission. The questionnaire contained 105 closed questions relating to general characteristics of the farms, farm facilities, management, source of food and water, herd health, environment and biosecurity, which included questions relevant to N. caninum transmission, including presence and number of dogs and other animals, purchase of animals and contact with man. Serum samples were collected from 40% of animals in each farm and N. caninum antibodies were detected by immunofluorescent antibody test (IFAT). The association between potential risk factors and the probability of an animal being seropositive was modeled using a generalized estimation equations (GEE) logistic regression model. The model accounted for multilevel correlation of data from multiple animals within herds. The mean (+/-S.D.) number of animals in the 60 herds was 64.5 (+/-45.6), ranging from 20 to 280 females. Blood samples were collected from 1549 animals. The size of the farms varied from 4 to 100 ha (mean 30.1+/-25.9 ha). At least one dog was found in 57 of the 60 dairy farms (95%). The mean number of dogs was 3.1 (+/-1.9), ranging from 0 to 10. All females were raised on pasture. For all cattle sampled, N. caninum seroprevalence was 17.8%. Overall, 93.3% of herds (56/60) had at least one seropositive animal identified. Four variables were significantly associated with N. caninum sero-response in the 57 dairy farms, which were included in the final multivariable model: the number of dogs on the farm, farm area (hectares), feeding pooled sources of colostrum and region. The odds of a cow being seropositive increased 1.13 times for each additional dog present on the farm (P=0.021). Cattle from farms that fed calves colostrum pooled from multiple cows had 1.79 times greater odds for being seropositive for N. caninum (P<0.003). The probability of being seropositive was inverse to the area of the farms, such that cattle had 0.92 times the odds to be seropositive (P=0.014) for each additional 10 ha of farmland. Finally, cattle from farms in region one had 0.71 times the odds to be seropositive than cattle from region two (P=0.035). Results of this study suggest that several risk factors may explain why dairy cattle in Brazil may become exposed to N. caninum. However, further investigation of these factors is necessary because the purpose of this study was to refine and generate hypotheses on N. caninum transmission.
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Affiliation(s)
- Luis G Corbellini
- Laboratory of Veterinary Pathology, Faculty of Veterinary, Federal University of Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9090, CEP 91540-000, Porto Alegre, RS, Brazil.
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8
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Cabaj W, Moskwa B, Pastusiak K, Gill J. Antibodies to Neospora caninum in the blood of European bison (Bison bonasus bonasus L.) living in Poland. Vet Parasitol 2004; 128:163-8. [PMID: 15725547 DOI: 10.1016/j.vetpar.2004.09.033] [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] [Received: 05/07/2004] [Revised: 09/27/2004] [Accepted: 09/27/2004] [Indexed: 10/26/2022]
Abstract
The prevalence of antibodies to Neospora caninum was examined in European bison (Bison bonasus bonasus L.) living in free and fenced areas in Poland. Sera of 320 European bison, different ages and sexes, from breeding areas in Poland were tested for N. caninum antibodies using ELISA test. Positive antibody responses were found in 23 bison (prevalence 7.3%). Additionally, all positive sera were tested by Western blot to verify the ELISA results. The Western blot results confirmed the presence of antibodies to Neospora tachyzoites antigens in all 23 sera tested. The antibodies were detected against a wide range of NC-1 tachyzoite antigens. The antibody responses were directed against proteins at: 9.5, 17, 21, 27, 31, 36.5, 38, 40, 43, 47, 48.5, 53.5 and 58 kDa. The most heavily stained bands had molecular weights of 9.5, 17, 27 and 58 kDa. The most important is that antibody to N. caninum was detected for the first time in sera from bison cow shot in 1988. It is the year of recognition of this protozoan parasite. Our results indicate strongly the presence of N. caninum in European bison in Poland and suggest that a sylvatic cycle of N. caninum can exist. However, further studies are needed to evaluate the existence of a sylvatic cycle of N. caninum. The study on the effect of the infection on the health status and conservation of European bison should be taken under consideration too.
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Affiliation(s)
- W Cabaj
- Witold Stefanski Institute of Parasitology of the Polish Academy of Sciences, 00-818 Warszawa, ul. Twarda 51/55, Poland.
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9
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Gondim LFP, McAllister MM, Pitt WC, Zemlicka DE. Coyotes (Canis latrans) are definitive hosts of Neospora caninum. Int J Parasitol 2004; 34:159-61. [PMID: 15037103 DOI: 10.1016/j.ijpara.2004.01.001] [Citation(s) in RCA: 341] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Four captive-raised coyote pups consumed tissues from Neospora caninum-infected calves. Faeces were examined from 4 days before to 28 days after infection. One pup shed N. caninum-like oocysts, which tested positive for N. caninum and negative for Hammondia heydorni using PCR tests. Coyotes are the second discovered definitive host of N. caninum, after dogs. In North America, the expanding coyote ranges and population increase the probability of contact with domestic livestock. To reduce the risk of transmission of N. caninum to intensively farmed cattle, we recommend protection of feedstuffs using canid-proof fences, and careful disposal of dead stock.
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Affiliation(s)
- Luis F P Gondim
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, 2001 South Lincoln Avenue, Urbana, IL 61802, USA
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Locatelli-Dittrich R, Richartz RRTB, Joineau MEG, Pinckney RD, de Sousa RS, Leite LC, Thomaz-Soccol V. Isolation of Neospora caninum from a blind calf in Paraná, southern Brazil. Vet Rec 2003; 153:366-7. [PMID: 14533770 DOI: 10.1136/vr.153.12.366] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- R Locatelli-Dittrich
- Departamento de Medicina Veterinária, Universidade Federal do Parana, Rua dos Funcionários, 1540, CEP 80035 - 050, Curitiba, Paraná, Brazil
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Gondim LFP, Gao L, McAllister MM. Improved production of Neospora caninum oocysts, cyclical oral transmission between dogs and cattle, and in vitro isolation from oocysts. J Parasitol 2002; 88:1159-63. [PMID: 12537111 DOI: 10.1645/0022-3395(2002)088[1159:iponco]2.0.co;2] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Scarce information is available about Neospora caninum oocysts and sporozoites, in part because only small numbers of oocysts have typically been produced by experimentally infected dogs. We hypothesized that I reason for low experimental production of oocysts is that dogs have been fed tissues from experimentally infected mice instead of tissues from cattle (which are natural intermediate hosts of N. caninum). In this study, 9 dogs were fed tissues from N. caninum-infected calves, and oocyst production was compared with 6 dogs that were fed infected mouse carcasses. The number of oocysts produced by dogs that ingested infected calf tissues (mean = 160,700) was significantly greater (P = 0.03) than the number of oocysts shed by dogs that ingested infected mice (mean = 5,400). The second goal of our experiment was to demonstrate cyclical oral transmission of N. caninum between dogs and cattle. As few as 300 oocysts were used to successfully infect calves, and tissues from these calves induced patent infections in 2 of 3 dogs; oocysts from I of these dogs were administered to another calf, and tissues from this calf subsequently induced a third dog to shed oocysts. Oocysts were confirmed to be N. caninum using a species-specific polymerase chain reaction technique. In addition, sporulated oocysts were used to recover N. caninum in vitro after digestion in an acid-pepsin solution and inoculation of cell monolayers.
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Affiliation(s)
- L F P Gondim
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, 2001 South Lincoln Avenue, Urbana, Illinois 61802, USA
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Slapeta JR, Koudela B, Votýpka J, Modrý D, Horejs R, Lukes J. Coprodiagnosis of Hammondia heydorni in dogs by PCR based amplification of ITS 1 rRNA: differentiation from morphologically indistinguishable oocysts of Neospora caninum. Vet J 2002; 163:147-54. [PMID: 12093189 DOI: 10.1053/tvjl.2001.0599] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Hammondia heydorni is thought to be a non-pathogenic coccidian parasite of dogs that is closely related to Neospora caninum, an important parasite of cattle and dogs. Oocysts of these two species are morphologically indistinguishable from each other. A population of 2240 dogs in the Czech Republic was screened for the presence of H. heydorni/N. caninum oocysts and five (0.22%), represented by five of 3135 faecal samples (0.16%), were positive. The internal transcribed spacer 1 region of the rRNA gene (ITS1) from two isolates were cloned and the DNA sequences were identical with those of the ITS1 of H. heydorni. Based on the rRNA sequences available for H. heydorni and related coccidia, the primer pair JS4-JS5 was designed to amplify the 3' end of the small subunit (SSU) rRNA gene and ITS1 of H. heydorni. When tested on DNA extracted from a variety of parasites, the primers amplified a specific 267 bp fragment in our isolates only. The presence of DNA equivalent to 10 oocysts was sufficient for the amplification of the ITS1. We present a PCR-based diagnostic method as the only fast and reliable method for the diagnosis of H. heydorni in dogs.
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Affiliation(s)
- J R Slapeta
- Department of Parasitology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic.
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Modrý D, Václavek P, Koudela B, Slapeta JR. Placentophagia--an alternative way for horizontal transmission of Neospora caninum in cattle? Trends Parasitol 2001; 17:573-5. [PMID: 11756037 DOI: 10.1016/s1471-4922(01)02144-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Bergeron N, Fecteau G, Villeneuve A, Girard C, Paré J. Failure of dogs to shed oocysts after being fed bovine fetuses naturally infected by Neospora caninum. Vet Parasitol 2001; 97:145-52. [PMID: 11358630 DOI: 10.1016/s0304-4017(01)00396-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Neospora caninum is a protozoan that causes abortion in cattle. The dog has recently been identified as a definitive host for N. caninum. To verify if bovine fetuses can infect dogs, nine 2-4-month-old dogs were fed bovine fetuses naturally infected by N. caninum. None of the dogs excreted oocysts, seroconverted, had clinical signs or lesions compatible with N. caninum infection. Additional studies will be necessary to determine the natural mode of infection of dogs by N. caninum.
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Affiliation(s)
- N Bergeron
- Faculté de Médecine Vétérinaire, Département de Sciences Cliniques, Université de Montréal, C.P. 5000, St-Hyacinthe, Qué., Canada J2S 7C6
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Dijkstra T, Barkema HW, Eysker M, Wouda W. Evidence of post-natal transmission of Neospora caninum in Dutch dairy herds. Int J Parasitol 2001; 31:209-15. [PMID: 11239942 DOI: 10.1016/s0020-7519(00)00160-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Eighteen dairy herds with neosporosis-associated abortions were analysed for antibodies against Neospora caninum. Blood samples of all cows, heifers and calves were collected on the same day for each farm. A total of 2430 heads of cattle were examined. For each herd, the seropositive and seronegative animals were plotted against month of birth. Analysis of seroprevalence in relation to age showed an equal distribution of seropositives in all age-groups in 10 herds. In contrast, in eight herds an age-group could be identified which had a significantly higher seroprevalence than the other animals in the herd. Most seropositive animals in the high seroprevalence age-groups had either seronegative dams or seronegative offspring, whereas there was a strong relationship between the serostatus of dams and offspring in the other animals in the herd. Aborting animals were mainly part of the high seroprevalence age-group. These findings strongly indicate a post-natal infection of the animals in the high seroprevalence age-groups, probably due to a point source exposure to N. caninum.
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Affiliation(s)
- T Dijkstra
- Animal Health Service, P.O. Box 361, 9200 AJ, The, Drachten, Netherlands.
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Abstract
Since the identification of Neospora caninum in 1984 as a parasite separate from Toxoplasma gondii by Bjerkas et al., and its subsequent characterization and classification in 1988 by Dubey and co-workers, this parasite has attracted increasing attention, primarily as an important causative agent of abortion in cattle and neuromuscular disease in dogs, but also as a complementary model system to T. gondii for investigating the basic biology of intracellular parasitism. During November 11-14, 1999, the COST 820 Annual meeting (Vaccines against coccidioses) took place in Interlaken, Switzerland. Almost half of the papers presented at that meeting were on N. caninum and neosporosis, reflecting the increasing awareness of the importance of this parasite on part of the scientific community in Europe. On the occasion of the meeting, participants in this COST Action involved in Neospora research in Europe were asked to participate in this invited review in order to document the growing interest in N. caninum and the disease it causes. Thus, this paper is a unique collection of contributions provided by several European experts in the field. It is comprised of 10 reviews or original papers on different aspects of Neospora research including epidemiology, immunology, application and development of serological tools, and molecular characterisation of the parasite currently carried out throughout Europe. In addition, two distinguished invited speakers from overseas (Milton McAllister and John Ellis) provided valuable contributions. This invited review demonstrates that the COST 820 Action has brought together scientists from all over Europe and other parts of the world, and has laid the basis for many fruitful collaborations. The studies described here will contribute in assessing the relevance of neosporosis as a potential risk factor not only for animals, but also for human health.
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Affiliation(s)
- A Hemphill
- Institute of Parasitology, University of Berne, Länggass-Strasse 122, CH-3012, Bern, Switzerland.
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Atkinson R, Harper PA, Reichel MP, Ellis JT. Progress in the serodiagnosis of Neospora caninum infections of cattle. PARASITOLOGY TODAY (PERSONAL ED.) 2000; 16:110-4. [PMID: 10689330 DOI: 10.1016/s0169-4758(99)01604-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Neospora caninum is an apicomplexan protozoan that has become the focus of significant research attention worldwide. This organism infects a range of host species, including dogs, from which it was originally reported in 1984, but it is most important as a major cause of bovine abortion. As a result of the global importance of N. caninum, researchers have developed a number of serological tests to investigate the epidemiology of infection and disease. In this article, Robert Atkinson, Peter Harper, Michael Reichel and John Ellis consider progress made in the serodiagnosis of N. caninum.
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Affiliation(s)
- R Atkinson
- Molecular Parasitology Unit, Department of Cell and Molecular Biology, University of Technology, Sydney, Westbourne Street, Gore Hill, NSW 2065, Australia
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Morgan UM, Xiao L, Fayer R, Lal AA, Thompson RC. Variation in Cryptosporidium: towards a taxonomic revision of the genus. Int J Parasitol 1999; 29:1733-51. [PMID: 10616920 DOI: 10.1016/s0020-7519(99)00109-5] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Cryptosporidium is an important cause of enteric disease in humans and other animals. Limitations associated with conventional diagnostic methods for cryptosporidiosis based on morphological features, coupled with the difficulty of characterising parasites isolated in the laboratory, have restricted our ability to clearly identify species. The application of sensitive molecular approaches has obviated the necessity for laboratory amplification. Such studies have found considerable evidence of genetic heterogeneity among isolates of Cryptosporidium from different species of vertebrate, and there is now mounting evidence suggesting that a series of host-adapted genotypes/strains/species of the parasite exist. In this article, studies on the molecular characterisation of Cryptosporidium during the last 5 years are reviewed and put into perspective with the past and present taxonomy of the genus. The predictive value of achieving a sound taxonomy for the genus Cryptosporidium with respect to understanding its epidemiology and transmission and controlling outbreaks of the disease is also discussed.
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Affiliation(s)
- U M Morgan
- World Health Organisation Collaborating Centre for the Molecular Epidemiology of Parasitic Infections, and State Agricultural Biotechnology Centre, Murdoch University, Australia.
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