Sheep abortion associated with Neospora caninum in Mato Grosso do Sul, Brazil

Pinto, Ana Paula; Bacha, Flávia Barbieri; Santos, Bethania Silva; Driemeier, David; Antoniassi, Nadia Aline Bobbi; Ribas, Nickolly Lilge Kawski de Sá; Lemos, Ricardo A.A.

doi:10.1590/s0100-736x2012000800010

Cited by 15 publications

(12 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A transmissão também pode ser vertical via transplacentária, que possui grande importância pois o animal clinicamente sadio se torna cronicamente infectado (Dubey & Acland 1992). A infecção possui grande importância econômica, principalmente devido às perdas reprodutivas, incluindo retornos ao cio, com intervalos regulares ou irregulares, abortos, nascimento de animais fracos e inviáveis, com sinais neurológicos, ou persistentemente infectados (Dubey & Lindsay 1996, Pinto et al 2012.…”

Section: Introductionunclassified

Pesquisa de anticorpos IgG para Neospora caninum e avaliação dos fatores de risco em ovinos do Estado de Sergipe

et al. 2017

View full text Add to dashboard Cite

The aim of this study was to determine the occurrence of antibodies IgG against Neospora caninum and evaluate the risk factors associated with the infection in ovine herds, State of Sergipe, Brazil. Blood samples (n=1200) were collected from sheep raised in 60 sheep run located in the three mesoregions of the State of Sergipe, between 2011 e 2012. Antibodies were investigated by Indirect Immunofluorescence Antibody Test of which cutoff point was 50 and positive samples were diluted in base 2 until the last positive titer. Data from 15 variables was obtained from questionnaires given to farmers. Absolute and relative frequencies were determined and the risk factors were analyzed by Pearson's Qui-Square test (p≤0,05). The occurrences of serum reactive sheep were 39.83% (478/1200). The occurrences of positive sheep and sheep run were 55.88% (380/680) and 88.24% (30/34) in the Eastern region; 21.42% (60/280) e 42.85% (6/14) in dry region and 15.83% (38/240) e 41.67% (5/12) in the backwoods respectively. Antibody titers ranged from 50 (n=459), represented 96.02% (459/478) of seropositive samples to 6400 (1/478). Among the significant variables in the multivariate analysis were considered risk factors for infection with N. caninum were, sheep run located in Eastern region (p=0.000, OR=4.64, CI95%=3.36-6.41); standing and running water sources (p=0.000 OR=2.03, CI95%=1.41-2.92), absence of quarantine (p=0.000, OR=2.71, CI95%=2.08-3.53), absence of dunghill (p=0.000, OR=3.14, CI95%=2.45-4.02), presence of dogs (p=0.000, OR=2.74, CI95%=1.73-433), presence of wild animals (p=0.000, OR=3.45, CI95%=2.44-4.87) and subsistence (p=0.000, OR=4.99, CI95%=3.15-7.92) or reproduction (p=0.002, OR=1.74, CI95%=1.22-2.49) livestock were important risk factors. Our results highlight the occurrence of N. caninum in the ovine herds from State of Sergipe. Management and location of sheep runs were important risk factors associated to the infection.INDEX TERMS: Neospora caninum, infection, parasite, sheep, risk factors, indirect fluorescent antibody test.

show abstract

Section: Introductionunclassified

Pesquisa de anticorpos IgG para Neospora caninum e avaliação dos fatores de risco em ovinos do Estado de Sergipe

et al. 2017

View full text Add to dashboard Cite

show abstract

“…In the state of Mato Grosso do Sul, Pinto et al (2012) confirmed vertical transmission of N. caninum in sheep fetuses and observed mild to moderate perivascular mononuclear infiltrate in heart and diffuse gliosis associated with non--suppurative mononuclear cells in brain. One of the brain samples evaluated by Pinto et al (2012) had cysts, which were confirmed as N. caninum cysts by IHC.…”

Section: Discussionmentioning

confidence: 66%

“…There are also reports of abortion in goats naturally infected by N. caninum in the United States (Barr et al 1992, Costa Rica (Dubey et al 1996), Italy (Eleni et al 2004), Spain (Moreno et al 2012) and Argentina (Unzaga et al 2014). In Brazil, N. caninum congenital infection in goats and sheep has been described in the South, Southeast and Midwest regions, with no descriptions in the other regions of the country (Corbellini et al 2001, Pinto et al 2012, Varaschin et al 2012, Mesquita et al 2013). …”

Section: Introductionmentioning

confidence: 99%

Transplacental transmission of Neospora caninum in naturally infected small ruminants from northeastern Brazil

et al. 2017

View full text Add to dashboard Cite

RESUMO.-[Transmissão transplacentária de Neospora caninum em pequenos ruminantes infectados naturalmente do Nordeste do Brasil.] Toxoplasma gondii e Neospora caninum são reconhecidos como protozoário causadores de aborto em ovinos e caprinos. Desta forma, objetivou-se descrever a transmissão transplacentária desses agentes em pequenos ruminantes na região Nordeste do Brasil. Foram examinados seis fetos caprinos e onze fetos ovinos, totalizando 78 amostras de diferentes tecidos (cé-rebro, fígado, pulmão, rim e coração) provenientes de propriedades rurais com histórico de aborto. As amostras foram analisadas por Reação em Cadeia da Polimerase (PCR), Histopatologia (HP) e Imunohistoquímica (IHQ), com a finalidade de associar o abortamento a T. gondii e/ou N. caninum. Nenhuma amostra foi positiva na PCR e IHQ para T. gondii. Algumas amostras de cérebro, fígado, pulmão, rim e coração de fetos de caprinos e ovinos foram positivas na PCR para N. caninum. Na histopatologia foi observado leve infiltrado mononuclear no fígado e necrose com calcificação no SNC de um caprino, associada à imunomarcação positiva para N. caninum na IHQ e PCR positiva. Os resultados confirmam a transmissão vertical de N. caninum em caprinos naturalmente infectados na região nordeste do Brasil. Toxoplasma gondii and Neospora caninum are causative agents of abortion in sheep and goats. Thus, the present study aimed to describe the transplacental transmission of these protozoans in small ruminants of northeastern Brazil. Seventeen fetuses (6 goats and 11 sheep) from farms with history of abortion were necropsied and samples were collected from different tissues (brain, liver, lung, kidney and heart). The samples were analyzed by PCR, histopathology (HP) and immunohistochemistry (IHC) to evaluate whether T. gondii and/ or N. caninum infection were the cause of abortion. None of the samples was positive for T. gondii according to PCR and IHC results. Some brain, liver, lung, kidney and heart samples of goat fetuses were positive for N. caninum by PCR. In the histopathology, mild mononuclear infiltration and necrosis with calcification were observed in the liver and brain of one goat fetus, respectively, that also was positive for N. caninum by PCR and IHC. The results confirmed vertical transmission of N. caninum in naturally infected goats of northeastern, Brazil.

show abstract

“…Neospora caninum and Toxoplasma gondii are closely related cyst-forming apicomplexan parasites identified as important causes of reproductive failure in cattle [13,14]. Abortion cases attributed to N. caninum [12,21,35] and T. gondii [10,20,28,44] infection have been occasionally reported in sheep. These parasites have already been identified in 77% of 74 brain samples from aborted sheep fetuses [23].…”

Section: Introductionmentioning

confidence: 99%

Detection of Neospora caninum and Toxoplasma gondii in Semen of Naturally Infected Rams

Koch

Dittrich

Weiss

et al. 2019

Acta Scientiae. Vet.

View full text Add to dashboard Cite

Background: Neospora caninum and Toxoplasma gondii are closely related cyst-forming apicomplexan parasites identified as important causes of reproductive failure in cattle. Moreover, abortion cases attributed to N. caninum and T. gondii infection have been occasionally reported in sheep. Due to the relatively scarce information on the molecular detection of N. caninum in the semen of naturally infected rams, this study aimed to detect parasitic DNA in fresh semen samples and in frozen extended semen straws from male sheep from artificial inseminations centers in Southern Brazil.Materials, Methods & Results: Semen samples of 38 rams from artificial insemination centers were evaluated. Eleven rams were naturally infected (seropositive for anti-N. caninum and/or anti-T. gondii IgG) and were selected for fresh semen collection. We tested all the samples for the closely related protozoan T. gondii to detect a possible cross-reaction and co-infection, due to the close similarity with N. caninum. The indirect fluorescent antibody test was used to detect IgG antibodies in the 11 serum samples from rams. Fresh semen samples were collected from 11 rams on days 1, 50, 55, and 58 using an artificial vagina and ewe in estrus. Other 27 rams had their frozen extended semen straws analyzed. A total of 20 fresh semen samples and 27 frozen extended semen straws samples were used to detect the presence of N. caninum and T. gondii DNA by polymerase chain reaction (PCR). Nc-5 and B1 genes were used as target regions to detect N. caninum and T. gondii DNA, respectively. The presence of N. caninum DNA was confirmed in the third collection of a fresh semen sample of one seropositive ram. T. gondii DNA was detected in a fresh semen sample of one seropositive ram. The DNA sequences of 186 bp from N. caninum (GenBank accession: MH806393) and 492 bp from T. gondii (GenBank accession: MH793503) were obtained by sequencing, and analysis revealed 99% and 100% identity, respectively, compared with other sequences deposited at GenBank. N. caninum and T. gondii DNAs were not detected in any of the 27 frozen extended semen straws used for artificial insemination.Discussion: This study demonstrated the presence of N. caninum and T. gondii DNA in fresh semen samples of naturally infected rams. The non-detection of N. caninum and T. gondii DNA in frozen semen samples of rams could be due to the dilution that was used to prepare the semen straws (GGL diluent and 5% glycerol), since fresh semen samples were not diluted prior to the test. Moreover, in our study, the volume of frozen semen samples (0.25 mL) used for PCR was lower than the volume of sediment obtained from fresh semen (0.5 mL), and the fresh semen centrifugation to obtain the sediment may have grouped the tachyzoites, increasing the sensitivity of the technique employed. No high IgG serological titers were detected in the rams at the time they were eliminating the parasite through fresh semen. The final titer of anti-N. caninum and anti-T. gondii IgGs in serum was 1:100, suggesting chronic infection. It is suggested that a new parasite elimination pathway is occurring among rams used for reproduction, due to the presence of N. caninum and T. gondii DNA in fresh semen samples from seropositive animals. Although the detection of genomic DNA of N. caninum and T. gondii in semen does not necessarily imply the presence of infectious stages of the parasites and does not determine their viability, these results demonstrate the need for further studies. Our study also indicates the need to reinforce preventive measures for sheep in artificial insemination centers until the risks are evaluated, by performing serological examinations with anti-N. caninum and anti-T. gondii antibodies, for instance, to select the rams that will be used for breeding.

show abstract

Sheep abortion associated with Neospora caninum in Mato Grosso do Sul, Brazil

Cited by 15 publications

References 35 publications

Pesquisa de anticorpos IgG para Neospora caninum e avaliação dos fatores de risco em ovinos do Estado de Sergipe

Pesquisa de anticorpos IgG para Neospora caninum e avaliação dos fatores de risco em ovinos do Estado de Sergipe

Transplacental transmission of Neospora caninum in naturally infected small ruminants from northeastern Brazil

Detection of Neospora caninum and Toxoplasma gondii in Semen of Naturally Infected Rams

Contact Info

Product

Resources

About