Seroprevalence, spatial analysis and risk factors of infection with Neospora caninum in cattle in Brazil’s northern Pantanal wetland

Abstract

Neosporosis is caused by an obligate intracellular protozoan, Neospora caninum . It is considered one of the most widespread and frequent causes of abortion in cattle worldwide. To evaluate the prevalence of anti-N. caninum antibodies and associated risk factors, serum samples were collected from 2,452 bovines at 262 farms in the northern Pantanal, state of Mato Grosso, Brazil. Each farmer was asked to fill out a questionnaire for subsequent epidemiological data analysis. Anti-N. caninum antibodies were detected by means of the indirect immunofluorescent assay (IFA), using a cut-off dilution of 1:100. The overall anti-N. caninum antibodies prevalence was 25.44% (Confidence Interval - CI 95%; 20.10%; 30.78%), and the anti-N. caninum antibodies prevalence per herd was 76.72% (CI 95%; 71.60%; 81.84%). The presence of dogs, occurrence of abortion in cows, and sale of cattle for breeding were statistically associated with seropositivity in herds, while the risk of females being seropositive for N. caninum was higher in animals ≤ 6-years-old and in the presence of dogs. A spatial analysis indicated that the relative risk of the disease is spatially constant and that the farms with the highest prevalence of anti-N. caninum antibodies are located south of the region under study.

Situação da neosporose na bovinocultura brasileira

“…Chiebao (2010) relatou que os fatores de risco em rebanhos bovinos associadas a N. caninum são a presença de cães, a criação de aves domésticas, o fornecimento de silagem e o tamanho da propriedade. Schmidt et al (2018) em estudo conduzido no Pantanal, norte do Brasil, identificaram também a presença de cães e abortamento das vacas, assim como Nicolino et al (2017) e Vilas Boas ( 2014), e associaram a soropositividade do rebanho avaliado também a idade ≤ 6 anos e venda de bovinos para reprodução. Já Snak et al (2018), além do histórico de aborto, apontaram em sua pesquisa outros fatores de risco, com raça e produção leiteira, apontaram que vacas da raça Jersey e baixa produção de leite como fatores significativos na ocorrência de animais sororeagentes.…”