Soroprevalência e fatores de risco para Babesia bovis em rebanhos leiteiros na região sul de minas gerais

Abstract

RESUMOConduziu-se este trabalho, com o objetivo de determinar a prevalência e os fatores de risco associados à soropositividade para Babesia bovis em 556 bovinos leiteiros procedentes de dez propriedades localizadas no sul de Minas Gerais, as quais foram divididas em dois grupos de acordo com a produção média diária de leite: Alta Produção (AP) >2.000 l de leite/dia, e Baixa Produção (BP) 500 l de leite/dia. Os soros foram submetidos à reação de imunofluorescência indireta (RIFI) para pesquisa de anticorpos anti-B. bovis e considerados positivos na diluição de 1:320. A análise estatística foi realizada no programa SPSS 12.0 for Windows e se buscou determinar a associação entre níveis de positividade para B. bovis nos rebanhos e os fatores de risco por meio do Teste Exato de Fischer. Para testar a diferença das médias de soropositividade, foi utilizado o teste T Student e em todos os cálculos considerou-se o grau de significância de 95%. A prevalência média global de bovinos infectados por B. bovis foi de 94,1% (523/556). Não houve diferença significativa na frequência média de anticorpos anti-B. bovis entre as propriedades leiteiras dos grupos de AP (95,97%) e BP (92,22%); e o mesmo resultado foi observado entre os animais jovens e adultos de ambos os grupos. Não foi observada associação significativa entre os fatores de risco avaliados e a taxa de bovinos positivos para B. bovis. A alta prevalência de rebanhos leiteiros soropositivos permite caracterizar, epidemiologicamente, a microrregião de Lavras, sul de Minas Gerais, como área de elevada estabilidade endêmica para B. bovis. Termos para indexação:Babesiose, bovinos leiteiros, reação de imunofluorescência indireta (RIFI), tristeza parasitária bovina. ABSTRACTThe objective of this study was to determine the prevalence and risk factors associated with Babesia bovis infection in 556 dairy cattle from ten properties located in southern Minas Gerais State, Brazil. The herds were divided into two groups according to average daily milk production (liters): I-High Production (HP), >2,000 L milk/day; and II-Low Production (LP), d"500 L milk/day. The serum samples were submitted to the indirect fluorescent antibody test (IFAT) for antibodies anti-B. bovis and they were considered positive at a dilution of 1:320. The statistical analysis was performed using SPSS 12.0 for Windows. It was stated the association between positivity levels for B. bovis in dairy herds and the risk factors (farm size, production system, breed and feeding system) by Fisher exact test. The average prevalence of cattle with B. bovis infection was 94.06% (523/556). There was no significant difference (p>0.05) in the average frequency of antibodies anti-B. bovis between the groups of HP (95.97%) and LP (92.22%), and similar results were observed between young or adult cattle for both groups. The association between risk factors and seroprevalence of B. bovis has not been previously reported (p>0.05). The high prevalence of seropositive dairy herds allows to characterize epidemiologically the micro...

Detecção de hemoparasitos em bovinos leiteiros do estado do Espírito Santo

“…farms (all categories together) showed that farms D and E presented the biggest difference between the percentage of seropositive for B. bovis and B. bigemina. Despite the study conducted by Guimarães et al (2011) demonstrate that the breeding system did not interfere with the seropositivity of animals, in our research this factor may have interfered, once cows and calves from farm D were housed in the free stall and suspended individual stalls, while in farm E animals were housed on pasture, being more exposed to Rhipicephalus microplus. This is evident once from the 31 animals sampled from farm D only eight presented ticks, while in all 22 animals from farm E ticks were detected (Table 4).…”

Neospora caninum antibodies in dairy cattle of Lages Municipality, Santa Catarina State, Brazil

“…Alternatively, Ogawa et al (2005), Vogel et al (2006), Corbellini et al (2006) and Oshiro et al (2007) reported lower seropositive values of 12%, 11.4%, 17.8% and 14.9%, respectively. In contrast, Boaventura et al (2006), Guimarães et al (2006), Locatelli-Dittrich et al (2008) and Benetti et al (2009), found 40.7%, 90%, 33% and 53.5% of positive animals had antibodies against N. caninum. Ragozo et al (2003) and Guimarães Junior et al (2004) both reported the highest rates of seropositivity were from older cows.…”

Dynamics of natural infection by Babesia bovis and Babesia bigemina in dairy cattle from an enzootic instability area in Northeastern Brazil

“…(B.) microplus, influencing the mortality of larvae in the pastures due to caloric stress (SANTOS-JÚNIOR et al, 2000;GUIMARÃES et al, 2011) and the intensity of infection of these ticks by Babesia spp. (QUINTÃO-SILVA & RIBEIRO, 2003).…”