Frequência de anticorpos contra o vírus da Diarreia Viral Bovina (BVDV) em bovinos leiteiros não vacinados no estado do Maranhão

Abstract

The Bovine Viral Diarrhea Virus (BVDV) has a wide world distribution and it is considered one of main bovine pathogens. It is responsible for economic losses in the productive and reproductive sphere. In this way, the research was realized, with the objective to establish the frequency of antibodies against the bovine viral diarrhea virus in the state of Maranhão dairy basin. Serum sanguine samples of 920 bovine females not vaccined against the diarrhea viral bovine (BVD) were analysed through the indirect ELISA technique. The study was realized in 92 dairy properties, belonging to 23 districts located in the regions of Açailândia, Bacabal, São Luiz island, Imperatriz and Pedreiras. The serum samples were collected from females with or without BVDV infection clinical signals and stratified according to aged band (> 3 years, between 3 and 7 years and > 7 years). It was applied an epidemiological questionnaire during the sample collect to research the factors that could be associated to infection. From the 920 serum analysed samples, 65.66% (n=604) were reagents, 3.80% (n=35) suspected and 30.54% (n=281) not reagents. In the regional samples, they obtained frequency of 67.5% (n=108), 53.57% (n=150), 80% (n=96), 63.75% (n=102) and 74% (n=148), for São Luiz island, Imperatriz, Açailândia, Pedreiras and Bacabal, respectively. In the 23 studied districts reagents animals were found, with detection of serological positives bovines in 94.57% properties. It was not observed significative difference (P=0.21) in the aged band of stratified population. From the considered variables as risk factors for the BVDV infection, the presence of porcine, lack of veterinary assistance, use of natural breeding or natural breeding associated to artificial insemination and diarrhea, presented statistic significance (P<0.05) associated to BVDV seropositivity. The obtained results had demonstrated high levels of frequency and prevalence of BVDV in the state of Maranhão’s dairy aptitude bovine flock. These findings indicate the need of systematic diagnose accomplishment and the flock monitoring, beyond the implementation of control and prophylaxis measures, as a gradual removal of infected animals, accomplishment of quarantine of new animals added in the proprieties, accomplishment of serological exams and vaccination.