Prevalência de brucelose bovina entre rebanhos fornecedores de leite de um laticínio em Itirapuã, estado de São Paulo

The aim of this study was to verify the prevalence of bovine brucellosis among milk suppliers of a dairy industry located in Itirapua, Sao Paulo, Brazil, and to analyze the risk factors eventually associated with the occurrence of brucellosis among the herds involved in the study A voluntary sample of 813 animals from 37 herds whose owners agreed to participate in the study was obtained among a population of 942 adult cattle from 55 herds located in the municipalities of Itirapua and Patrocinio Paulista. A questionnaire about risk factors that could be associated with the prevalence rates was applied. Serum samples from all 813 animals were collected and tested by the rose Bengal plate test (RBPT); positive samples were then tested by the complement fixation test (CFT). Of the 813 serum samples, 26 (3.2%) tested positive in the serial application of RBPT and CFT, and of the 37 herds, 12 (32.4%) had at least one positive animal. Factors that showed association with the prevalence rate were number of animals in the herd, lack of vaccination with strain B19 and frequent introduction of animals.