Soroprevalência e fatores de risco para Brucella spp. em equídeos do estado de Mato Grosso, Brasil

Abstract

The present study investigated the prevalence of brucellosis in equids in the State of Mato Grosso, testing 3,858 samples, including 3,230 horses, 602 mules and 26 donkeys, belonging to a 2014 serum bank, collected in 141 municipalities and covering the three biomes: amazon, cerrado and the pantanal. Samples were initially analyzed by screening using the Acidic Buffered Antigen (AAT) technique, and those that were reactive were later confirmed by the Complement Fixation (CF) technique. The procedures are in accordance with Normative Instruction No. 34, of September 8, 2017 (IN 34 MAPA (Ministry of Agriculture, Livestock and Supply) which deals with the diagnosis of brucellosis. According to the AAT, 173 samples were reactive, 70 samples from the Amazon biome, 56 from the Cerrado and 47 from the Pantanal. Of this total, 30 samples were confirmed in the CF, 14 samples from the amazon biome, 14 from cerrado and 2 from the pantanal biomes. The estimated prevalence for the State of Mato Grosso was 0.82%, while the values in the amazon, cerrado and pantanal biomes were estimated at 0.90%, 0.88% and 0.12%, respectively. Considering by species, 456 (0.65% ) horses, 987 (1.25%) mules and 67 (2.95%) donkeys positive. Regarding the prevalence between sexes, it was observed that females presented 0.86% and males 0.78%. According the age, 0.10% positives are in the age range 6 months to 3 years, 0.92% in the range 3 years to 10 years and 0.92% in the range of animals older than 10 years. Of the properties tested, 27 had positive animals and of these, only 9 had bovines positive for brucellosis, not finding an association with the properties tested for cattle and horses (p>0.05). Based on the results obtained, the prevalence of antiBrucella spp. in horses in the State of Mato Grosso was estimated at 0.82%, and this value is close to those detected in other studies in Brazil. The frequency of antibodies in horses was higher in the Amazon and Cerrado biomes, however the relative risk of foci of equine brucellosis is constant for the entire state. No association was observed between an outbreak of equine brucellosis with cattle or an outbreak of bovine brucellosis.