Frequency of antibodies Anti-Leptospira Spp. and Anti-Brucella abortus in bulls of the Amazônia-cerrado econtone

Abstract

Brucellosis and Leptospirosis play a particularly significant role when present in cattle herds, as they can adversely affect the reproductive performance of the herd, therefore causing direct and indirect losses. Because bulls can mate with many cows, they can spread these diseases throughout the herd. It is therefore important to assess the reproductive health status of the herd. The purpose of this study was to identify the frequency of anti- Leptospira spp. and anti-Brucella abortus antibodies in bulls in the microregion of Araguaína, as well as identify the contributing factors for the occurrence of such diseases. Samples were taken from 165 breeding bulls from ten rural producers in eight cities of this microregion. They underwent andrological examination and standard serological tests to diagnosis B. abortus (AAT) and Leptospira spp. (SAM). Among bulls that underwent B. abortus (AAT) and Leptospira spp. (SAM) tests, 98.1% were considered to be fit for reproduction. Among the 165 breeding bulls that underwent SAM testing, 67.3% (111) were serum-reagent for at least one Leptospira spp. serovar, and Hardjo and Wolffi serovars were more frequently found. None of the animals displayed serological findings for B. abortus as a result of AAT. Among the sampled bulls, the frequency of anti-Leptospira antibodies in tested bulls was high, but none of the animals tested positive for B. abortus, this result was associated with the use of PNCEBT by the producers surveyed. As for the predisposition elements assessed, only herd size was considered to be significant, with a 2.32 fold increase in the likelihood of occurrence of leptospirosis in farms with more than 1,000 animals.