Molecular detection of Leptospira spp. in goat's milk produced in a semiarid region

Abstract

Brazil has a large flock of goats, and in the Northeast, there are around 94.5 % of the total flock, highlighting the states of Bahia, Ceará, Pernambuco, Piauí and Paraíba. Dairy goat farming based on the development of alternative models instigates the generation of income, the creation and strengthening of rural micro-enterprises linked to credit programs, aiming to reach quality in the products for the regional consumer market. Infectious diseases, such as leptospirosis, highlights regarding the drop in productivity, and, for detection of this agent, PCR (Polymerase Chain Reaction) is used as a direct diagnosis method. In the present work, molecular tests were carried out in 189 goat milk samples, collected in the dry period of 2019, from flocks of four municipalities in the backlands of Paraíba state, Brazil, five samples of collective cooling tank milk and four pasteurized milk samples. The primers LipL32-45F and LipL32-286R were used to amplify the gene LipL32, specific to pathogenic leptospires. The PCR technique detected the agent's DNA in 146 (77.24 %) goat milk samples; from collective tank, all five samples (100 %) showed Leptospira spp. DNA, so like the four pasteurized milk samples. The presence of leptospires in the mammary gland in lactating females is associated with the bacteremia phase of the infection, leading to a potential zoonotic risk in the consumption of raw milk by humans. Therefore, the goat milk production chain must consolidate efforts to improve milk quality, through the implementation of more effective health control measures and hygienic milking for flocks, including the use of monitoring and control tools, such as Hazard Analysis and Critical Control Point (HACCP), at all stages of goat milk production.