Risk factors associated with Leptospira sp. seroprevalence in goats in Northeast of Brazil.

Goat farming is of great importance for agriculture in Northeast of Brazil, which owns more than 90 % of the national herd, however, most studies on leptospirosis in goats in this region are local surveys with unplanned sampling. Thus, the objective of this study was to determine the factors associated with the seroprevalence of leptospirosis in goats in Northeast region of Brazil. Blood samples were collected from 4121 goats from 222 herds, belonging to the states of Ceará, Paraíba, Piauí , Rio Grande do Norte and Sergipe. Serological diagnosis was carried out using the microscopic agglutination test (MAT). In 82.9 % (95 % CI = 77.3-87.2 %) of the herds there was at least one animal seropositive for at least one of the serogroups of Leptospira sp., and 18.73 % (95 % CI = 17.5-19.9 %) of the animals were seropositive. Antibody titers ranged from 100 to 800 and the most frequent serogroups were Autumnalis (23.06 %) and Australis (20.98 %). According to the robust Poisson regression analysis, four factors were associated with seroprevalence: animal sex (female) (P = 0.040), educational level of the farmer (elementary school) (P < 0.001), contacting institution for technical support (P = 0.040) and presence of irrigation area (P = 0.002). There was a high frequency of Leptospira sp. in goats in the states of Northeast region of Brazil, and it's suggested the need for better technological and preventive assistance of herds.