Seroprevalence and risk factors for Leptospira spp. in small ruminants of semi-arid zone in northeastern Colombia.

Leptospirosis in small ruminants is an economically important disease that causes important losses by pathologies of the reproductive tract. The present study aimed to estimate the seroprevalence and risk factors associated with Leptospira spp. in small ruminants under traditional husbandry systems. A cross-sectional epidemiological study was carried out in a sample of 1039 animals which included 793 sheep and 245 goats from 49 farms of 10 municipalities of northeastern areas of Colombia. The MAT test using a panel of 13 laboratory serovars was performed to diagnose the Leptospira spp. antibodies in the serum samples of animals. A structured questionnaire was filled in each farm to obtain information on putative risk factors, and its association with Leptospira spp. infection was detected by univariate and multivariate logistic regression. The general seroprevalence showed a rate of 13.9%, the 79.6% of farms showed at least one positive animal, the 14.2% and 0.4% of positive animals showed titers ≥ 1:100 and 1:200, respectively. The seroprevalence in sheep and goats showed a rate of 13.1% and 16.2%, respectively. The most common serovars in positive animals were Autumnalis (3.6%), Tarassovi (3.4%), Bratislava (2.9%), Mini (2.9%), Bataviae (1.4%), Canicola (0.3%), and Grippotyphosa (0.3%). The univariate and multivariate analysis showed as risk factors the absence of housing system (OR = 3.412 CI: 1.347-8.152), the absence of quarantine measures to new animals (OR = 1.371 CI: 0.943-1.978), and the protective factor identified was the use of Toggenburg breed (OR = 0.571 CI: 0.249-1.074). This exploratory study showed the Leptospira spp. positive small ruminants located in the northeastern areas of Colombia with titer associated with chronic and subclinical infection.
(© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)