Risk factors associated with lentivirus seroprevalence in sheep and goat herds from northeastern Mexico

Abstract

A cross-sectional study was conducted with the purpose of determinate the risk factors associated with the serological frequency of small ruminant lentivirus (SRLV) in sheep and goats from northeastern Mexico. From 128 herds, 71 of goats, 32 of sheep and 25 mixed herds (goats + sheep), 768 individual sera were collected from animals ≥1 yr old. From each herd, 4 to 5 serum samples were mixed and analyzed by ELISA to identify antibodies against SRLV glycoprotein 135. Samples were obtained from randomly selected animals in 2019 and 2020. A questionnaire was applied to the producers and the data were analyzed to determine the risk factors associated with herd seropositivity by logistic regression. The proportion of seropositive herds, overall, was estimated at 50.6 %. According to the type of herd, seropositivity in goat herds was 62.0 %, in sheep herds 25.4 % and 50.2 % in mixed herds. The risk factors associated with the presence of antibodies against SRLV were the presence of animals with arthritis, veterinary care, reuse of needles, nerve alterations, low pregnancy rate, type of herd and mastitis. Serological frequency indicates a high endemicity of SRLV in small ruminant herds from northeastern Mexico.