Occurrence of antibodies against Herpesvirus and Arteritis Virus in equines from the state of Rio Grande do Norte, Brazil

ABSTRACT

Background: Equine Herpesvirus type 1 (EHV-1) and Equine Arteritis Virus (EAV) have a high capacity for dissemination, causing losses in horse breeding due to reproductive, respiratory and neurological problems. In the State of Rio Grande do Norte there is only one survey, in the municipality of Mossoró, about these diseases. The purpose of this study was therefore to determine the prevalence and assess the risk factors associated with EHV-1 and EAV infections in unvaccinated horses raised in the mesoregions of East and West Potiguar in the State of Rio Grande do Norte, Brazil. Materials, Methods & Results: Between August 2018 and February 2019, blood samples were collected from equines on farms located in sixteen municipalities in the mesoregions of East and West Potiguar for the serological diagnosis of EAV (809 samples from 90 farms) and of EHV (778 samples from 88 farms), being that, only municipalities that had at least five hundred equines were included in the study. An investigative epidemiological questionnaire was applied to each property visited, containing questions related to the breeder, property, animal and the sanitary, reproductive and nutritional management. A logistic regression was performed to assess the risk factors associated with EVH, considering the serological test (positive or negative) as the dependent variable. EAV and EVH antibodies were detected through the serum virus neutralization assay. No evidence was found of EAV [0% (0/809)], but EHV showed a prevalence rate of 32% (249/778), with 80.6% (71/88) of the farms having at least one animal that tested positive, and EHV was present in all the municipalities covered in this study. The risk factors identified were animals raised in East Potiguar (OR = 1.36, CI 95% 1.01-1.85, P = 0.041), extensive livestock farming system (OR = 1.79, CI 95% 1.10-2.91, P = 0.041), working animals (OR = 3.63, IC 95% 1.91-6.91, P =...