Caracterização epidemiológica de agentes virais em caprinos leiteiros no Semiárido da Paraíba, Nordeste do Brasil.

Abstract

The aim of this survey was to determine epidemiological indicators to viral infections in dairy goats in the semiarid region of the Paraíba State. It was determined the prevalence of positive flocks (foci) and seropositive animals, as well as risk factors associated with the infections due to caprine herpersvirus 1 (CpHV-1), Pestivirus, bluetobgue virus (BTV) and small ruminants lentivirus (SRLV) were identified. From 1,034 to 1,092 dairy goats were sampled in 110 dairy flocks in the county of Monteiro, Cariri Ocidental microregion, Paraíba State, during November 2009 to August 2011. To each disease the serological diagnosis was carried-out using internationally consolidated techniques. For SRLV the direct detection of the agent was performed by real-time PCR in blood and milk. A flock was considered positive when presented at least one seropositive animal. Prevalences of positive flocks were 89.1%, 6.36%, 59.1% and 44.6% for the infections by CpHV-1, Pestivirus, BTV and SRLV, respectively. Prevalences of seropositive animals were 36.6%, 0.82%, 12.1% and 8.1%, respectively. The use of natural mating was identified as a risk factor associated with CpHV-1 flock-level prevalence; for Pestivirus, not perform vermifugation and to perform umbilical cord cutting and disinfection were identified as risk factors; daily milk production upper to 19 liters was identified as risk factor to LA; for SRLV, umbilical cord cutting and disinfection and existence of good quality fences were identified as risk factors, and real-time PCR using white blood cells had a good performance, with sensitivity of 100%, specificity of 92.86%, concordance of 93.75% and Kappa index of 0.765. Based on the risk factor analysis it was possible to recommend measures and interventions aiming the minimization of economic losses.