ABSTRACT
The prevalence of antibodies against bluetongue virus was investigated in 41 dairy goats and 40 sheep herds in the semi-arid region of Pernambuco state and the conditions for insect Culicoides maintenance, considering climate dynamics and vector competence, were evaluated. The percents of seropositive herds in agar gel immunodiffusion test for bluetongue virus group were 24 for goats and 27.5 for sheep. The estimated prevalences of seropositive animals were 3.9 percent for goats (n = 410) and 4.3 percent for sheep (n = 400). The prevalences of seropositive animals were low in the mesoregion of Sertão Pernambucano (4.8 percent for goats and 4.1 percent for sheep) and São Francisco Pernambucano (1.0 percent for goats and 4.5 percent for sheep). There were no significant differences between species and regions. Considering the social and economic importance of goats and sheep raising in the semi-arid region, it is essential to establish preventive measures to control imports of ruminants from these areas.