Abstract
Pestiviruses, particularly bovine viral diarrhea virus (BVDV), cause significant economic losses worldwide. While cattle are the primary hosts for BVDV, sheep and goats can also be affected. This nationwide survey aimed to assess the prevalence, genetic characteristics, and risk factors associated with pestiviruses in sheep and goats in Kazakhstan. A one-off cross-sectional study was conducted to estimate the prevalence of pestiviruses in sheep and goats across 58 districts in 17 oblasts of Kazakhstan. A total of 2028 animals were examined using antibody ELISA, and RT-qPCR was performed on 2056 samples. Logistic regression models were used to identify potential risk factors linked to pestiviral infection. The overall prevalence of pestiviral infection in small ruminants was estimated to be 53.7% by ELISA and 2.5% by RT-qPCR. Regression analysis revealed that age, farm type, and geographic location were risk factors for pestiviral infections in small ruminants in Kazakhstan. Partial sequence analysis of the 5'-untranslated region confirmed the presence of BVDV2. Phylogenetic analysis revealed two distinct clusters of Kazakhstani BVDV2 strains, which were significantly different from known BVDV2 genotypes. No other ruminant pestiviruses were identified. The results highlight the importance of integrating small ruminants into BVDV infection control strategies to mitigate risks to livestock.