Prevalence of Porcine Circovirus Type 2 (PCV-2) in Smallholder Pig Farms in Thung-Yai, Nakhon Si Thammarat, Thailand

Abstract

Porcine circovirus type 2 (PCV2), which is a member of the Circovirus genus in the family of Circoviridae, is a small non-enveloped, closed-circular ssDNA. The PCV2-associated disease is one of the most important infectious agents on pig productivity worldwide, including China, India, Malaysia, and Thailand. It caused 2 major syndromes; postweaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS). In addition, PCV2 may cause complexity with a pathogenic agent into porcine circovirus associated diseases (PCVADs). This study aimed to determine the prevalence of PCV2 in smallholder farms in Thung Yai district, Nakhon Si Thammarat, Thailand. A cross-sectional study was performed; 100 blood samples were collected from 13 smallholder pig farms. The samples were classified into 4 groups based on the pig’s age; gilts, 6 sows, nursery-to-starter, and from growing to finishing pigs. Blood samples were carried out for DNA +extraction and nested-PCR. The epidemiological study showed 9 % positive by genetic detection. The result suggested that growing-to-finishing pigs had significant PCV2 infection, followed by nursery-to-starter pigs and sow groups. In addition, multiple farms showed a high positive and significant correlation (Cr ≈ 0.245). These results reveal a low prevalence of PCV2 in endemic regions in southern Thailand, which may help in the local control evaluation and eradication programs. Furthermore, the phylogenic study of local strain should be investigated for the occurrence of PCV2 genetic evolution in Thailand and neighboring countries.