Detection and characterisation of porcine circoviruses in wild boars in northeastern Serbia

The objective was to expand and update the knowledge on the presence and genotype diversity of porcine circoviruses 2 and 3 (PCV2 and PCV3) in the wild boar populations from the hunting grounds in northeastern Serbia. The presence of PCV3 was not determined, and PCV2 was confirmed in 40.32% of the organ samples from 124 wild boars hunted from 2018 to 2019, indicating their significance in virus circulation since traditional pig farms with irregular PCV2 vaccination strategies are widespread in this region. The most prevalent genotype was PCV2d, followed by PCV2b and PCV2a in 55.6%, 38.9%, and 5.5% of the examined samples, respectively. Nucleotide sequences of the detected strains were homogenous within the genotype and clustered within the sub -group s PCV2d-2, PCV2b-1A/B, and PCV2a-2D with high identity to European, Chinese, and Serbian domestic pig sequences suggesting their origin. Wild boars presented with no clinical or pathological signs of infection, implying that these animals might be less susceptible to disease, particularly since the cofactors present in pig farming systems that support the disease development are absent in the wild. The high PCV2 detection frequency demonstrates the importance of wildlife monitoring to track virus population dynamics, especially in regions with fre e-range pig farming in order to plan adequate disease control strategies.

Automated summary

The study aimed to expand knowledge on the presence and genetics of PCV2 and PCV3 in wild boar populations in northeastern Serbia. PCV3 was not found, but 40.32% of organ samples from wild boars hunted between 2018 and 2019 tested positive for PCV2, indicating its significance in virus circulation. The most prevalent genotype was PCV2d, followed by PCV2b and PCV2a. Wild boars showed no signs of infection, suggesting they may be less susceptible to the disease. Monitoring wildlife is important for tracking virus dynamics in regions with free-range pig farming.