Biological and Genetic Characterization of a Bali Fowlpox Virus Isolates From Layer Chickens

Fowlpox is one of the most important viral diseases in poultry, causing significant economic losses particularly in layer chickens. This study aimed to characterize the biological and genetic properties of a fowlpox virus isolates from layer chickens in Bali. Using a descriptive exploratory approach, viruswas collected from cutaneous lesions of layer chickens in Penebel, Tabanan, Bali. Biological characterization included field clinical observation, virus propagation on the chorioallantoic membrane, histopathological examination of pock lesions, and cytopathic effect evaluation in chicken embryo fibroblast cell cultures. Genetic characterization used polymerase chain reaction targeting the P4b gene, followed by sequencing and phylogenetic analysis. The Bali isolate produced characteristic pock lesions on chorioallantoic membrane, induced epithelial hyperplasia and intracytoplasmic inclusion bodies (Bollinger bodies), and caused cytopathic effect in chicken embryo fibroblast cultures including cell swelling, aggregation, and monolayer destruction. Molecular detection confirmed the presence of fowlpox virus via P4b gene amplification (578 bp). Phylogenetic analysis showed the Bali isolate belongs to the fowlpox-like clade. Integration of biological and genetic approaches provided a comprehensive characterization of fowlpox virus isolates circulating in Bali, representing the first published scientific report of molecular characterization of fowlpox virus from Bali, Indonesia. Cite this article as: Saputri, R. L., Sari, T. K., Kencana, G. A. Y., Kardena, I. M., Suardana, I. B. K., & Astawa, I. N. M. (2026). Biological and genetic characterization of a Bali fowlpox virus isolates from layer chickens. Acta Veterinaria Eurasia, 52, 0157, doi:10.5152/actavet.2026.26157.