Genetic Differences and Pathogenicity of Chicken Anemia Virus Strains in Broiler’s Baby Chicks

This study aims to molecular characterization of the Chicken Anemia Virus (CAV) in young broilers in the Giza governorate, Egypt in 2021, assess the genetic diversity among the proliferating viruses, and vaccine strains, and evaluate their pathogenicity to improve viral management. Viral protein 2 (VP2) gene was amplified and subsequently conducted molecular-level characterization. In five out of the ten flocks sampled CAV was detected. Furthermore, the examination of the phylogenetic connections performed according to the sequences of the VP2 gene demonstrated the classification of the observed field strains within genogroups I, II, and IIIb. In silico analysis was performed on Cux-1 and the detected five strains to investigate the secondary structures of VP2 proteins. The findings indicated a significant resemblance in the distribution and quantity of α-helical and β-strand topologies. To assess the pathogenicity of the virus, two isolates from genotype III (MZ574096.1) and genotype II (MZ477000.1) were administered intramuscularly to sets of day-old, specific pathogen-free chicks. At 28 days following inoculation, the Red Blood Corpuscle count (X106µL) was (1.4 ±0.39 and 1.8± 0.12).