The Effect of Beak and Feather Disease on Cellular Proportion and Functioning

Beak and feather disease (BFD) is a highly contagious viral disease, caused by the beak and feather disease virus (BFDV), and known for its rapid spread through avian populations. Infected individuals often exhibit weakened feathers and brittle beaks, severely impairing their ability to forage and survive. BFD significantly affects leukocyte concentrations while also disrupting mitochondrial function, further compromising the immune response, and deteriorating the overall health of infected birds. While certain species, such as P. elegans, exhibit a remarkable ability to harbour the virus while displaying minimal visible symptoms, their infection status actively contributes to the high prevalence of BFD in avian populations. To explore the relationship between BFDV infection and immunocompetence, the heterophil-to-lymphocyte (H:L) ratio and absolute white blood cell counts (WBC) were used. The study aimed to investigate the viral impact on mitochondrial function by using a novel technique to assess the effects of BFDV in frozen samples. Additionally, the potential associations of BFDV with body condition, sex, age, and breeding status in infected individuals were examined to determine the presence of a significant correlation between these variables. The findings did not reveal significant relationships between BFDV infection and any of the measured factors. This suggests that BFDV may exhibit a unique pattern of interaction with its avian hosts, possibly by exploiting the host?s immune responses or utilising alternative mechanisms to persist within populations. Further research is necessary to elucidate the underlying mechanisms governing the interactions between BFDV and its avian hosts and to better understand the implications for disease spread and management strategies.