Abstract
Background: Newcastle disease virus (NDV) causes a highly contagious and devastating disease in poultry, Newcastle disease (ND), which is particularly characterized by extensive pathologies in the digestive, respiratory and nervous systems. ND cause heavy economic losses to the world poultry industry by decreasing growth rate, decrease egg productions, mortality and morbidity. Although, significant advances have been made in the vaccine development, but outbreaks are reported in vaccinated birds leading decrease growth rate. Methods: In this study, we report the damage caused by the NDV infection in the pancreas of vaccinated as well specific pathogen free chickens. Results: The histopathological examination of the pancreas showed sever damage in the form of partial depletion of zymogen granules, acinar cell vacuolization, necrosis, and apoptosis, congestion in the large and small vessels, sloughing of epithelial cells of pancreatic duct, and mild perivascular edema. Increased plasma levels of corticosterone, somatostatin, were observed in NDV infected chicks at 3 and 5-day post infection (DPI). Slight decrease in the plasma concentrations of the insulin were noticed at 5 DPI. Significant changes were not observed in the plasma levels of glucagon. Furthermore, NDV infection has decreases the activity and mRNA expression of amylase, lipase, and trypsin from the pancreas. Conclusion: Taken together, our findings highlight that NDV induces extensive tissue damage in pancreas, decrease the activity and expression of pancreatic enzymes and increase plasma corticosterone and somatostatin.
Antibody response, viral load, viral clearance and growth rate in Tanzanian free-range local chickens infected with lentogenic Newcastle disease virus
