Studies on Adeno Viruses Infection Associated with Inclusion Body Hepatitis Hydropericardium Syndrome in Broiler Chickens

Abstract

Recently, 50 Egyptian broiler farms at different localities with a history of poor performance and variable deaths have been screened for presence of FAdVs. Macroscopically, the diseased birds showed hydropericardium, enlarged friable livers with ecchymotic hemorrhages, and varying mortality rates 1 to 7.5 % while, the most conspicuous histopathological lesions were severe diffuse necrotizing enteritis, hepatitis, pericarditis, and diffuse lymphoid depletion of the spleen. To identify FAdVs, liver tissues and cloacal swabs samples from all the flocks were examined using conventional polymerase chain reaction (PCR) with specific primers targeting hexon gene. The partial genome sequencing of the PCR product of FAdVs hexon revealed two types of FAdVs (type D and type E). The detected FAdVs type D (FAdVs-2, FAdVs-11) and FAdVs-E 8a were grown, titrated on CEL and utilized to infect three commercial broiler groups by oral inoculation at one day old for detecting the pathogenicity of these FAdVs isolates and their ability for induction of similar clinical symptoms and pathological lesions as those observed in filed condition. The experimentally infected groups displayed the similar pattern in field flocks with varying degrees of total fatalities percentages of 12, 16, and 6% in G1-G3 infected commercial broiler groups, respectively. Both FAdV-D 2,11 and FAdV-E 8a were determined to be primary agents causing economic losses in broiler