Characterization of Fowl Adenoviruses from Outbreaks of Inclusion Body Hepatitis/Hydropericardium Syndrome in Chile

Abstract

Three fowl adenovirus (FAV) isolates (341, 344, and 215) obtained during 1996-97 from field outbreaks of inclusion body hepatitis/hydropericardium syndrome (IBH/HPS) affecting broilers and broiler breeders in Chile were characterized by virus neutralization tests (VNTs) and restriction enzyme analysis of a DNA fragment. Furthermore, the pathologic characteristics of one of these FAV isolates (FAV 341) was studied in experimentally infected chickens. The VNTs conducted with isolates 341 and 344 against reference strains and antisera belonging to each of 12 FAV serotypes demonstrated a close antigenic relationship with strain KR5 of the FAV serotype 4. Polymerase chain reaction using the primers H3/H4 and subsequent HpaII digestion was used for serotype identification of isolates 341 and 215. The length of the PCR products and the restriction profiles of isolates 341, 215, and the reference strain KR5 (FAV4) were identical. The present results confirmed the classification of all three isolates as FAV4. The pathogenicity test with 1000 mean tissue infectious dose of isolate 341 inoculated intramuscularly in 20-day-old specific-pathogen-free chickens resulted in the death of 9% (two birds) six days postinoculation (PI). Both birds showed characteristic IBH/HPS gross and microscopic lesions; the remaining birds, sacrificed at day 10 PI, showed less severe lesions. On the basis of epidemiologic and experimental data of the virulence of Chilean FAV isolates, and the pathogenicity results with isolate 341, we speculate that Chilean FAV strains may require an association with other agents (immunosuppressive agents) to induce IBH/HPS outbreaks in the field.

Investigation of Hepatitis-Hydropericardium Syndrome Caused by Fowl Adenovirus (FAdV) Infection in Broiler Chicken Flocks in Northern Parts of India

“…In the past two decades several disease outbreaks have been recorded from poultry flocks of different stares and regions of India, causing severe economic losses to the poultry owners and the industry (Dahiya et al, 2002;Gowthaman et al, 2012;Sawale et al, 2012;Kataria et al, 2013;Kumar et al, 2013). The presence of immunosuppressive disease conditions like infectious bursal disease (IBD), chicken infectious anemia (CIA) and mycotoxins prior to infection with FAdV are believed to be the predisposing factor in the pathogenicity of IBH-HPS syndrome (Toro et al, 1999;Toro et al, 2000;Shivachandra et al, 2003;Gowthaman et al, 2012;Hussain et al, 2012). However, several cases of IBH have been reported without any obvious immunosuppressive diseases (Hafez, 2011).…”

Pancreatic Necrosis and Ventricular Erosion in Adenovirus-associated Hydropericardium Syndrome of Broilers

“…6 HPS was induced by serotype 4 GIAAV. 5,10,14 The present virus isolate is also serotype 4 of GIAAV. Although serotypes of GIAAV are not always consistent with virus virulence, the prevalent GIAAV strain causing HPS may be the same serotype, serotype 4.…”

“…This suggests that GIAAV from HPS is more virulent than IBH. The previous reports of natural HPS [1][2][3]12,14 referred to hepatocytic necrosis with intranuclear inclusion bodies of hepatocytes, but did not report pancreatic necrosis or gizzard erosion. This virus strain may have different pathogenicity from previous virus strains of HPS.…”

“…This disease was reported subsequently in Iraq, 2 India, 12 Mexico, 8 Ecuador, 5 Japan, 1 and Chile. 14 Chicks affected with HPS had inclusion body hepatitis and serotype 4 of group I avian adenovirus (GIAAV) was isolated from livers. 1,5 GIAAV could experimentally produce mortality with HPS in broilers 3 and specific-pathogen-free (SPF) chickens.…”

Genetic Characterization of Fowl Adenoviruses Isolated from Chickens with Hydropericardium Syndrome in Japan

“…So far, HPS has been reported in Pakistan, Japan, Iraq, Kuwait, India, the former U.S.S.R. Chile, Mexico and Korea [1,2,7,9,11,13,19]. In Japan, the first outbreak of HPS was confirmed in Tokushima prefecture, in the western part of Japan, in 1996 [2].…”