Inclusion Body Hepatitis Caused by Fowl Adenovirus in Broiler Chickens in Japan, 2009–2010

Abstract

From January 2009 to June 2010, many broiler chicks suddenly died without clinical signs. The mortality rates were from 1.2% to 17.0% in affected flocks. Inclusion body hepatitis (IBH) was detected in 13 prefectures (northern, eastern, western, and southern areas) in Japan. The livers were enlarged and pale. The bursa of Fabricius and thymus had not atrophied. Multifocal necroses of hepatocytes with basophilic intranuclear inclusions were seen in the liver. Eosinophilic intranuclear inclusion bodies in hepatocytes were rare. Focal necrosis of acinar cells with basophilic intranuclear inclusions was found in the pancreas. Basophilic intranuclear inclusion bodies were detected in intact surface epithelial cells of gizzard and epithelial cells of the small intestine. The intranuclear inclusions of liver, pancreas, gizzard, and small intestine were stained positively for immunohistochemistry of fowl adenovirus (FAV) antigen. Ultrastructurally, basophilic intranuclear inclusions consisted of viral particles approximately 70 nm in diameter and arranged in a crystalline array. FAV was isolated from the liver of chickens affected with IBH. The serotype of most isolates was 2. This study suggests that IBH produced by FAV is epidemic in broiler chicks in Japan and that the present cases occurred as the primary disease without the association of infectious bursal disease virus or chicken anemia virus.

Identification of four serotypes of fowl adenovirus in clinically affected commercial poultry co‐infected with chicken infectious anaemia virus in Trinidad and Tobago

“…Experimental infection of chickens with certain FAdV strains has demonstrated disease and mortality due to FAdV alone (Erny, Barr, & Fahey, 1991;Mazaheri, Prusas, Voss, & Hess, 1998;Saifuddin & Wilks, 1992). FAdV has also been found to be primarily responsible for field cases of severe clinical disease, where other viral agents were not found to be present (Gomis, Goodhope, Ojkic, & Willson, 2006;Nakamura et al, 2011).…”

Commensal or pathogen – a challenge to fulfil Koch’s Postulates

“…However, earlier reports about IBH in New Zealand had already indicated that IBH can be a primary disease which was confirmed in a series of more recent reports of IBH outbreaks in Canada, Australia and Japan (Christensen and Saifuddin, 1989; Gomis et al ., 2006; Nakamura et al ., 2011; Steer et al ., 2011). In addition, the prevalence of FAdV does not coincide with the presence of IBDV or CAV (Eregae et al ., 2014).…”

“…A larger number of IBH outbreaks were reported from Canada (Pettit and Carlson, 1972) and Iraq (Al-Sheikhly and Mutalib, 1979) based on histological diagnosis until the disease was reported from New Zealand (Saifuddin et al ., 1992) and Australia (Erny et al ., 1991), predominantly caused by FAdV-8. Single case reports were published until about 10 years ago when the number of outbreaks in geographically different areas worldwide increased substantially (Gomis et al ., 2006; Ojkic et al ., 2008 a , 2008 b ; Lim et al ., 2011; Nakamura et al ., 2011; Steer et al ., 2011; Choi et al ., 2012; Kaján et al ., 2013; Maartens et al ., 2015; Zhao et al ., 2015; Niczyporuk, 2016; Schachner et al ., 2016). …”

Epidemiological and pathological investigation of fowl aviadenovirus serotypes 8b and 11 isolated from chickens with inclusion body hepatitis in Spain (2011–2013)

“…In recent years, IBH outbreaks have been detected in different countries; serotypes 2, 4, 8a, 8b and 11 have been the most frequent serotypes involved (Grgic et al, 2011;Nakamura et al, 2011;Steer et al, 2011;Choi et al, 2012;Dar et al, 2012;Kajan et al, 2013;Joubert et al, 2014;Zhao et al, 2015;Schachner et al, 2016).…”