Fowl Adenoviruses Type 8b Isolated from Chickens with Inclusion Body Hepatitis in Japan

Identification of specific serotypes of fowl adenoviruses isolated from diseased chickens by PCR

“…FAdV is classified into 12 serotypes, but the serotype associated with the disease in chickens is limited recently. We previously described the specific types that were isolated in recent FAdV-associated outbreaks in chickens [8,9,10]. We found that type 1 FAdVs were isolated most frequently from chickens diagnosed with GE and type 2 FAdVs were predominantly associated with cases of IBH.…”

“…Gizzard erosion (GE), inclusion body hepatitis (IBH), and hydropericardium syndrome (HPS) are diseases of chickens that result from infection with FAdVs [2,17]; serotypes 1, 8a and 8b were isolated from chickens with GE, serotypes 2, 8a and 8b from chickens with IBH, and serotype 4 from those with HPS [1,3,16]. Epidemiologic analyses focused on FAdVs isolated from chickens with clinical signs suggestive of IBH, GE and HPS have recently been reported [8][9][10]; tendencies similar to these have been confirmed in Japan.…”

“…The reference strains of each of the serotypes of FAdV as defined by Kawamura [6] were used in this study, including Ote (serotype 1), SR-48 (serotype 2), SR-49 (serotype 3), KR-5 (serotype 4), TR-22 (serotype 5), CR-119 (serotype 6), YR-36 (serotype 7), and TR-59 (serotype 8a) [5]. The TR-630 strain, which was isolated from chickens with IBH in 1972 [11], was identified as serotype 8b by sequence analysis of the gene encoding the virus hexon protein [11]. We also tested our assay on field FAdV isolates that were collected as part of routine virological diagnosis between the years 1996 and 2019; these are listed in Table 1.…”

“…Appropriate diagnosis is critical, as IBH outbreaks continue to present problems in Japan [9,11]. Type 2 (SR-48 type) viruses have been the major isolates from chickens diagnosed with IBH since 2009 in Japan [14]; however, since 2018, the isolation of type 8b (TR-630 type) in association with IBH has been increasing [11].…”

A 10-Year Retrospective Study of Inclusion Body Hepatitis in Meat-Type Chickens in Spain (2011–2021)

“…In the last two decades, a growing number of IBH outbreaks due to FAdV-2, -8a, -8b, and -11 have been reported worldwide [1,[6][7][8][9][10][11][12][13][14][15]. In Spain, a sharp increase in the number of IBH outbreaks in broiler and broiler breeder pullet flocks has occurred since 2011.…”