Prevalence and molecular characteristics of fowladenovirus serotype 4 in eastern Saudi Arabia

Abstract

IntroductionFowl adenoviruses are a diverse group of viruses affecting chickens. They belong to the genus Aviadenovirus in the family Adenoviridae (1). Currently, there are 12 known serotypes of fowl adenoviruses (2). Fowl adenovirus serotype 4 (FAdV-4) belongs to group I and is classified as a member of group C fowl adenoviruses according to restriction fragment length polymorphism (RFLP) (3). FAdV-4 is one of the newly emergent serotypes in many regions worldwide. It was reported in Angora Goth close to Karachi in Pakistan for the first time (4). Clinically, FAdV-4 causes several syndromes in the affected chicken populations such as inclusion body hepatitis and hepatitis-hydropericardium syndrome (5,6). The affected chickens show depression, ruffled feathers, and resting on the ground with their chest close to death (5). Necropsy examination reveals several changes in the liver, such as mottling and being large and pale. Sometimes ecchymotic hemorrhages and multifocal necrotic areas in the parenchyma of the liver are found (7). The clinical picture of FAdV-4-induced hydropericardium syndrome is characterized by the accumulation of jelly-like amber viscous fluid in the pericardial cavities of the affected birds. The infected hearts appear large, flappy, and rounded (7). It is not an easy task to diagnose FAdVs due to the existence of a large number of serotypes. This is in addition to the presence of a heterogeneous population of antibodies against different adenoviruses in the sera of apparently healthy birds. However, the combination of polymerase chain reaction (PCR) and RFLP patterns is one of the most recent trends for the identification of FAdV-4 (8). According to the International Committee of Taxonomy and Nomenclature of Viruses (ICTV), FAdVs were classified into 12 serotypes. Further classification based on RFLP digestion patterns classified them into five groups (A-E) (8,9). Several outbreaks were reported in many Asian countries such as Iraq, India, Japan, and many other countries (10-12). Despite the detection of FAdV-4 in Kuwait (10), nothing is known about its prevalence in the other Gulf countries, especially Saudi Arabia.Several breeder farms reported high morbidity and mortality rates in chickens around 15 weeks old. Birds in these farms showed typical hydropericardium syndrome. Necropsy examination showed that the affected hearts were Abstract: Fowl adenovirus serotype 4 (FAdV-4) is a new emerging viral disease of chickens worldwide. It causes inclusion body hepatitis and hepatitis-hydropericardium syndrome. Little is known about its prevalence in the Middle East. Here we report the prevalence of FAdV-4 in five chicken farms in eastern Saudi Arabia. High mortality rates were reported from birds from those five farms at 15 weeks of age. Gross examination revealed typical hydropericardium syndrome and accumulation of jelly-like materials in the pericardial cavities. We isolated FAdV-4 by using embryonated chicken egg inoculation. The inoculated embryos showed dwarfing, deformities, hemorrhage, an...

Isolation and characterization of fowl aviadenovirus serotype 11 from chickens with inclusion body hepatitis in Morocco

“…This result confirms the presence of FAdV in embyonated eggs. These results were similar to those reported by earlier workers [42,55]. In the present study, FAdV was successfully isolated in CEF cell cultures and in SPF embryonated eggs from the liver samples collected from affected chickens of the 3 flocks.…”

Pathology and Molecular Epidemiology of Fowl Adenovirus Serotype 4 Outbreaks in Broiler Chicken in Abu Dhabi Emirate, UAE

“…The FAdV infection has been described in several Asian and Middle East countries, including Saudi Arabia [22], Iraq [23], Pakistan [24,25], Korea [6], China [10], Japan [7] and India [26]. Most of these FAdV belong to FAdV-4, species C, a new dominant serotype worldwide.…”

Epidemiology, pathology, prevention, and control strategies of inclusion body hepatitis and hepatitis-hydropericardium syndrome in poultry: A comprehensive review

“…In addition, several reports of IBH and/or HHS were documented in Japan ( 31 ), Korea ( 32 ), India ( 33 ), Pakistan ( 34 ), Spain ( 25 ), Poland ( 35 ), Iran ( 36 ), Mexico ( 37 ), Brazil ( 38 ), Croatia ( 39 ), Australia ( 40 ), Greece ( 41 ), Iraq ( 42 ), Palastine ( 43 ), United Arab Emirates ( 44 ), Saudi Arabia ( 45 ), Morocco ( 46 ), and South Africa ( 47 ).…”