The Preparation Of The DNA Probe Of Chicken Inclusion Body Hepatitis Virus And Its Epidemiological Investigation

Inclusion body hepatitis (IBH) associated with fowl adenovirus (FAdV) infection has a worldwide distribution. Inclusion body hepatitis (IBH) is an acute disease, mainly occurring in young chickens (3-7weeks of age) and caused by several serotypes of fowl adeno-virus. The epidemiological studies on the field outbreaks of IBH indicated that most of the field outbreaks were found in association with other disease conditions that resulted in high mortality. FAdVs that infect mostly chickens are classified in the genus Aviadenovirus under the family Adenoviridae, and are further classified into five species and12serotypes. There are10serotypes related to inclusion body hepatitis of natural outbreaks at least. Serotypes cited IBH are mainly type2,3,4,5,6,7and type8. Natural outbreaks of IBH are characterized by a sudden onset of mortality, peaking after3-4days post infection (dpi), which usually returns to normal at5dpi, but occasionally continues for2-3weeks. Morbidity is low and sick chickens adopt a crouching position with ruffled feathers. The main lesions of IBH are pale, friable and swollen livers. Petechial or ecchymotic haemorrhages may be present in the liver and skeletal muscles. Basophilic or eosinophilic intranuclear inclusion bodies (INIBs) are often observed in degenerate hepatocytes.Culture standard strains of serotypes by chick embryo yolk sac inoculation. Design seven pair of primer according to the conserve sequence of Hexon gene of Serotypes3、5、6、7、9、10、11and gene sequences of low homology between the seven serotypes from NCBI GenBank, the proliferative virus through DNA extraction and PCR amplification. Then, through the retrieve of the target production from the gelatin, purification of the nucleic acid and fixed quantity, and then labeled it by digoxin kit, The labeled probe shows favorable sensitivity and specificity, The sensitivity assay indicates that the minimum content for detection is1pg and the specificity assay shows no cross reaction, and then detect some lesion liver tissue from some region of Shandong and jiangsu province by dot blot hybridization, All parts can detected positive disease chicken.According to the research, and compared with the other five serotypes, we can see the widespread of the pathogen of IBH. The popular serotype is mainly serotype2、3、4、5、6、7、 8. The system of the dotblot hybridization by the digoxin labeled probe is showing well availability. It is likely to be usedin the breed industry and laboratory diagnosis.