Deputy chicken haemophilus (HPG) profile

Deputy chicken Haemophilus (Haemophilus paragallinarum, HPG) is the pathogen of chicken infectious rhinitis, pasteurella Haemophilus genera. The bacteria on both ends obtuse, without flagella and capsule, belonging to the facultative anaerobic bacteria. Under the condition of proper nutrition, can form the dew on the AGAR medium small colony, no hemolysis. Deputy chicken haemophilus have multiple serotype, usually divided into A, B, C three, there is no cross reaction between them. Because the vice chicken haemophilus has different serotype, so its epidemiological characteristics and pathogenic are also different.

Pathogenic characteristics

Deputy chicken haemophilus morphological characteristics of the performance on both ends of the thick dyed form, no capsule and flagella, size is about 0.3 to 0.5 microns. To good in 5% of the carbon dioxide environment to grow, and can form on blood AGAR medium gray rounded colony, the surface is smooth, slightly raised, and hemolysis phenomenon. And staphylococcus aureus cross inoculation can be observed the phenomenon of "satellite".

epidemic

Deputy chicken haemophilus disease is common across the globe, especially in the chicken populated areas and chicken larger countries, the disease caused a great loss to poultry industry. Deputy chicken in different regions and countries, the prevalence of haemophilus and serotype distribution is also different. In China, for example, type A pair of chicken haemophilus are common, and type B in some areas has become A major epidemic strain.

Route of transmission

Deputy chicken haemophilus mainly through the respiratory tract infection, can also be spread through contaminated feed and water through the digestive tract. Sick chickens and recessive chicken pathogen were the main source of infection, the bacteria can spread by droplets and dust from the secretions to healthy chickens.

clinical signs and symptoms

Vice chicken chicken of haemophilus infection usually show depression, loss of appetite, reduce the water, and in the nasal cavity and sinus appear a large number of serous or mucous secretions. Who got sick chicken may persist or frequent sneezing, meat and face beard may be edema. If inflammation spread to the lower respiratory tract, may appear dyspnea, cough, shortness of breath. After layer chicken infection, usually show the egg production and hatching rate decreased.

Pathological changes

In terms of pathological changes, deputy chicken haemophilus infection causes of nasal cavity and sinus mucosa acute catarrhal inflammation, mucosal hyperemia swelling, covered a lot of mucus. In serious cases, sinus and eye conjunctiva may appear caseating exudate. If infection spread to the lungs, it may trigger a fibrinous pneumonia. In the layer chicken, ovarian follicle hyperemia, hemorrhage and deformation may occur.

Diagnostic methods

Deputy chicken haemophilus disease diagnosis relies mainly on the detection of bacteriology and serological test. Commonly used detection methods include bacteria cultivation, separation of bacteriology and drug sensitive test. Serological tests include serum plate agglutination test (SPA), hemagglutination inhibition test (HI) and enzyme-linked immunosorbent assay (ELISA).

Prevention and control measures

In order to control the vice chicken haemophilus disease, Suggestions to take comprehensive measures, including improving breeding management, to improve environmental health, reasonable ventilation and heat preservation, and the use of disinfectant to clean the henhouse and drinking water. In the onset of chickens, should be under quarantine treatment, and implement drug treatment for the whole chickens, the commonly used antibiotics including erythromycin, terramycin, etc. Vaccination is important means of prevention, can use a multivalent inactivated oil vaccine immunization, to stimulate the protective antibody according to different serotype.

conclusion

To sum up, deputy chicken haemophilus is a kind of important poultry pathogens and their infection causes the chicken infectious rhinitis, and may cause severe economic losses. Understand its pathogenic characteristics, epidemic situation, route of transmission, and clinical symptoms is vital for effective control and treatment of the disease. Through reasonable breeding management and scientific prevention and control strategies, the occurrence and impact of Haemophilus parachicken disease can be greatly reduced.