Duck hepatitis-prevention and treatment

According to the characteristics of the disease, emphasis should be placed on environmental hygiene control and immunity to breeder ducks.

(1) Environmental hygiene control: the disease can be prevented by strict isolation. Ducklings under 4 weeks of age are susceptible to DHV, so isolated feeding of ducklings within 4 weeks of age to prevent DHV infection can effectively control the occurrence of DHV. Strict disinfection is an important measure to prevent the disease. Before each batch of duck fry enters the duck house, the duck house is sprayed with 5% sodium hydroxide solution and other disinfection measures. Once the disease breaks out, the duck house should be isolated immediately and thoroughly disinfected.

(2) Vaccine immunization

1. Attenuated vaccine: at present, many attenuated vaccine strains such as QL79, E52, CE81 and Fc are widely used. Immunization with attenuated vaccine includes two situations: (1) ducklings are immunized 2-4 weeks before eggs are collected and injected twice at intervals of 1 week. DHV antibodies are transmitted to ducklings through eggs. Ducklings can get maternal antibody protection after 2 weeks. The general immunization period is 6 months, and the second immunization should be considered after 5-6 months. (2) when 1-day-old ducklings were immunized with attenuated duck vaccine, 3d~7d could produce immunity, but maternal antibody could affect the immune effect, and it often occurred in production practice that the immune effect of ducklings was not exactly caused by the onset of disease, so it was not widely used in production.

2. Inactivated vaccine: if the basic immunization of attenuated vaccine has been carried out, the oil-adjuvant inactivated vaccine can induce ducks to produce high titers of antibodies, whereas the antibody level is very low. In some areas where the disease is seriously endemic and duck farms, breeder ducks are immunized with attenuated vaccine one month before production, and then enhanced with oil-adjuvant inactivated vaccine a week later, the next generation of ducklings can obtain higher titers of maternal antibodies.

At present, attenuated vaccine is widely used in production practice, while inactivated vaccine is seldom used because of its high price and long time of producing immunity.

(3) the use of specific antibodies.

1. For ducklings without maternal antibody protection, 0.5ml~1ml hyperimmune serum or egg yolk solution can be injected subcutaneously at the age of 1-2 days, which can effectively prevent the occurrence of DVH.