The source of infection of chronic duck respiratory disease in ducklings is diseased ducks and infected ducks. When the air is contaminated, it is often transmitted through the respiratory tract, and can also be transmitted vertically through contaminated eggs. The ducklings are bred after hatching. If the temperature of the broiler house is too low, the air is cloudy, the breeding density is too high and the stress is very high. This can easily lead to the occurrence of this disease.
Clinical symptoms
At the beginning of the disease, one or both of the infraorbital sinuses may be swollen to form a raised bulge, which has a fluctuating feel. As the course of disease progresses, the swollen part becomes harder, the nasal cavity becomes inflamed, and serous or mucous secretions flow out from the nostrils. Diseased ducks often shake their heads; Some sick ducks accumulate slurries or mucus secreted in the eyes, and those with longer duration of disease have blind eyes. The sick ducks die less often and self-heal, but their growth and development are slow, and the meat quality is reduced. Egg production rate decreased. The necropsy of the duck in the subdiaphragmatic sinus is usually filled with serous or mucous secretions, the sinus mucosa is hyperemia, and some of them accumulate a large amount of necrotic cheese-like material; the airbag wall is cloudy, swollen and thickened; there is a conjunctival sac and nasal cavity Viscous secretions.
Prevention
1. Strengthen the feeding and management of the ducks in the house feeding period, and do a good job in house cleanliness, cold insulation, ventilation and air exchange, and prevent the ground from excessive humidity and excessive breeding density.
2. The duck farm implements the “all-in, all-out†system, and it is strictly sterilized with a 1:100 fungicide. Daily strict quarantine, timely elimination of sick ducks or isolation of fattening.
3. Newborn ducklings in affected areas can be treated with drugs.