Chicken infectious anemia-symptoms

Under natural conditions, the incubation period of this disease is not very clear, but the earliest 12 days can show clinical symptoms, the third to fourth weeks death increased. Anaemia and pathological changes of tissues appeared 8 days after artificial infection of 1-day-old chicks, and the disease began from 10 to 14 days, and then died.

Anemia is a characteristic symptom of the disease. The anemia of infected chickens was most serious 14 - 16 days after infection, and the hematocrit value dropped below 20%. Infected chickens show anorexia, depression, weakness, emaciation, weight loss, pale beaks, whiskers and visible mucous membranes, subcutaneous and muscle bleeding, and bleeding from wing tips is also very common. The number of red blood cells and white blood cells decreased to 109/L and 5×106/L respectively. A large number of chickens died 5 days to 6 days after infection, and the mortality rate was usually less than 30%. The chickens survived 20 days to 28 days after infection gradually recovered to health, but most of them grew slowly and became stiff chickens. If secondary bacterial, fungal or viral infection, can aggravate the disease, hinder recovery, death increased.

CIAV can cause immunosuppression, so infected chickens often secondary Clostridium perfringens and Staphylococcus aureus infection, causing gangrenous dermatitis of muscle and subcutaneous tissue; also can make chickens to Escherichia coli, inclusion body hepatitis adenovirus, infectious bursal disease virus, Marek's disease virus and reovirus and other pathogens susceptibility increased. In some flocks, a second death peak occurred two weeks after the first death peak, which was often caused by secondary infection in addition to horizontal transmission.