Symptoms of bird flu in chickens

For chicken farmers, avian influenza is the disease they fear the most, because we all know that avian influenza will directly affect the health of poultry. Sometimes, if it is serious, it will even cause the death of all the chickens. Therefore, it is necessary to do a good job of prevention. So do you know what symptoms chickens will show after contracting avian influenza? Find out now.

The problem of avian influenza will directly affect the growth of chickens, so in the face of this situation, chicken farmers must pay attention to it. As long as we know more about its symptoms, we can do a good job of prevention in time and solve and treat it in a targeted manner, so as to better reduce the damage.

The length of the incubation period of this disease varies greatly depending on the virulence of the virus that infects the poultry, the number of viruses, the route of infection, etc., ranging from a few hours to a few days. The disease types can be divided into three categories according to the symptoms and pathological changes of avian influenza in chickens: acute septicemia, acute respiratory type and atypical type. Acute septicemic avian influenza (typical avian influenza) The main symptoms of sick birds are extreme depression, lethargy, gasping with open mouth, runny eyes and nose (in waterfowl, pus-like fluid can sometimes be seen flowing out of the eyes and nose), cyanosis and bleeding of the crown and beard, swelling of the head and neck, and acute death.

Some cases present with neurological symptoms such as ataxia, tremor, head tilt, and neck twisting. The characteristic pathological changes are corneal opacity, conjunctival hemorrhage and ulcers; red and black patchy hemorrhages on the skin surface of wings and crop; calf hemorrhages (reddish-brown hemorrhagic patches on the calf scales) and edema are also common; subcutaneous edema (especially subcutaneous of the head, neck and chest) or gelatinous infiltration; lung hemorrhage and edema, grayish-white mottled necrosis of the spleen, brown mottled hemorrhage, degeneration and necrosis of the pancreas; bursal hemorrhage; bleeding and ulcers in the mucosa of the entire digestive tract from the mouth to the cloaca, or grayish-white spots and striped membranes (necrotic pseudomembranes); other tissues and organs may also have bleeding, and obvious fibrinous peritonitis and air sacitis are often seen. The myocardium of some sick chickens has grayish white necrotic stripes.

Acute respiratory avian influenza (typical avian influenza) The main symptoms of sick birds are runny eyes and nose, rapid breathing, coughing, sneezing, swollen sinuses, diarrhea, and some deaths (the mortality rate is higher when co-infected with Newcastle disease virus or other avian paramyxovirus type I strains). The main pathological changes are laryngeal and tracheal bleeding, accumulation of secretions in the sinuses, conjunctival edema and bleeding, and sometimes pathological changes similar to acute septicemic avian influenza are also seen. Atypical avian influenza: Sick birds generally show symptoms of tearing, coughing, panting, diarrhea, a significant drop in egg production (a drop of 50% to 80%), and sporadic deaths. The gross pathological changes are some exudative inflammation in the sinuses, trachea, air sacs, and intestines. Sometimes fibrinous exudates are seen in the air sacs, the cyst walls are thickened, yolk peritonitis occurs in the hens, and inflammatory exudates are present in the oviducts.

The above is an introduction to the symptoms of chickens infected with avian influenza. I hope that everyone can pay more attention to these symptoms in their lives. As long as we discover these phenomena in time, we can effectively help poultry to receive targeted treatment and reduce the harm of avian influenza to chickens.