Chronic respiratory disease in chicken

Ascites syndrome is a common non-communicable disease in broilers. It mainly occurs in 20 Mel 40-day-old fast large broilers, characterized by obvious stagnant water in the abdominal cavity, serious damage to the heart, lungs and liver, although the incidence is not high, but the mortality rate is close to 100%.

The etiology of the disease has a variety of pathogenic factors, including not only the physiological and anatomical characteristics of broilers, but also environmental factors and pathogens of secondary infection after poisoning. Generally speaking, the factors that lead to hepatic portal vein circulation disturbance and right heart failure can lead to ascites.

Growing too fast. Because of the fast growth rate, the lung volume of the fast broiler is not proportional to the increase of body weight. in order to meet the body's need for oxygen, the pulmonary artery pressure increases and the blood flow increases, which aggravates the burden of the heart and leads to the hypertrophy and dilatation of the right ventricle. and then cause lung congestion, resulting in a large number of ascites.

The special physiological and anatomical characteristics of chicken. The lungs of chickens are fixed in the chest, and the range of oxygen exchange in pulmonary capillaries is not sufficient, which also causes pulmonary hypertension and pulmonary congestion.

Poisoning. Because the feed contains toxic oil or salt, sulfonamides and so on, poisoning can directly damage the liver, cause liver disease, and cause a large amount of ascites retention.

Hypoxia, cold, poor ventilation and other environmental changes lead to a decrease in the concentration of oxygen in the blood, the heart beats faster, resulting in cardiac dysfunction, and systemic congestion, especially liver congestion.

Seasonal infection of avian aspergillosis, colibacillosis, salmonellosis and other secondary pathogenic bacteria or some viruses cause lung, heart and liver lesions, resulting in a large number of ascites.

The clinical symptoms of the sick chicken walk slowly, in the shape of a duck, and in severe cases, it is difficult to stand, landing on the abdomen, showing the shape of a penguin, and the abdomen is obviously dilated in dark red or cyan. Palpation has obvious fluctuation, dishevelled feathers, lethargy, shortness of breath, cyanosis of chicken crown and beard, and diarrhea in some diseased chickens.

Pathological changes there are a large number of brownish red or khaki ascites in the abdominal cavity, sometimes clear, sometimes mixed with fibrin clots, liver swelling and congestion, sometimes perihepatitis, pericardial effusion, myocardial softness, obvious dilatation of the right ventricle and thickening of the wall. due to ascites oppressing liver swelling and congestion.

According to the causes of the disease, corresponding countermeasures should be taken:

Before 1.2 weeks old, the protein and energy in the feed should not be too high.

two。 Control the light, take 23 hours of light and 1 hour of dark feeding method regularly.

3. Reduce the feeding density, and it is forbidden to feed mildew and spoiled feed.

4. Do a good job in the environmental hygiene inside and outside the chicken house, disinfect the chickens in the house on time, pay attention to ventilation in the house, remove ammonia and carbon dioxide, and increase oxygen.

5. The diseased chickens should be properly restricted or reduced the energy level in the feed and treated with corresponding drugs, the excessive amount of vitamin C (600 g / ton) was added to the feed for 7 days, and half a month later, the normal amount of 5 Mel was used for 7 days, and the electrolyte balance was adjusted, drinking water with Wechsler vermin for 4 days, and Baotong kidney was used in the evening. To treat the primary disease of chickens, antibiotics or antiviral drugs should be used in time according to the incidence of the disease.

In the past, ascites in broilers was ignored as a symptom of other diseases, but in recent years, with the rapid promotion of large broilers, the disease is more and more likely to occur alone. As a non-communicable disease, the harm to the industry has become increasingly serious. Therefore, the breeding industry should pay enough attention to the disease. The occurrence of the disease is largely related to poor ventilation in the chicken house, but the problem of heat preservation in the house must be solved during ventilation.