Symptoms and Prevention Methods of Ascites Syndrome in Broiler Chickens
Ascites Syndrome in Broiler Chickens
Ascites syndrome in broiler chickens, also known as "heart failure syndrome," is also called broiler pulmonary hypertension syndrome. It is characterized by an enlarged abdomen with a fluctuating feel on palpation, thinning and shiny abdominal skin, and severe redness in some cases. On necropsy, there is a large amount of pale yellow or clear transparent fluid in the abdominal cavity, sometimes mixed with fibrinous deposits; heart failure, pericardial effusion, and lesions of the liver and kidneys are characteristic features. It mainly occurs in broiler chickens. This disease not only has a relatively high mortality rate but also affects rearing profitability by lowering the slaughter grade of broiler chickens, causing great harm to broiler production. Because its causes and pathogenesis are complex, once it occurs, it is very difficult to control. At present, there is no specific therapy; only by targeting the causes and adopting comprehensive prevention and control measures can the occurrence of ascites and the losses it brings be reduced.
I. Causes:
Inherent factors
Fast-growing broiler chickens have relatively high requirements for energy and oxygen. The red blood cells of broiler chickens are larger than those of laying hens. Especially during the rapid growth period within 4 weeks of age, red blood cells cannot flow smoothly through the pulmonary capillaries, affecting pulmonary blood perfusion and leading to pulmonary hypertension and subsequent right ventricular failure.
2. Primary factors
1) Chronic hypoxia:
Broiler chickens raised in high-altitude areas suffer from thin air and low oxygen pressure. Broiler chickens raised in low-altitude and sea-level areas are kept in poorly ventilated houses, especially in winter when doors and windows are closed, and the concentrations of carbon dioxide, ammonia, carbon monoxide, and dust in the chicken house increase while oxygen pressure decreases, causing chronic hypoxia in the body, which in turn causes thickening and narrowing of the pulmonary capillaries and increased pulmonary artery pressure, followed by enlargement and failure of the right ventricle.
2) High-energy diets or pelleted feed:
Both high-energy diets and pelleted feed can increase the feed intake of broiler chickens, increasing the oxygen demand for energy expenditure and causing the disease.
3. Secondary factors
1) Nutritional stress:
Deficiency or excess of certain nutrients can cause secondary ascites on the basis of the primary disease, such as deficiency of selenium, VE, and VC, excess salt, etc. However, by the mid-1980s it was already clear that ascites is not caused by the deficiency of any single nutrient. In some experimentally affected flocks, no evidence of selenium or VE deficiency was detected, and adding VC and minerals to the feed also failed to reduce the occurrence of ascites.
4. Others:
Respiratory system diseases or airborne pollutants, etc., cause impaired pulmonary gas exchange function, which in turn causes increased pulmonary vascular blood pressure. It is generally believed that lung disease is the initial lesion of ascites pathology. In flocks affected by broiler ascites, almost no chicken has normally healthy lungs.
II. Pathological changes
1. Clinical symptoms
The disease presents as sudden death. Usually affected chickens are smaller than normal chickens, and have ruffled feathers and listlessness. Affected chickens are unwilling to move, and have difficulty breathing and cyanosis. The most obvious clinical sign visible to the naked eye is an enlarged abdomen in affected chickens, shaped like a water bag, with a fluctuating feel under pressure, and thinning and shiny abdominal skin. In severe cases, the skin becomes congested and red; some affected chickens have difficulty standing, rest on the abdomen in a penguin-like posture, move slowly, and walk with a duck-like gait. Abdominal puncture releases clear transparent pale yellow fluid.
III. Preventive measures
1. Improve feeding management
Broiler chickens grow rapidly in the early stage and are highly sensitive to ascites, so early feed restriction has a relatively obvious preventive effect.
First, the incidence of ascites in broiler chickens fed low-nutrition diets is far lower than in chickens consuming high-nutrition diets. It is recommended to feed a low-energy diet before 3 weeks of age and then switch to a high-energy diet.
Second, feeding mash feed can effectively control ascites in broiler chickens. In areas where broiler ascites is prone to occur, try not to add fat to broiler chicken diets.
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Are selenium, VE, and VC miracle drugs? Everyone says that adding these things can reduce the occurrence of disease.
Waiting for an answer.
--------------------------------------
When a disease occurs in a flock, adding vitamins as an auxiliary treatment measure plays a very important role, especially adding VA, Vc, and VK. Studies have shown that VE and Vc can enhance the body's immune function, improve the chicken body's tolerance to various stresses, and promote recovery after illness and growth and development. VK can shorten clotting time and reduce blood loss, so for some diseases with bleeding symptoms, it can alleviate symptoms and reduce deaths.
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It seems that adding some acidifiers to the feed can reduce the occurrence of ascites. Want to try?
--------------------------------------
Reply to 4#cheng_zhang
Okay, thanks for the suggestion. I hope the friends above also see your solution!
I. Causes:
Inherent factors
Fast-growing broiler chickens have relatively high requirements for energy and oxygen. The red blood cells of broiler chickens are larger than those of laying hens. Especially during the rapid growth period within 4 weeks of age, red blood cells cannot flow smoothly through the pulmonary capillaries, affecting pulmonary blood perfusion and leading to pulmonary hypertension and subsequent right ventricular failure.
2. Primary factors
1) Chronic hypoxia:
Broiler chickens raised in high-altitude areas suffer from thin air and low oxygen pressure. Broiler chickens raised in low-altitude and sea-level areas are kept in poorly ventilated houses, especially in winter when doors and windows are closed, and the concentrations of carbon dioxide, ammonia, carbon monoxide, and dust in the chicken house increase while oxygen pressure decreases, causing chronic hypoxia in the body, which in turn causes thickening and narrowing of the pulmonary capillaries and increased pulmonary artery pressure, followed by enlargement and failure of the right ventricle.
2) High-energy diets or pelleted feed:
Both high-energy diets and pelleted feed can increase the feed intake of broiler chickens, increasing the oxygen demand for energy expenditure and causing the disease.
3. Secondary factors
1) Nutritional stress:
Deficiency or excess of certain nutrients can cause secondary ascites on the basis of the primary disease, such as deficiency of selenium, VE, and VC, excess salt, etc. However, by the mid-1980s it was already clear that ascites is not caused by the deficiency of any single nutrient. In some experimentally affected flocks, no evidence of selenium or VE deficiency was detected, and adding VC and minerals to the feed also failed to reduce the occurrence of ascites.
4. Others:
Respiratory system diseases or airborne pollutants, etc., cause impaired pulmonary gas exchange function, which in turn causes increased pulmonary vascular blood pressure. It is generally believed that lung disease is the initial lesion of ascites pathology. In flocks affected by broiler ascites, almost no chicken has normally healthy lungs.
II. Pathological changes
1. Clinical symptoms
The disease presents as sudden death. Usually affected chickens are smaller than normal chickens, and have ruffled feathers and listlessness. Affected chickens are unwilling to move, and have difficulty breathing and cyanosis. The most obvious clinical sign visible to the naked eye is an enlarged abdomen in affected chickens, shaped like a water bag, with a fluctuating feel under pressure, and thinning and shiny abdominal skin. In severe cases, the skin becomes congested and red; some affected chickens have difficulty standing, rest on the abdomen in a penguin-like posture, move slowly, and walk with a duck-like gait. Abdominal puncture releases clear transparent pale yellow fluid.
III. Preventive measures
1. Improve feeding management
Broiler chickens grow rapidly in the early stage and are highly sensitive to ascites, so early feed restriction has a relatively obvious preventive effect.
First, the incidence of ascites in broiler chickens fed low-nutrition diets is far lower than in chickens consuming high-nutrition diets. It is recommended to feed a low-energy diet before 3 weeks of age and then switch to a high-energy diet.
Second, feeding mash feed can effectively control ascites in broiler chickens. In areas where broiler ascites is prone to occur, try not to add fat to broiler chicken diets.
--------------------------------------
Are selenium, VE, and VC miracle drugs? Everyone says that adding these things can reduce the occurrence of disease.
Waiting for an answer.
--------------------------------------
When a disease occurs in a flock, adding vitamins as an auxiliary treatment measure plays a very important role, especially adding VA, Vc, and VK. Studies have shown that VE and Vc can enhance the body's immune function, improve the chicken body's tolerance to various stresses, and promote recovery after illness and growth and development. VK can shorten clotting time and reduce blood loss, so for some diseases with bleeding symptoms, it can alleviate symptoms and reduce deaths.
--------------------------------------
It seems that adding some acidifiers to the feed can reduce the occurrence of ascites. Want to try?
--------------------------------------
Reply to 4#cheng_zhang
Okay, thanks for the suggestion. I hope the friends above also see your solution!