Heat stroke in chickens and ducks and its prevention and control measures

1. Causes of chicken heatstroke: continuous high temperature, low shelf lifting of chicken house, poor heat prevention and cooling facilities, lack of ventilation, causing obstacles to heat accumulation in the house, so that the temperature in the house is high; feeding density is too high, chickens release more heat, which increases the temperature of the house; untimely removal of feces, accumulation of chicken manure increases the concentration of ammonia and humidity in the house, and the heat dissipation of chickens is hindered under the condition of high temperature and high humidity. The energy in the feed is on the high side, which causes the chicken to be too fat and accumulate too much fat.

two。 Chicken heatstroke symptoms and pathological changes: the first symptoms are faster breathing and increased heartbeat. When the ambient temperature exceeds 32 ℃, heat wheezing characterized by intermittent mouth opening and neck extension occurs, the wings are raised and the feathers are dishevelled. The chicken crown and face are bright red and then cyanotic, some are pale, the amount of water to drink increases, and the appetite decreases. When the temperature rises further, the sick chickens stand unsteadily, fall to the ground convulsively, fall into a coma or even fall into a coma, and some suddenly fall to the ground and die. The egg laying rate decreased, the egg shape became smaller, the eggshell became thinner, brittle, the surface was rough, and the egg breaking rate increased. Most of the dead chickens are nutritious, fat or overweight, slow rigor, crop accumulation, gray-white mucus outflow when pressing the nasal cavity, dissection muscle pale, soft, boiled meat-like appearance; blood is purplish black, poor coagulation, liver brittle, swollen, purplish red, myocardial dilatation, pulmonary congestion, hemorrhage and edema, some intestinal catarrhal inflammation; cloacal mucous membrane congestion, bleeding.

3. Preventive measures: reduce the house temperature, reduce the cobreeding density of chickens, strengthen ventilation and improve environmental conditions. Strengthen management, improve feed formula, reduce maintenance consumption of chickens in summer, reduce energy feed rationing, increase crude protein by 1% to 2%, and add appropriate amount of salt and shell powder; change feeding time and mode, avoid high temperature feeding, feed frequently in small amounts in the morning and evening when cool, to stimulate feeding Timely removal of feces, summer feces are sparse, very easy to ferment and decay to produce ammonia and hydrogen sulfide and other harmful gases, induce respiratory diseases, while wet feces are not easy to dissipate heat. Strengthen the work of health and epidemic prevention to prevent the occurrence of various epidemic diseases. Under the condition of heat stress, the level of chicken antibody decreases rapidly and the physique decreases. In addition, summer is also a season with high incidence of Escherichia coli and avian cholera. Regular addition of antimicrobials to feed can prevent and control the occurrence and spread of bacteria. Combined with cooling in the house, chicken coops are disinfected at least twice a week to kill pathogenic microorganisms. To ensure a sufficient and clean supply of cold water throughout the day, at high temperature, the addition of accelerated xiaoshanning, vitamin C and electrolysis can significantly inhibit the increase of chicken body temperature, increase egg production and reduce the ratio of broken eggs and feed to eggs. Some measures against heat stress, such as spraying water, can also be used to wet the chicken body to reduce death.

4. Symptoms of duck heatstroke: duck heatstroke shows restlessness, trembling, elevated body temperature, followed by coma, paralysis, spasm and death, or dyspnea, shortness of breath, wings open and drooping, thirst, unstable walking or inability to stand, and finally died of collapse. Autopsy showed cerebral parenchyma and meningeal congestion, hemorrhage, poor blood coagulation, intestinal edema, lung and ovarian congestion. The egg production of laying duck decreased, and the eggs to be laid were found by autopsy.

Prevention and treatment of heatstroke in ducks: the main preventive measures are heat prevention and cooling, while increasing the nutritional concentration of the diet and increasing the palatability of the feed. The main measures are: duck house, roof, wall whitewashing, a variety of towel gourd, wall climbing tiger and other vines or building Arbor in the playground, etc.; open the doors and windows of the duck house to enhance air circulation, conditional exhaust fans or ceiling fans can be installed; the implementation of spray disinfection with duck can not only effectively cool the temperature, but also kill microorganisms, but also use floor water spraying in the house, roof water spray to reduce the temperature. Release the duck early, close the duck at night, increase the noon rest time and the number of times in the water, in the midsummer sunny day, light the lamp on the playground and let the duck enjoy the cool in the open air for the night. Feed more green fodder and provide plenty of cool drinking water, especially deep well water to avoid storms. Summer humidity is higher, the temperature is high, and there are many mosquitoes and flies, which increase the chance of disease transmission. We should pay attention to the prevention of infectious diseases, especially deworming. The use of drugs for prevention and treatment of duck disease: (1) use disinfectant methylammonium chloride to do a good job of disinfection. (2) correct use of sunstroke prevention drugs. The main anti-heat drugs are: quick-acting summer ning, each bottle dissolved in 1000 grams of water, or 500g of mixture, continuous use for 3 to 5 days, in stress and temperature more than 29 ℃ can be continuous use; heat, each bag dissolved in 300kg of drinking water or 150kg of mixture, while with vitamin C, electrolytic multi-dimensional can effectively prevent the occurrence of heat stroke, is the best choice for summer heat prevention.