Environment and feed for laying hens in autumn

Environmental regulation and control

The growth and development of laying hens are affected by temperature, humidity, light, harmful gases, shock, noise, environmental hygiene, disinfection, mosquitoes and flies and other factors. The optimum temperature for laying hens is 18 ℃ ~ 25 ℃, and the laying rate is the best at 20 ℃. During high-temperature heat stress, the adverse reactions were crown pallor, anemia, decreased resistance, etc., the egg laying rate decreased by 10% to 20%, and the average egg weight decreased by 5% to 10%. The decline in eggshell quality is reflected in the increase of thin shell eggs, broken eggs, soft shell eggs, non-shell eggs, increased mortality, and irreversible damage to fallopian tubes and ovaries. Therefore, improving the ability of heat stress and preventing heat stress are the guarantee to ensure the economic benefits of laying hens in autumn. The temperature difference between day and night in autumn increases, and the invasion of cold air gradually increases, which will cause temperature fluctuations. At this time, according to the weather changes, pay attention to keep warm at night to avoid cold and respiratory diseases caused by cold. Poor ventilation in the chicken house can lead to lack of oxygen. Due to the high temperature and large amount of drinking water, chicken manure becomes very thin, which is easy to ferment to produce a large amount of ammonia, hydrogen sulfide and other harmful gases, resulting in stress, which not only reduces the laying performance of laying hens, but also easily causes respiratory diseases. Among them, ammonia destroys the cilia and inner wall of the trachea, and viruses and E. coli enter the respiratory system, leading to respiratory diseases.

Feed preparation

The low laying rate of hens is directly related to the feed, especially the contents of vitamin A, vitamin D, pantothenic acid, nicotinic acid, folic acid, choline biotin and so on. When the temperature is high, the feed intake of laying hens is generally small, in the general feed formula, energy can meet their needs, other ingredients such as vitamins will be insufficient, especially fat-soluble vitamins. Due to the influence of heat stress, the demand for vitamins in laying hens increased, while the vitamin in feed was affected by high temperature, the damage was intensified and the content decreased. In particular, the vitamin content of corn is generally lower than that of fresh corn, and inferior corn (such as mildew) is mostly on the market in autumn, which aggravates the harm of poor raw material quality. The above factors caused the deficiency of fat-soluble vitamins needed by laying hens, which seriously affected the laying performance of laying hens.

Chickens are inherently sensitive to mycotoxins, and low levels of mycotoxins in feed will cause mass death of chickens. Mycotoxin damages the immune system of the body and reduces the immune response. the effects on laying hens are mainly as follows: decreased immunity, poor immune effect of vaccine, shrinking ovaries and fallopian tubes, decreased egg production and abnormal egg production; reduced feed intake, decreased production performance, reduced feed reward, and decreased hatching rate of breeding eggs. The harm caused by different mycotoxins to laying hens is different. among the known mycotoxins, ergot toxin, single-ended sporotoxin, humus toxin, zearalenone, aflatoxin, ochratoxin and so on.

Due to the influence of heat stress, the feed intake of chickens is low. in order to ensure egg production according to the feed intake of chickens, the energy level and nutrient concentration in the diet should be appropriately increased and the dietary volume should be reduced to compensate for the decrease of nutrient intake caused by heat stress.