What is the key to modern laying hens? How can we achieve high yield? In order to let chickens lay more eggs and produce high-quality eggs, calcium and zinc supplementation should be started two weeks before pregnancy. The calcium content in the diet is 3% ~ 3.5%. This can not only prevent calcium deficiency in chickens, but also avoid the use of calcium sources in the spinal cord, and also ensure the calcium demand of chickens during routine laying. The retention of calcium by old hens is limited, and the retention rate is only about 50%. According to the physiological and biochemical laws of laying hens and experiments, it is proved that the effect of supplementing calcium and zinc to chickens is obvious every day 12:00 ~ 18:00. Eggshells are formed at night, and the calcium contained in them is released into plasma, so that the calcium in bone marrow is not used because of calcium deficiency, so as to maintain the stable and high yield of laying hens.

Calcium-phosphorus ratio Because the absorption level of calcium by chickens is harmed by phosphorus, calcium can be better utilized only if the calcium-phosphorus ratio remains stable. Generally, it is 2 ∶ 1 ~ 1.5 ∶ 1, and the digestibility is high. At the same time, we should pay attention to supplement vitamin D3, which can promote the absorption of calcium by colon, promote the normal thickening of spinal cord, and help improve the quality of eggshells and egg production.

Selection of calcium source When adding calcium to the diet during laying period, the absorbed small molecular calcium hydrate should be selected to replace part of lime powder. Because of the high digestibility of organic calcium in small molecular water, it can meet the needs of laying hens for a large amount of calcium, and also ensure that eggshells produced at night have good compressive strength. Active calcium polyphosphate belongs to small molecular water organic calcium, and its calcium content is above 30. 1%. Its advantage is easy to digest and absorb, and its utilization rate is above 90%. It can disperse a little acid by itself, which is beneficial to reduce the ph value of digestive tract, improve the activity of pepsin and improve the absorption rate of nutrients.

Vitamin C Vitamin C can increase the thematic activity function of thyroid gland, promote the metabolism of calcium in the body, produce calcium from bones, and increase the calcium content in blood, thus improving the composition of eggshells, enhancing the strength of eggshells and laying rate. The amount of food additive of vitamin C in the diet is 50 mg per kg of concentrated feed.

Stress response factors All kinds of stress response factors will harm the absorption and utilization of calcium in chickens, because the stress response will make the laying process and laying time of chickens longer, and the eggs will stay in the eggshell glands for a long time, which will also increase the accumulation of calcium, and then the color of eggshells will become paler and paler. Therefore, the stimulation of stress response factors should be avoided as much as possible in the feeding process, so that the ducks can maintain appropriate relative density and house temperature, which can gradually improve the color and quality of eggshells, ensure the high and stable yield of chickens and improve the economic benefits of feeding.