Second, changes in protein requirements. Egg laying requires more protein during the egg production period. Therefore, the protein content in the feed during the egg production period should be increased according to the increase in the egg production rate. When the chicken egg production rate reaches 50%, the protein content in the feed should reach 15.5%. After every 10% increase in the chicken egg production rate, the digestible protein in the feed should be increased by 0.5%, but not more than 18.5%. The method is mainly to add more fishmeal, bean cake and so on.
Third, changes in mineral demand. As the egg production rate of laying hens increases, the demand for minerals also increases. If there is a lack of calcium in the chicken feed, the chicken will eat soft-shelled eggs, shellless eggs, and even eggs. Therefore, at this time, the calcium content in the chicken feed should be increased from 2% to 3% to 4%, and the phosphorus content should be increased from 0.5% in winter to 0.6%. If the phenomenon of loss of appetite and other phenomena occurs in chickens at this time, the chicken feed salt content should be appropriately increased to 0.1%, and some mineral feed additives should be added appropriately.
Fourth, changes in vitamin needs. As the egg production rate of chickens increases, the demand for vitamins from chickens also increases. Therefore, at this time, we must add it in an appropriate amount. The method is to increase the ratio of various vegetables in the feed except for the feed. The proportion of green vegetables in the chicken feed is increased from 15% in winter to about 32%. When the chicken egg production rate in the spring reaches more than 75%, it should be fed around 15% pellet feed every night at about 8 o'clock to meet the nutritional requirements of laying hens.