In livestock production, protein feeds are both scarce and expensive. In order to save protein feed, make rational use of protein and increase the utilization of protein in the diet, the majority of farmers should pay attention to the following points. First, feed should be diversified in conjunction with diet: The type and amount of essential amino acids contained in proteins vary depending on the type of feed. A variety of feeds can complement each other, can play a complementary role of amino acids, can improve the balance of amino acids in the diet, improve protein utilization and feeding effect. In the practice of breeding, according to the needs of livestock and poultry, a proper selection of appropriate feeds should be carried out with a reasonable aim, so as to diversify the feed as much as possible. It is also necessary to prevent the blind pursuit of the number of feed types, because some of the nutrients after mixing are not balanced and the feeding effect is even worse. Second, supplemental amino acid additives: In livestock and poultry diets that lack one or more essential amino acids, the missing amino acids are added directly to supplement the deficiency in the feed and amino acid balance is sought. According to reports, adding 1 kg of methionine to pig and chicken diets is equivalent to feeding 50 kg of fish meal. Adding 0.15% methionine to the diet before pig fattening can save 100 tons of formulated feed per ton of methionine, which has significant economic effects. Therefore, the application of amino acid additives is not only an important means for modern animal husbandry to improve the protein nutrition of livestock and poultry, but also a new way to increase the efficiency of feed utilization and solve the shortage of protein feed. Third, a reasonable supply of protein nutrition: High or low protein levels in diets are harmful to livestock and poultry. Excessive amounts of protein eaten by livestock and poultry do not increase nitrogen deposition in the body. Because pigs and poultry can't keep the protein they eat on the day until tomorrow, they will increase the excretion of nitrogen in the urine, leading to a decrease in protein utilization. Therefore, it is necessary to balance the supply of amino acid-balanced protein nutrition according to the livestock and poultry raising standards. Two different protein feeds, such as bean cake and fish meal, have better mixed feeding and amino acid complementation. 4. Proper proportions of protein and energy in the diet: When nutrients such as carbohydrates and fats that supply energy in the diet are deficient, they will inevitably increase the decomposition of proteins to meet the energy needs of livestock and poultry, and reduce the use of synthetic protein and animal products, resulting in protein utilization. The rate is reduced. Not only that, but protein also loses some of its energy in the process of converting energy. Therefore, in the practice of breeding, sufficient energy should be supplied to avoid using protein as energy. Fifth, the processing of bean feed processing: The trypsin inhibitor contained in feed such as beans and raw bean cake can affect the digestion and absorption of proteins. However, after wet heat treatment, inhibin can be destroyed and protein utilization can be improved. PIV3 Nucleic Acid Test Kit PIV3 Nucleic Acid Test Kit Guangdong Hecin Scientific, Inc. , https://www.hecinscientific.com