The use of dl-methionine 99 feed grade can be supplemented according to the nutritional requirements of livestock and poultry. Methionine is commonly used in poultry feed. Feeding methionine to ruminants will be ineffective due to the deamination of methionine by rumen microorganisms, but methionine hydroxy analogs only provide the corresponding carbon skeleton of methionine without deamination. At the same time, since there is enough ammonia in the rumen as a source for the addition of amino groups, it is converted into methionine.

In pigs, the amount of dl-methionine 99 feed grade used is generally 50% of lysine, and sufficient methionine must be added to the feed of broiler laying hens. If rapeseed cake and cottonseed cake are used to replace soybean meal, the addition of lysine must be increased by 20%. If soybean meal is replaced by fish meal, the addition of lysine can be reduced by 20%. When formulating, it should be flexibly mastered according to different species of animals, different stages and different types of feed raw materials, etc., in order to obtain more feeding benefits.