This product is a white to off-white crystalline powder (CAS 59-51-8) manufactured via a patented process using petrochemical raw materials. Supplied in original 25 kg/bag packaging, it has a shelf life of 5 years when stored in a cool, dry place. It is the most widely used single-amino-acid additive in poultry and aquaculture feed. As the "first limiting amino acid" for poultry and aquatic animals, it directly addresses the natural methionine deficiency in corn–soybean meal diets. Adding 0.5–2 kg per ton of compound feed promotes protein synthesis, maximizes growth rate and muscle deposition, improves feather quality in broilers, egg weight and selenium content in laying hens, and reduces drip loss and feed conversion ratio; in aquaculture, it improves feed conversion and disease resistance; in pigs and ruminants, it increases piglet survival rate, raises milk selenium content, and reduces reproductive problems such as retained placenta. An industry classic benchmark —adding 1 kg of methionine to feed is roughly equivalent in nutritional value to 50 kg of fish meal,and can significantly replace high-priced protein ingredients, lower formula costs, and is a standard product for farms and feed mills to control costs and improve efficiency.