Vitamin C phosphate (L-ascorbic acid-2-phosphate) is formed by attaching a phosphate protective group to the 2-position of standard vitamin C, which, upon entering animals, releases active VC through enzymatic hydrolysis by phosphatase, fundamentally solving at the molecular level the key pain points of ordinary VC, such as its susceptibility to oxidation and loss of potency during feed processing and storage. Feed-grade products typically contain an active concentration of 35% (with 25% and 40% specifications also available), demonstrating exceptional resistance to high temperatures, storage stability, and water stability, making it the most stable vitamin C source in aquatic extruded and pelleted feeds, with bioavailability equivalent to that of equimolar VC. It is widely used for anti-stress, immune enhancement, growth promotion, and liver protection and detoxification in fish, shrimp, and crabs, and is equally suitable for anti-stress in livestock and poultry as well as for incorporation into premixes.