Vitamin B7 (Biotin) is an essential micronutrient in animal feed. As a coenzyme for various carboxylases, it is deeply involved in the metabolism of carbohydrates, fats, and proteins, and is crucial for energy utilization, fatty acid synthesis, and nucleic acid synthesis in animals. In practical farming, biotin has significant effects on pigs, poultry, ruminants, and aquatic animals: for breeding sows, it strengthens hoof health, reduces lameness, and improves reproductive performance; for poultry, it promotes skin and feather development and ensures hatchability; for ruminants such as dairy cows, it helps enhance hoof quality and may increase milk yield; in aquaculture feed, its addition promotes growth and weight gain. A deficiency in biotin can lead to growth retardation, dermatitis, hair loss, hoof cracks, and reproductive disorders in animals. Furthermore, the presence of raw egg white, oxidized rancid fats, and certain grains in feed can affect biotin utilization, and intestinal diseases or long-term medication may interfere with its endogenous synthesis. Therefore, rational extra supplementation is needed in feed formulations, with the dosage determined scientifically based on animal species and growth stages.