Abstract. Leptin is a hormone involved in the regulation of feed intake and energy balance in animals. The expression and secretion of leptin is highly correlated with body fat mass and adipocyte size. The regulation of leptin is integrated into a broad regulatory network including other hormones and cytokines. Leptin's effects on food intake and energy expenditure is thought to be mediated centrally via various neurotransmitters. Peripheral hormones, including insulin and glucocorticoids, stimulate the expression of leptin. While leptin action has been well studied in rodents and humans, its role in farm animals remains to be determined in relation to feed intake and energy metabolism. Leptin may play a role in the regulation of regional fat distribution. The deposition of intramuscular fat (marbling) is positively correlated with the palatability of beef and, therefore, investigations into the mechanisms underlying fat aecretion in this depot are underway. Studying the relationship between leptin and lipid metabolizing enzymes may provide us with clues on the mechanisms governing site-specific fat aecretion in farm animals.