ò-Melanocyte-stimulating hormone (ò-MSH) is an endogenous peptide hormone and neuropeptide. It is a melanocortin, specifically, one of the three types of melanocyte-stimulating hormone (MSH), and is produced from proopiomelanocortin (POMC). It is an agonist of the MC<sub>1</sub>, MC<sub>3</sub>, MC<sub>4</sub>, and MC<sub>5</sub> receptors. It contains 23 amino acid residues.
ò-MSH is also known to decrease food intake in animals such as rats, chicken due to the effect of proopiomelanocortin (POMC). Research was performed to see the effect ò-MSH has on chicks, and it has been found that chicks responded with a decrease in food and water intake when treated with ò-MSH. The experiment showed that ò-MSH causes anorexigenic effects in chicks.