Theses and Dissertations

Issuing Body

Mississippi State University


Burnett, Derris D.

Committee Member

Lemley, Caleb O.

Committee Member

Dinh, Thu T. N.

Committee Member

Rivera, Daniel

Date of Degree


Document Type

Graduate Thesis - Open Access



Degree Name

Master of Science (M.S.)


College of Agriculture and Life Sciences


Department of Animal and Dairy Sciences


Melatonin is a neuroendocrine hormone most often associated with circadian rhythms, but also has antioxidant and vasodilative properties. Through these properties, exogenous melatonin supplementation has been shown to increase both fetal and postnatal parameters in livestock species, however no research has been performed in swine. This project was split into a prenatal and postnatal study, wherein sows were supplemented from approximately gestational day 38 to 100 before undergoing a terminal hysterectomy for the prenatal portion, and from gestational day 60 to farrowing. Melatonin increased fetal morphometrics in a seasonal dependent manner, where fetuses from melatonin supplemented sows had increased measurements in the Spring replicate. Across the Spring and Fall replicates of the prenatal study, melatonin altered expression of circadian regulatory, metabolic, and myogenic genes within the longissimus dorsi. During the postnatal study, offspring from melatonin supplemented dams had increased body weight and altered circadian regulatory, metabolic, and myogenic gene expression.