This study was conducted to determine melatonin and alpha (α) casein levels in sheep milk. The study material was 40 milk samples taken after milking from, healthy, 3-year-oldlactating sheep from 4 different farms (10 sheep from each farms). In the milk samples taken, melatonin levels were determined by Enzyme-Linked ImmunoSorbent Assay (ELISA) and the density of α-casein levels by electrophoresis (SDS-PAGE).

It was determined that the lowest value of milk melatonin levels in the enterprises was 80.0 ng/L and the highest value was 92.4 ng/L. In addition, these values were determined as 82.7 ng/L and 84.3 ng/L in the other two enterprises. There was no significant difference between farms in terms of melatonin levels (p>0.05). When α-casein levels were examined, a significant difference was found between farms (p<0.001). α-casein level density was also lowest in the enterprise with the lowest melatonin level. It has also been determined that casein density is also high in farms where melatonin levels are high. As a result of the study, melatonin and α-casein levels were determined, also a parallelism was observed between the two parameters. Therefore, it has been concluded that farms can benefit from these parameters in the growth, development and disease resistance of the offspring.