Natcha ThongrueangNutchanat ChaibangyangPanida ChanapiwatKampon KaeoketMahidol University. Faculty of Veterinary Science. Department of Clinical Science and Public Health2018-06-112018-06-112018-062017Journal of Applied Animal Science. Vol.10, No.2 (2017), 47-561906-2257https://repository.li.mahidol.ac.th/handle/20.500.14594/15261The aim of this study was to study the effects of adding melatonin at different concentrations on the quality of cryopreserved boar semen. Semen samples (n = 6) were collected by hand-glove technique. Semen samples were diluted with Modena? and divided into 6 groups. According to the concentrations of melatonin at 0 (control, group A), 0.1 (group B), 0.5 (group C), 1.0 (group D), 1.5 (group E) and 2.0 mM (group F) to the lactose-egg yolk extenders used to freeze boar semen with traditional method. Progressive motility, viability and acrosome integrity were evaluated both before and after cryopreservation. The results showed that here was no significant difference in percentage of progressive motility among groups. However, a higher percentage of progressive motility was found in group D (39.17%). A higher percentage of sperm viability and acrosome integrity were found in group F (28.33%) and group F (34.50%), respectively. In conclusion, the present results suggest that adding melatonin between 0.1 and 1 mM during freezing yield a superior post-thawed semen qualities than freezing without melatonin.engMahidol Universityantioxidantboar semencryopreservationmelatoninสารต้านอนุมูลอิสระน้ำเชื้อสุกรน้ำเชื้อสุกรแช่แข็งสารเมลาโทนินJournal of Applied Animal ScienceResearch ArticleFaculty of Veterinary Science Mahidol University