The influence of dietary sunflower oil, rich in n-6 polyunsaturated fatty acids, in combination with vitamin C on ram semen parameters, sperm lipids and fertility.

Abstract

Dietary fats, fed to ruminant animals, have been observed to improve reproductive function. Sunflower oil is one of the richest sources of polyunsaturated fatty acids (PUFAs), over 60% of which is linoleic acid (C18:2). With regard to recommendations for increased consumption of PUFAs, special emphasis has been given to the importance of consuming more antioxidants to prevent lipid peroxide formation. This study evaluated the effects of dietary n-6 PUFAs and vitamin C (VC) in rams-in particular, on semen quality, blood metabolites, sperm lipids and overall fertility. Diets supplemented with SFO and VC increased the proportion of motile sperms and their progressive motility improved (P < 0.01). Rams fed a diet containing SFO had an increased proportion of sperms with normal acrosomes in their semen samples (P < 0.01). The highest levels of lactate dehydrogenase activity (LDH) enzyme were found in control rams (2.60 U mL-1 ). Feeding SFO significantly affected blood triglyceride and cholesterol concentrations (P < 0.05). Diets containing SFO increased the proportion of C18:2c, C20:4, C20:3 and C22 in the sperm lipid composition (P < 0.05). Semen of SFO and VC-fed rams was more fertile than that of control rams when it was artificially inseminated to ewes. Feeding rams with supplemental SFO and VC increased semen quality and improved fertility rates. © 2019 Society of Chemical Industry.