Effects of omega-3 and omega-6 fatty acids on some reproductive parameters in ewes

Abstract

• Fatty acids of the n-6 and n-3 families act as nutraceuticals to complement the sequential processes of follicle and embryo development. However, there is a lack of information on effect of dietary supplementation of n-6 and n-3 fatty acids on different reproductive events in the sheep. Accordingly, in this study, the effect of supplementation of n-6 PUFA rich SoyPreme (SP) or n-3 PUFA rich Flaxtech (FT) on plasma hormone concentrations and some ovarian activity in the sheep were studied. Following the first detected estrus, a total of 44 ewes were allocated into either bazal diet (C, n = 22) or SP (n = 22) treatment until next estrous (pre-mating). At the second estrus, the ewes were mated, and again randomly allocated to either the C or FT allowance until day 15 (post-mating; mating = day 0). Hence, there were four nutrition treatments; CC (n = 11), SPC (n = 11), SPFT (n = 11) and CFT (n = 11). Blood samples were collected to monitor plasma hormon levels. Ewes were slaughtered on day 16th after mating, and the numbers and weights of corpora lutea (CL) and follicles were recorded. Plasma progesterone (P<0.05) and PGFM (P<0.01) concentrations including basal and peak PGFM in the SP ewes during pre-mating period were higher than those of the C ewes. The number of CL were higher in the SPFT ewes compared to the CC and SPC ewes (P<0.05). While the number of small follicules in the SPC, CFT and SPFT ewes were lower than those of CC, that of large follicles in the SPC and CFT ewes were lower than those of CC (P<0.05). It was concluded that short-term (15–17 days) changes in dietary n-6 and n-3 supplementation can have a beneficial effect on plazma hormon consentration and ovarian activity during pre-mating and post-maing, respectively, in ewes.