Stimulatory effects of fish oil and vitamin E on ovarian function of laying hen

Abstract

In recent years, there has been an increase in the consumption of omega-6 fatty acids (FAs) over omega-3. Moreover, the antioxidant nature of oil supplemented diet in human and animal studies is not clear. In this work, the n-3 effects on hen ovarian cells, ovarian dynamics, serum FA profiles and expression level of apoptosis genes in the presence or absence of vitamin E were studied. Sixty-eight laying hens were randomly divided into four groups and the groups were fed the following diets: basal diet +1.5% sunflower oil (control; C); basal diet +1.5% sunflower oil +1.1 U alpha-tocopherol/hen/day (E); basal diet +1.5% fish oil +1.1 U alpha-tocopherol/hen/day (n-3 + E); and basal diet +1.5% fish oil (n-3). In E, n-3 + E and n-3, small yellow follicle numbers were higher than control (p < .05). Large yellow follicle numbers as well as total numbers of follicles of n-3 + E and n-3 were higher (p < .05) than control and E. The rate of ovulation was significantly (p < .05) higher in n-3 (96%) compared to the control (89%). The proportion of intact primordial follicles in n-3 and n-3 + E was significantly more than control and E (p < .01). The expression of Bak (Bcl2 antagonist/killer) was significantly (p < .05) higher in control than the other groups. There was significant reduction in expression of Cas9 in n-3 and E compared to the control and n-3 + E (p < .05). While omega-3 and vitamin E can protect ovarian cells from apoptotic death, omega-3 source could have promoting roles on follicular development and ovulation rate, being independent of dietary vitamin E.Highlights Despite the perceived importance of supplementing antioxidant with fatty acids, our results indicated that alone low level of n-3 has a great influence on ovary performance.

Keywords

• apoptosis
• follicogenesis
• n-3pufa
• ovary
• vitamin e