The Effect of Galanin on the Mean Plasma of Gonadotropins in Female Goats fed Different Levels of their Energy Requirements

Introduction: The existence of a close relationship between energy status and reproductive function is well documented, but its underlying mechanisms remain to be fully unfolded.Galanin is an orexigenic agent and has been demonstrated as putative regulator of gonadotropin secretion in rats. There is no study to show the interaction of different levels of energy intake and galanin on gonadotropins secretion in ruminants, therefore the goal of this study was to determine whether galanin affects the mean plasma concentrations of LH and FSH in the female saanen goats fed different energy content in diets. Methods: Nine female saanen goats were randomly divided into 3 groups.Animals of all groups were fed either 50% , 100% and 150% energy content in diet for a month.After a month, goats were received 1μg galanin /kg body weight into their jugular vein.Blood samples were collected every 30 minutes from jugular vein of all goats 3.5h before and 3.5h after injection of galanin.Blood plasma were assayed for plasma LH and FSH concentrations by RIA. Results: Injection of galanin only in 150% dietary energy intake significantly decreased the mean plasma concentrations of LH and FSH whereas in 50% and 100% dietary energy intake , injection of galanin had no effect on the mean plasma concentrations of LH and FSH. Conclusion: These results indicated that galanin may negatively affects mean plasma concentrations of LH and FSH in the female saanen goats only with positive energy balance.