Effect of starvation and feeding on the plasma cortisol, ghrelin and lipid metabolite concentrations in lambs

Abstract

Ghrelin affects not only growth hormone secretion but also nutrient utilization and metabolic hormone secretion in humans and experimental animals. The mechanisms controlling ghrelin secretion during fasting and postprandial suppression are unknown in ruminant species. In this study, researchers aimed to determine the effects of starvation and feeding on the relationship of plasma ghrelin, cortisol concentrations and plasma lipid metabolites in lambs. The lambs were randomly assigned to the following 4 groups with 4 animals per group according to both the frequency of food administration and ghrelin treatment. In group I, animals were fed ad libitum; in the group II, animals were fed ad libitum and intravenously injected with the ghrelin. twice a week; in the group III, animals were fed once a day and in the group IV, animals were fed twice a day. Blood samples were collected 30 min before feeding and 60 min after feeding to be analyzed for plasma ghrelin and cortisol hormone levels. Ghrelin levels in the highest peak values reached 2, period of fed twice a day lambs and cortisol levels also showed high peak values in animals fed twice a day. As plasma lipid metabolites, fasting NEFA and phospholipids levels showed high values in. the same group. At the present study, suggest that the ghrelin may stimulate cortisol hormone as in vivo ans increase NEFA and phospholipids levels in ruminant species.