Effect of ghrelin on feed intake and metabolites in lambs

The objective was to determine the effect of ghrelin on feed intake (FI) and energy metabolites in lambs. Sixteen lambs were randomly assigned to either a treatment (n = 8) or a control group (n = 8). Lambs in the treated group received ghrelin intramuscularly (5 μg/kg of body weight [BW]) and the control group received an equivalent volume of saline 3 h after the morning feeding. Treatments were administered for 4 days. Feed intake was measured daily. Serum samples were collected on days 1, 3, 4, and 5 of the protocol, and levels of ß-hydroxybutyrate (BHB), insulin, and glucose were determined. Lambs treated with ghrelin showed a tendency for lower concentrations of serum insulin on day 5 and showed a tendency for increased FI on day 3. Concentrations of serum BHB and glucose were not different between treated and control lambs. It was concluded that ghrelin did barely affect FI and energy metabolites of lambs treated daily over a period of 4 days.