Effect of kisspeptin-10, LH and hCG on serum testosterone concentrations in stallions, donkeys and mules

Abstract This study was conducted to determine the response of serum testosterone (T) in male equines (stallions, donkeys and mules) after administering intravenous doses of kisspeptin-10 (KP-10), human chorionic gonadotropin (hCG) and luteinizing hormone (LH) and saline as a control. The animals were divided into four groups of three each: Group I, 3 ml of 0.95% saline; Group II, 50 μg KP-10; Group III, 2500 IU hCG and group IV, 400 μg LH. The administration of KP-10 and hCG to stallions resulted in a significant increase in serum T concentration at 240 min; whereas it was significantly higher at 30, 60, 120, and 240 min with LH treatment as compared to pre-dose concentrations. Both KP-10 and hCG significantly elevated the T concentrations in donkeys at 120 and 240 min, respectively; whereas it was significantly higher at 60, 120, and 240 min with LH treatment as compared to pre-dose concentration. Both KP-10 and LH elevated T in donkeys at 240 min as compared to the control and hCG concentrations. After 120 and 240 min, T concentrations in mules were higher (p