INFLUENCE OF MELATONIN TREATMENT ON PUBERTY ONSET IN BUFFALO HEIFERS FROM BULGARIAN MURRAH BREED

Abstract

Current study aimed to investigate the influence of melatonin treatment on puberty onset in buffalo heifers from Bulgarian Murrah breed. The experiment was carried out with еleven clinically healthy pre-pubertal Bulgarian Murrah buffalo heifers alloted in two groups – control (non treated, n=6) and experimental (melatonin-treated, n=5). According to used plan, the treatment was done three time by subcutaneous melatonin implant, containing 18 mg melatonin. Seven days after the last melatonin treatment, progesterone levels were measured by ELISA method and used as an indicator for a presence of cyclic ovarian activity. Data were processed using of a computer statistical program. The average age (12.7±1.1 months and 13.2±0.9 months), body weights (184±22 kg and 232±33 kg) and progesterone levels (0.94±0.37 ng/ml and 1.08±0.16 ng/ml) among the groups did not differ considerably. However, the minimal and the maximal progesterone values in the experimental group (0.96 ng/ml до 1.36 ng/ml) were indicative for a presence of cyclic ovarian activity in 100% of the animals versus 80% in the control group. The concluded analysis shows that melatonin implants application is connected with a trend for earlier induction of cyclic ovarian activity and hastening of a puberty onset in Bulgarian Murrah buffalo heifers.