Vol. 9, Special Issue 6, Part A (2025)

Vasectomy in captive male Nilgai (Boselaphus tragocamelus) at Gadag Zoo, Gadag, was conducted in seven adult and six subadults under Xylazine-Ketamine anaesthesia. Mean ± SD of induction dose of Xylazine-Ketamine in adults was 214.29±55.63 mg-478.57±114.95 mg and in subadults was 150.00±0.00 mg-358.33±20.41 mg. Anaesthesia was maintained with bolus doses of Ketamine administered intravenously. Mean ± SD of induction time, duration of anaesthesia, recovery time and total duration of whole procedure was 17.77±9.88 min, 31.62±6.34 min, 10.33±9.15 min and 55.23±9.77 min respectively. Surgical approach to spermatic cords was separate skin incisions on cranial scrotal neck region. Vas deference was exteriorised from spermatic cord and occluded with two vascular surgical clips placed at a distance of five centimetres apart. The portion of vas deference between the clips was excised and skin incision closed. Xylazine-Ketamine anaesthetic combination provided good depth of anaesthesia for safe restraint during surgical procedure. Other necessary medications were administered and the anaesthetic effect was reversed using yohimbine intravenously. All the animals recovered from anaesthesia uneventfully and surgical wound healed without any complication. Post-operative observation for a period of one year showed retention of bluish-grey coat colour in adults and changing of coat colour from brownish-grey to bluish-grey in subadults as they grew older. Vasectomy surgery can be safely performed in captive nilgai as birth control measure without affecting male-specific traits.