Use of ketamine associated with detomidine or xylazine for semen collection with electroejaculation in pampas deer (Ozotoceros bezoarticus)

Semen collection by electroejaculation under general anesthesia is a frequent method used in wild animal species. The study aimed to compare the effectiveness of two anesthetic protocols (ketamine/detomidine (KD) or ketamine/xylazine (KX) for semen collection with electroejaculation in pampas deer (Ozotoceros bezoarticus) males. Also, compared the physiological and hematological changes with the two anesthetic protocols. Seven pampas deer males were anesthetized with both protocol in an overcorssed design, reverting the anesthesia with atipamezole in both protocols. The induction time, recovery time, and the time of the anesthesia procedures did not differ between both anesthetic protocols. The heart rate was greater when animals were anesthetized with KD than when KX was used (55.33 ± 2.7 bpm vs 45.12 ± 2.6 bpm; P = 0.05). Although there was no difference according to the anesthetic protocol, the oximetry values were below those considered normal in other species. When animals were treated with the KD, the red blood cell number, hematocrit, and hemoglobin concentration were greater than with the KX protocol (17.1 ± 1.3 ×10⁶/µL vs 15.9 ± 1.3 ×10⁶/µL; P = 0.006; 47.2 ± 3.4% vs 43.9 ± 3.4%; P = 0.008; and 14.8 ± 0.8 g/dL vs 13.8 ± 0.8 g/dL P = 0.01, respectively). Less number of electrical pulses were required for ejaculation in animals treated with KX than with KD (39.8 ± 2.6 vs 52.4 ± 2.6, P = 0.04). In samples collected from animals treated with KD, the total number of sperm with integral acrosome was lower, but the percentage of sperm with normal morphology was greater than in animals treated with KX (67.8 ± 67.0 × 10⁶ sperm vs 243.1 ± 71.6 × 10⁶, P = 0.03 and 40.0 ± 2.3% vs 30.6 ± 2.7%, P = 0.02; respectively). In conclusion, the use of KX induced less physiological changes, appearing also advantageous in semen quality.