Negative Effects of Analgesic and Anesthetic Drugs on Sperm Motility: Implications for Assisted Breeding in Managed Rhinoceros
American Association of Zoo Veterinarians Conference 2017
Jack Kottwitz1, DVM; Monica Stoops2, PhD; Jaida Reeves3, BS; Roy Harmon1, BS; Robyn Wilborn3, DVM, MS, DACT; Misty Edmondson3, DVM, MS, DACT; Dawn Boothe1, DVM, PhD, DACVIM, DACVCP
1Department of Anatomy, Physiology, and Pharmacology, Auburn University, Auburn, AL, USA; 2Cincinnati Zoo and Botanical Garden, Center for Conservation and Research of Endangered Wildlife, Cincinnati, OH, USA; 3Department of Clinical Science, College of Veterinary Medicine, Auburn University, Auburn, AL, USA


Drugs utilized for immobilization for assisted breeding may have negative effects on sperm motility. Opioid receptors have been detected on the head, neck, and tail of sperm cells of humans, horses, and boar.1,2,4 The mu and delta opioid receptors modulate sperm motility; however, interspecies variation exists.3 Butorphanol stopped sperm motility in human in vitro studies, while other opioids, such as fentanyl, had partial inhibitory activity.5 Domestic horses and cattle were used to develop an in vitro model evaluating drugs utilized for semen collection in rhinoceros. Semen was collected from stallions with an artificial vagina and from bulls using electro-ejaculation. Semen concentrations were standardized to a minimum 60 million sperm cells/ml. Butorphanol (µ and κ opioid partial agonist/antagonist), naloxone (opioid antagonist), xylazine (alpha-2 agonist) and detomidine (alpha-2 agonist) were added to aliquots of sperm at concentrations from 0.01 µg/ml to 400 µg/ml and incubated for 240 min. Computer-assisted sperm analysis (CASA) was used to determine sperm motility as the percent of progressive motility at drug exposure and specific time intervals thereafter. Butorphanol, detomidine, and xylazine had significant negative effects on sperm motility with increasing drug concentrations. Naloxone had no effects on progressive sperm motility at all drug concentrations evaluated. Opioid drugs (butorphanol and etorphine) were detected in stored seminal plasma from immobilized black (Diceros bicornis), southern white (Ceratotherium simum simum), and greater one-horned (Rhinoceros unicornis) rhinoceros, indicating the potential for negative effects of these drugs on sperm motility. Comparison of drug concentrations from additional serum and seminal plasma samples are pending.


The authors would like to thank the staff of Auburn University North Beef Unit and Horse Reproduction Unit for assistance in semen collection for the in vitro analysis portion of this study.

Literature Cited

1.  Agirregoitia E, Valdivia A, Carracedo A, Casis L, Gil J, Subiran N, Ochoa C, Irazusta J. Expression and localization of delta-, kappa-, and mu-opioid receptors in human spermatozoa and implications for sperm motility. J Clin Endocrinol Metab. 2006;91:4969–4975.

2.  Albrizio M, Lacalandra GM, Micera E, Guaricci AC, Nicassio M, Zarrilli A. Delta opioid receptor on equine sperm cells: subcellular localization and involvement in sperm motility analyzed by computer assisted sperm analyzer (CASA). Reprod Biol Endocrinol. 2010;8:78.

3.  Smith AP, Lee NM. Opioid receptor interactions: local and nonlocal, symmetric and asymmetric, physical and functional. Life Sci. 2003;73:1873–1893.

4.  Vicente-Carrillo A, Álvarez-Rodríguez M, Rodríguez-Martínez H. The mu (μ) and delta (δ) opioid receptors modulate boar sperm motility. Mol Reprod Dev. 2016;83:724–734.

5.  Xu B, Wang ZP, Wang YJ, Lu PH, Wang LJ, Wang XH. The toxic effect of opioid analgesics on human sperm motility in vitro. Drug Chem Toxicol. 2013;36:205–208.


Speaker Information
(click the speaker's name to view other papers and abstracts submitted by this speaker)

Jack Kottwitz, DVM
Department of Anatomy, Physiology, and Pharmacology
Auburn University
Auburn, AL, USA

MAIN : Elephant & Rhinoceros : Analgesic & Anesthetic Drugs Effects on Sperm Motility
Powered By VIN