Feline overpopulation raises issues concerning health, ecology, economy, and ethics. Procedures to limit overpopulation should carefully address animal welfare, efficiency, costs, and feasibility. Vasectomy in unowned cats is suggested as preferable to standard neutering as it maintains male sexual behaviour which may induce ovulation and pseudopregnancy in intact females and may prevent immigration of other males. Vasectomy is not performed routinely because it is fastidious, time consuming and requires more material than standard neutering. We describe epididymectomy as an alternative. In a first experiment, we analysed semen, testosterone, behaviour and pain in six experimental cats before and after epididymectomy, and after castration two months later. Excised tissues were analysed histologically. Testosterone concentrations did not differ significantly between intact and epididymectomised animals but were significantly different after castration. Sexual behaviour and testicular spermatogenesis persisted after epididymectomy, but with a marked drop in the semen count after 7 days. The Glasgow pain scores did not differ significantly after epididymectomy and castration. In a subsequent experiment, 20 privately owned cats were epididymectomised and castrated immediately afterwards, to analyse the learning curve and perioperative complications. The time required for an epididymectomy was significantly shorter than for castration. The study confirms that epididymectomy is quicker and less invasive than castration, it is associated with minimal risks and post-operative pain while easy to learn and inexpensive. Further field studies are required to test its efficiency for feline feral population control or in other species such as in bears, lions or deer, where infertility is required, and castration not wanted.
Etienne Furthner 1, Rosalie Fabian 2, Anja Kipar 2, Gerhard Schuler 3, Fredi Janett 4, Nicolas Nudelmann 5, Annette P N Kutter 6, Iris M Reichler 7
Theriogenology. 2023 Apr 1; 200:168-178. doi: 10.1016/j.theriogenology.2023.02.009.
1Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland; Centre d’Etude en Reproduction des Carnivores, Ecole Nationale Vétérinaire d’Alfort, Maisons-Alfort, France. Electronic address: efurthner@gmail.com.
2Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
3Clinic for Obstetrics, Gynaecology and Andrology of Large and Small Animals, Faculty of Veterinary Medicine, Justus-Liebig-University Giessen, Giessen, Germany.
4Section of Andrology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
5Centre d’Etude en Reproduction des Carnivores, Ecole Nationale Vétérinaire d’Alfort, Maisons-Alfort, France.
6Section of Anaesthesiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.7Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.