Cloacoscopy in the Horned Viper (Vipera ammodytes)

This study illustrates the main morphological structures of the cloaca of six adult horned vipers Vipera ammodytes (3.3). The coprodeum is characterized by smooth and thin mucosa, with moderate vasculature. In the centre of the coprodeum the anal sphincter is located, which separates the coprodeum from the colon. Structures of the urodeum are divided by two highly developed septa in female vipers. The urodeum in female vipers is characterized by distinct chambers, which become visible immediately behind the exit of the sphincter of the coprodeum. Vaginal pouches leading to the entrance of the oviduct are visible. The male urodeum is characterized by two distinct structures. In the upper part of the urodeum, the coprodeum sphincter surrounded by a gently folded mucosa, and the urethral papillae surface on a large mucosal protrusion emerging from the dorsal urodeum are visible in male horned vipers. The mucosal protrusion that hosts the urethral papillae can be found in two different appearances, closed or open. The proctodeum is a tubular and muscular structure that leads to the vent. Cloacoscopy is as a safe and effective method for cloaca exploration in both sexes of the horned viper. This technique may be used to assist artificial insemination in the horned viper in the future. Cloaca, endoscopy, urodeum, vaginal pouch, sex determination Detailed knowledge of the snake cloacal anatomy is necessary for clinical evaluation, sex determination, and for artificial insemination programmes in endangered snake species. Literature information regarding the clinical anatomy of the snake cloaca is still scarce (Stahl 2006). The cloaca is not easily thoroughly evaluated during the physical examination of snakes. Rigid endoscopy is a safe and effective method to describe the majority of the most important anatomical structures in various reptiles (Jekl et al. 2007; Divers 2014; Di Girolamo and Selleri 2015; Knotek and Jekl 2015). The objective of this study was to describe the main morphological structures of the cloaca with a special regard to the urodeum and the structures annexed to the reproductive system in the horned viper (Vipera ammodytes) using the rigid endoscope. Materials and Methods Six adult horned vipers (3.3), were included in the study. All snakes originated from a private collection and were healthy. The weight of the animals ranged from 200 to 300 g. All vipers were explored during the putative mating season between April and June 2015 (after a period of hibernation from November 2014 till March 2015). Cloacoscopy could be performed without any sedation or anaesthesia. Snakes were restrained using a plastic tube (Contention tubes, Midwest Tongs, USA), by gently forcing the head and the first third of the animal body inside the tube. Once the snake was safely placed in the tube, the animal was kept in dorsal recumbency. Cloacoscopy was performed with an ureteroscope (1 mm diameter, 45 cm length, 30° angle, Karl Storz endoscope, Tuttlingen, Germany) including an endoscope sheath (2 mm diameter). Pictures were taken with an endo-camera (Veterinary Videocamera III, Karl Storz endoscope, Tuttlingen, Germany) and processed by special software (Debut Video Capture Software Professional v 1.64, NCH software, USA). The ureteroscope was gently introduced into the cloaca through the vent and pushed 2 to 3 cm into the coprodeum. Sterile saline (0.9% NaCl, B\Braun, Germany) was flushed into the cloaca through the endoscope ACTA VET. BRNO 2016, 85: 251-253; doi:10.2754/avb201685030251 Address for correspondence: Dr. Matteo Oliveri Avian and Exotic Animal Clinic Faculty of Veterinary Medicine University of Veterinary and Pharmaceutical Sciences Brno Palackého tř.1946/1, 612 42 Brno, Czech Republic E-mail: [email protected] http://actavet.vfu.cz/ sheath to clean the optic and dilate the cloacal mucosa. The saline was flushed at room temperature. Due to its minimal volume, the fresh saline used did not cause any discomfort to the vipers. The ureteroscope was then slowly withdrawn to allow visualization of the main structures of the cloaca, from the coprodeum to the urodeum and proctodeum. Once the urodeum was reached in the female viper, the optic was aligned with the entrance of the oviduct and a 4 Fr. cannula (Transcervical Insemination Catheter, Minitube, Germany) was gently inserted into the oviduct, overcoming the vaginal sphincter. Sex determination was confirmed by probing of the hemipenal pockets of the snakes following cloacoscopy.