The wild elasmobranch population has decreased significantly because of accidental and intentional catch in the fishery industry and the disappearance and devastation of habitats due to marine development (Fowler et al., 2002). More than 80 species of elasmobranch, such as family Sphyrnidae, Lamnidae, and Myliobatidae, are listed in Appendices I-III of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (2021) because of their degree of extinction and are subject to the international trade regulations. Hence, animal

ABSTRACT. In Kaiyukan, the research activity is accelerated to contribute to the conservation of biodiversity coupled with the sustainable management of our aquarium. For contribution of the conservation, the veterinarians in our aquarium are striving for the research relevant to the accumulation of the clinical knowledge and the development of the clinical technique in aquatic organisms as a black box in biology.

The purpose of this study was to determine the optimal imaging protocol for contrast‐enhanced computed tomography (CECT) using micro‐CT (μ‐CT) for the posterior cardinal vein (PCV), dorsal aorta (DA), hepatic portal vein (HPV), kidney, liver, cephalic arteries (CAs), and gills of Cloudy Catsharks Scyliorhinus torazame. Additionally, we examined the availability of CECT screening for the coelomic organs. Different doses of iopamidol (100, 300, 500, and 700 mg iodine [mgI]/kg) were administered intravenously for 20 s in six sharks. The CT scans from the pectoral girdle to the pelvic girdle were performed at 0–600 s after administration. Contrast‐enhanced CT imaging of the CAs, gills, and coelomic organs was examined. Assessment of the signal enhancement value revealed that the PCV was easily visualized with all contrast doses at 25 s. The CAs, gills, and DA were visible at a slightly higher dose (CAs and gills: 200 mgI/kg at 40 s; DA: 300 mgI/kg at 50 s). The HPV was obvious at a dose of at least 500 mgI/kg after a 150‐s delay. The parenchyma of the kidney had a contrast effect at 300 mgI/kg, 150 s after the contrast effect of the renal portal system disappeared. The liver, which stores a lot of lipids, had poor overall contrast enhancement that was optimized at the highest dose of 700 mgI/kg. Contrast‐enhanced CT screening at 700 mgI/kg and 150 s is likely to obtain the optimal imaging of the reproductive organs, such as the ovary, oviducal gland, uterus, and testis. The present findings can be applied not only to clinical practice but also to academic research and education on elasmobranchs in aquariums.

Surgery Case reportFemale Asian small-clawed otters (Aonyx cinerea ) in aquariums and zoos might need to be sterilized to prevent reproduction and disease or for pedigree-based genetic management. When performing contraceptive surgery, ovariohysterectomy or ovariectomy via laparotomy is required.However, there is concern that self-injury, such as scratching at the surgical incisions, can lead to numerous complications. Meanwhile, in the field of companion animal medicine, laparoscopic surgery has become extremely popular and has been used for adrenalectomy, cholecystectomy, hepatic lobectomy, and splenectomy [1]. Additionally, laparoscopic ovariectomy and ovariohysterectomy have usually been performed on dogs and cats [2-4]. According to reports, these procedures result in smaller surgical incisions and less postoperative pain [2, 5-7]. Moreover, the incidence of complications is low and length of hospitalization is short [8]. These advantages of laparoscopic surgery are thought to be of great benefit in the ovariohysterectomy of otters. This report describes the surgical procedures, surgical outcomes, and postoperative management of laparoscopic ovariectomy performed on two otters at Osaka aquarium KAIYUKAN. Laparoscopic ovariohysterectomy was performed at the Kanai Veterinary Surgery hospital on two female Asian smallclawed otters from Osaka Aquarium KAIYUKAN. Each otter underwent surgery on a different day. Otter A was a 3.09kg, 10-year-old, and otter B was a 3.88-kg, 9-year-old. Both otters had never given birth due to pedigree-based genetic management. During a biannual health examination under anesthesia, renal calculus was confirmed by radiography and ultrasonography in both otters. Otter B had previously undergone cystolithotomy. However, hematolog ical examination before surgery revealed no abnormalities.Both otters were fasted for 12 h, and water was withheld for 6 h before surgery. On arrival at the hospital, the otters were placed into an induction chamber and sedated with sevoflurane (Sevofrane, Maruishi Pharmaceutical Co., Ltd., Osaka, Japan). They were then weighed and intubated using a 3-mm endotracheal tube. Sedation was maintained with 2.5-3.5% sevoflurane with 100% oxygen (1 L/min) using an anesthesia machine (Apollo, Dräger, Lübeck, Germany), which

The tufted puffin, Fratercula cirrhata , is a mediumsized seabird belonging to the family Alcidae and is widely distributed throughout the North Pacific Ocean. It breeds mainly on islands and cliffs in the Sea of Okhotsk, the Bering Sea, the Kuril Islands, Alaska, and the coast of California, and, in Japan, a small number of birds breed on islands in eastern Hokkaido. F. cirrhata is classified as 1A in the endangered species list, i.e., critically endangered, in the Japanese Red Data