• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.4
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• pp.247-258
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• 2021

To understand restoration and conservation projects conducted in Korea for endangered freshwater fishes and amphibians/reptiles, information about Request for Protocols-related studies on restoration, breeding, and release were collected. Trends of studies were visualized via word clouds and VOSviewer program using a text mining technique. Analysis of restoration projects for endangered freshwater fishes elucidated that most research studies conducted to date were focused on genetics and release through captive breeding that could be classified into captive breeding and habitat environments. As for research projects related to amphibians/reptiles, monitoring projects had the highest number, followed by genetic, translocation, and monitoring studies. In addition, restoration projects for amphibians/reptiles included a large number of post-capture translocation projects. Thus, many projects were confirmed by public institutions rather than by the Ministry of Environment. Network analysis revealed that it was largely classified into capture, translocation, and Kaloula borealis. Based on these results, limitations, achievements, and challenges associated with projects conducted thus far are highlighted. Research directions for future restoration and conservation of endangered freshwater fishes and amphibians/reptiles in South Korea are also suggested.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.6
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• pp.331-344
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• 2020

Ship's hydrodynamic coefficients in manoeuvring equations are generally derived by captive model tests or numerical calculations. Empirical formulas have been also proposed in some previous researches, which were useful for practical predictions of hydrodynamic coefficients of a ship by using main dimensions only. In this study, ship's hydrodynamic coefficients based on empirical formulas were optimized by using its free running test data. Eight manoeuvring performance indices including steady turning radius, reach in zig-zag as well as well-known IMO criteria indices are selected in order to compare simulation results with free runs effectively. Sensitivities of hydrodynamic coefficients on manoeuvring performance indices are analyzed. And hydrodynamic coefficients are tuned within fixed bounds in order of sensitivity so that they are tuned as little as possible. Linear and nonlinear coefficients are successively tuned by using zig-zag and turning performance indices. Trajectories and velocity components by simulations with tuned hydrodynamic coefficients are in good agreements with free running tests. Tuned coefficients are also compared with coefficients by captive model tests or RANS calculations in other previous researches, and the magnitudes and signs of tunes are discussed.

• Journal of Veterinary Clinics
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• v.39 no.2
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• pp.70-74
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• 2022

A 14-year-old intact male captive leopard (Panthera pardus) first presented with a focal alopecic lesion on the dorsal aspect of the distal one-third of its tail. Although itraconazole was administered, the lesion progressed deeper and became ulcerated due to self-trauma. Due to the wild nature of the leopard, daily dressing of the wound and replacing the bandages without anesthesia became too dangerous, and amputation became necessary. A postoperative tissue sample was submitted for histopathological examination, and tramadol, amoxicillin/clavulanate, and gabapentin were administered. In the days following the amputation, the leopard's appetite significantly decreased, and the patient passed away 18 days later. Histopathological examination of the specimen revealed well-differentiated squamous cell carcinoma (SCC). In hindsight, had more cells been collected by a fine-needle aspirate (FNA) biopsy or had additional FNA biopsies been performed, SCC might have been diagnosed based on its cytological features rather than delayed histopathological findings. The current study highlights the critical reasons why clinicians may often misdiagnose SCC and the importance of being more aware of potential tumors in ulcerative lesions, which are often incorrectly treated as infectious skin diseases. This is also the first report of cutaneous SCC in a leopard.

• Journal of Navigation and Port Research
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• v.43 no.6
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• pp.369-376
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• 2019

Ship hydrodynamics in the confined waterways is challenging. When a ship is maneuvering in confined waterways, the hydrodynamic behavior may vary significantly because of the hydrodynamic interaction between the bottom of the ship hull and the seabed, or so-called shallow water effects. Thus, an accurate prediction of shallow water and bank effects is essential to minimizing the risk of the collision and the grounding of the ships. The hydrodynamic derivatives measured by the virtual captive model test provide a path to predicting the change in ship maneuverability. This paper presents a numerical simulation of captive model tests to predict the maneuverability of a ship in confined waterways. Also, straight and zig-zag simulation were conducted to predict the trajectory of a ship maneuvering in confined waterways. The results showed that the asymmetric flow around a ship induced by vicinity of banks causes pressure differences between the port and starboard sides and the trajectory of a ship maneuvering in confined waterways.

• Journal of Veterinary Clinics
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• v.27 no.1
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• pp.93-96
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• 2010

We describe a case of enterolithiasis in an eight-year-old male Grant's zebra (Equus burchelli boehmi) that died after a 10-day history of depression, anorexia, dehydration and colic. On necropsy, an enterolith was discovered at the conjunction of the descending colon and the rectum. The spherical enterolith weighed 1,660 g and was $13.5cm{\times}8cm$ in size. According to scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), the nidus consisted primarily of $SiO_2$ with outer layers of magnesium and phosphate. The formation of enteroliths is closely related to diet. We suggest that this captive zebra's diet, which consisted primarily of alfalfa hay with mineral supplements, was the cause of enterolithiasis in this case. This is the first report of enterolithiasis in a captive equid in Korea. Our findings provide information valuable for the development of dietary guidelines to prevent enterolithiasis in captive wild equids.

• Journal of Veterinary Clinics
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• v.26 no.3
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• pp.246-258
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• 2009

This study was conducted for behavioral characteristic analysis of the Asiatic Black Bear in a limited space. Behaviors of eight Asiatic Black Bears were classified into 13 normal stances and locomotor activities, 15 normal maintenance behaviors, 9 locomotory compulsive behaviors, 2 non-locomotory compulsive behaviors through the 3 years of monitoring. The bears had originally been released into the Jiri National Park for Asiatic Black Bear Restoration Project and were withdrawn again because of several reasons such as habituation to humans, and apiary damage. Through the monitoring of 6 hours per day during 3 months, classified behaviors were analyzed based on sex, age, observing month, observing timing, captivity period, and captive form. The total rate of stereotypic behaviors was $26.51{\pm}13.38%$. Among these, RA(Rest_A) was rated high as $47.32{\pm}18.32%$. In addition, SP(Standard pace), HR(Head rear), EP(Extended pace) were most frequently observed behaviors. The time budget of TFS(Two feet stand), SA(Sniff_A) and SB(Sniff_B) on females and younger individuals were relatively higher than male and older individuals. So we confirmed that females and younger individuals had more wariness and curiosity. As the period of captivity took longer, the rate of stereotypic behaviors was higher and more stereotypic behaviors were observed in the afternoon. At night, behaviors related with resting like Rest-A, Rest-B, Lying down, Lying on abdomen, Sitting were more frequently observed. We concluded that the captive state could affect the behaviors of Asiatic Black Bear and long term research should be necessary.

• Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.213-224
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• 2024

Betta rubra, classified as endangered fish species by the International Union for Conservation of Nature (IUCN), has been successfully bred and raised in captivity for two generations under laboratory conditions. This study aimed to provide comprehensive information on the captive breeding of B. rubra, focusing on various parameters crucial for ex-situ conservation and domestication. The research involved breeding trials, embryo and larvae observation, first feeding experiments, larva and fry rearing trials, and the evaluation of growth and reproduction in two generations. The study revealed that the female B. rubra, with an average total length of 5.17 ± 0.15 cm and weight of 1.61 ± 0.06 g, produced an average of 73.67 ± 7.09 eggs, 34.33 ± 5.13 total larvae, and exhibited a hatching rate of 46.67 ± 5.77%. The embryogenesis process commenced on the day of spawning (dps) and continued until the eggs hatched at 6 dps. Larvae development and yolk absorption occurred from 0 to 6 days post-hatching (dph). The study also examined the impact of different initial feeding options, with chopped Tubifex resulting in the most significant in- crease (p < 0.05) in length. The growth pattern of B. rubra larvae showed slow initial growth during the first seven days, followed by a rapid exponential growth phase from day 8 to day 39. Two generations of B. rubra (G1 and G2) were successfully bred in captivity, with G2 showing a better tendency for growth in length and weight compared to G1. Notably, there were no significant differences (p > 0.05) in reproductive success between the wild-origin broodstock (G0), G1, or G2. This research contributes valuable insights into the captive breeding of B. rubra and its early life stages, offering critical information for the conservation and sustainable management of this endangered species. Further research is needed to explore the long-term effects of domestication on behavior, physiology, and phenotypic diversity.

• Journal of Veterinary Clinics
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• v.22 no.4
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• pp.401-403
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• 2005

A seven-year old female captive Japanese macaque (Macaca fuscata) was mobbed by its cage mates and subsequently died due to trauma. An incidental finding of multiple biliary cystadenoma in the liver is herein reported. Grossly, multiple small cysts were observed throughout the surface of the liver. One particular cyst that measured $1.3\times1.2\times1.0cm$ and contained mucinous fluid was observed in the center of the liver. Microscopically the cysts were lined by biliary epithelium that varied from simple cuboidal to columnar cells. Signs of malignancy and metastasis to other organs were not observed. This is the first report of biliary cystadenoma in Japanese macaque.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.799-805
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• 2017

The whistle sounds of three Beluga whales Delphinapterus leucas were recorded four times, for an hour each time, in 2016 and analyzed to obtain the most stable and basic acoustic characteristics of the whales in captivity. This study investigated the whistle characteristics of beluga whales and the relationship between whistle sounds and behavior to understand the meaning of the whistle sounds. The whistles were classified into six types (flat, ascending, descending, hump, dip, and wavy type) by their frequency contour and shape. The most common type was the ascending type, accounting for>30% of total whistles. The fundamental frequency of whistles was 2.0-8.6 kHz. Four types of behavior were related with the sounds of beluga whales (aggressive, submissive, affiliative, sexual behavior). A flat whistle was the most recorded in the group and an aggressive act was observed in association with the flat whistle. A dip whistle were recorded more when submissive acts were observed.

• Korean Journal of Veterinary Service
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• v.35 no.1
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• pp.47-52
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• 2012

Crocodile farms are getting popular in Bangladesh in an economic point of view. In one of the farms, some crocodiles were found sick and three of them died between May and July in 2006. This investigation was performed to diagnose the cause of the death. Routine postmortem examination was conducted. Samples were collected in 10% neutral buffered formalin for histopathology and in falcon tube for microbiological study. Additional swabs were collected in nutrient broth. Histopathological and microbiological studies were conducted using routine procedures. In addition Giemsa, Gram and PAS stains were performed to detect the organism in tissues. Grossly, esophagus, trachea, lungs, liver, spleen, heart and kidney were congested. Intestine, rectum and colon were hemorrhagic. Clay colored material was found in colo-rectum. Purulent exudates in lungs and thick and cloudy pericardial fluid in pericardial sac were found. Histologically, multifocal granulomatous inflammation was evident in lung, liver, kidney, intestine and colon with bacterial colonies, fungal spores and hyphae. These bacteria were appeared as Gram negative. Fungal hyphae and spores were detected in liver, lungs and colon by using PAS stain. Bacteriologically, E. coli were isolated from lungs exudates, pericardial fluids and intestinal fluids. Therefore, it can be concluded that 3 crocodiles died due to E. coli septicemia concurrent with mycotic infection.