Morphometric characteristics of diploid and triploid Far Eastern catfish, Silurus asotus

Park, In-Seok Korean Society of Environmental Biology 2020 환경생물 : 환경생물학회지 Vol.38 No.1

This study identified the differences in the morphometric characteristics of the truss and classical dimensions between diploid and triploid Far Eastern catfish, Silurus asotus, and provided methods for sorting diploid and triploid Far Eastern catfish based on morphometric observations. The significant variables were the direct distance between the anterior edge of the lower lip and the anterior insertion of the dorsal fin(DALAD), the horizontal distance between the anterior edge of the lower lip and the anterior insertion of the ventral fin (HALAV), the direct distance between the anterior edge of the upper lip and the first nostril(DAUF), the direct distance between the anterior edge of the upper lip and the second nostril(DAUS), the interorbital width(IW), and the mandible barbel length (ManBL). The more significant variables were HALAV, DALAD, DAUF, IW, and DAUS. The most useful combination of variables for separating the two groups was DALAD, IW, and DAUF, which correctly classified 85% of the catfish as triploid or diploid, and that percentage was the maximum degree of value possible (p<0.05). Triploid Far Eastern catfish had a high rate of growth in the head region and body depth during the first year after hatching. Triploid Far Eastern catfish had smaller heads and shorter mandible barbels than diploid Far Eastern catfish.

메기, Silurus asotus 사료의 어분 대체 단백질원으로 대두박 및 실용사료 사육효능 평가

김경덕,임상구,황주애,김진도,강용진 한국수산과학회 2009 한국수산과학회지 Vol.42 No.4

Two feeding trials were conducted to evaluate the soybean meal as a substitute for the fish meal in diet (experiment Ⅰ), and experimental practical diet and commercial diet (experiment Ⅱ) for growth of far eastern catfish. In the experiment I, three replicate groups of juveniles (average weight 7.2 g) were fed one of diets containing 0, 10 and 20% soybean meals for 66 days. Survival and final mean weight were not significantly affected by dietary soybean meal levels. No significant differences were observed in feed efficiency, protein efficiency ratio and protein retention of fish fed between 0% (control diet) and 20% soybean meal diets. However, fish fed 10% soybean meal diet showed the lower feed efficiency, protein efficiency ratio and protein retention, and higher daily feed intake compared with fish fed control diet and 20% soybean meal diet. The contents of moisture, crude protein, crude lipid and ash in the whole body were not significantly affected by dietary soybean meal levels. In the experiment Ⅱ, three replicate groups of juveniles (average weight 7.3 g) were fed either the formulated diet or commercial diet for 66 days. Survival and final mean weight were not significantly different among treatment. Significantly higher feed efficiency, protein efficiency ratio and protein retention, and lower daily feed intake were observed in fish fed experimental practical diet compared with fish fed commercial diet (P<0.05). Proximate compositions of the whole body were not significantly affected by diets. The results of these studies suggest that soybean meal can be used as a substitute for fish meal up to 20% in diet, and the dietary formulation used in the experiment Ⅱ could be applied to the practical feed for far eastern catfish.

메기(Silurus asotus) 기아 시 외부형태 및 체 절단면 변화

박인석,구인본,길현우,Park, In-Seok,Goo, In Bon,Gil, Hyun Woo 한국환경생물학회 2021 환경생물 : 환경생물학회지 Vol.39 No.1

메기(Silurus asotus)를 대상으로 210일간 기아 시 계측형질 및 체 절단면 형질을 측정하여 그 기아 효과를 조사하였다. 실험 종료시 섭이군의 생존율은 92.2±0.47%였으며, 기아군에서는 74.4±2.59%의 생존율을 보였다. Ls, DALPO/Ls, DADOP/Ls, ED/Ls, CH/Ls, BDAA/Ls, BDMA/Ls 및 BWAA/Ls의 8개 항목에서 유의한 차이를 보였으며(p<0.05), 다른 16개 항목 DALAD/Ls, DPDPL/Ls, HPLAA/Ls, HALAV/Ls, HALOP/Ls, DAUPO/Ls, DADAV/Ls, DADAA/Ls, Max BL/Ls, Man BL/Ls, LD/Ls, HWOP/Ls, DAUF/HL, DAUS/HL, IW/HL 및 DAUE/HL에서는 초기군, 섭이군 및 기아군의 세 그룹 간 유의한 차이가 없었다(p>0.05). 섭이군은 각 체 절단면에서 기아군보다 더 높은 전체 높이(THX), 더 넓은 너비(WX) 및 더 넓은 면적(AX)을 보였다. 본 연구는 메기의 기아 상태에 대한 외형 및 체 절단면 형질에 대한 정보를 제공한다. 이는 메기에 대한 먹이 조절에 대한 방법을 보조하고 영양상태를 나타내는 기본 기초자료로 활용될 수 있을 것이다. 또한, 본 연구에서 사용한 조사 분석 방법을 타 어종에서 적용 시 그 영양 상태에 대한 정보를 파악하는 데 유용하게 활용될 수 있을 것으로 사료된다. A 210-day experiment was conducted to examine the effects of starvation on survival, external morphometric traits, and sectioned morphometric traits in Far Eastern catfish(Silurus asotus). The survival rate decreased to 92.2±0.47% in the fed group and to 74.4±2.59% in the starved group. Eight dimensions of Ls, DALPO/Ls, DADOP/Ls, ED/Ls, CH/Ls, BDAA/Ls, BDMA/Ls, and BWAA/Ls showed significant differences (p<0.05), and 16 other dimensions of DALAD/Ls, DPDPL/Ls, HPLAA/Ls, HALAV/Ls, HALOP/Ls, DAUPO/Ls, DADAV/Ls, DADAA/Ls, Max BL/Ls, Man BL/Ls, LD/Ls, HWOP/Ls, DAUF/HL, DAUS/HL, IW/HL, and DAUE/HL were not significantly different among the initial, fed, and starved groups (p>0.05). The fed group showed higher total height (THX), wider width (WX), and larger area (AX) than those of the starved group in each body section. This research provides information on the morphometric traits and body sections of starved Far Eastern catfish. These results can be used as a basic guide to indicate nutritional status and assist in aquaculture methods for Far Eastern catfish. Moreover, the methods used in this study were considered helpful because the survey analysis method can be used to investigate information on the nutritional status of other fish species.

Morphometric characteristics of diploid and triploid far eastern catfish, Silurus asotus

In-Seok Park,Hyun Woo Gil,In Bon Goo 한국발생생물학회 2013 한국발생생물학회 학술발표대회 Vol.2013 No.8

The present study determined the differences in the morphometric characteristics of truss and classical dimensions between diploid and triploid Far Eastern catfish, Silurus asotus and provided methods for separating diploid and triploid Far Eastern catfish based on morphometric observations. Significant variables were the direct distance between the anterior edge of the lower lip and the anterior insertion of the dorsal fin (DALAD), the horizontal distance between the anterior edge of the lower lip and the anterior insertion of the ventral fin (HALAV), the direct distance between the anterior edge of the upper lip and the first nostril (DAUF), the direct distance between the anterior edge of the upper lip and the second nostril (DAUS), the interorbital width (IW), and the mandible barbel length (ManBL). The more significant variables were DALAD, HALAV, DAUF, DAUS, and IW. The most useful combination of variables for separating the two groups was DALAD, IW, and DAUF, which correctly classified 85% of the catfish as triploid or diploid, the maximum degree of separation obtained (P<0.05). The triploid catfish had high head region and body depth growth rates during the first year after hatching. Triploid catfish had smaller heads and shorter mandible barbels than diploid catfish.

메기(Silurus asotus) 기아 시 조직학적 변화

구인본,김영수,박인석,Goo, In Bon,Kim, Young Soo,Park, In-Seok 한국환경생물학회 2020 환경생물 : 환경생물학회지 Vol.38 No.2

메기(Silurus asotus)의 기아 시 생존율, 생식소 중량지수(gonadosomatic index; GSI), 간 중량지수(hepatosomatic index; HSI) 및 장 중량지수(intestinosomatic index; ISI)와 신장세포, 장 상피세포 및 간세포의 조직학적 변화를 조사하였다. 생존율은 섭이군이 92.2±0.47%, 기아군이 74.4±2.59%를 보였으며, GSI, HSI 및 ISI는 기아군에서 가장 낮은 값을 나타내었다(p<0.05). 신장세포 핵의 높이, 장 상피세포 핵의 높이, 간세포 핵의 크기 및 간세포의 크기는 섭이군에서 가장 높은 값을 보였으며(p<0.05), 신장세포핵의 높이, 장 상피세포 핵의 높이 및 간세포 핵의 크기는 기아군에서 가장 낮은 값을 보였다(p>0.05). 멜라닌대식세포(melano-macrophages; MMs)는 기아 동안 신장에서 증가함을 관찰하였다. 신장의 MMs 증가 및 간세포의 수축현상은 메기의 기아 상태를 식별하는 지표로 이용할 수 있으며, 본 연구의 결과는 메기의 영양 상태 확인을 위한 기초 자료로서 의미가 있을 것으로 사료된다. A 210-day experiment was conducted to examine the effects of starvation on survival, the gonadosomatic index (GSI), hepatosomatic index (HSI), and the intestinosomatic index (ISI), and histological changes in the renal tubule epithelium, midgut epithelium, and hepatocytes in Far Eastern catfish (Silurus asotus). The survival rate decreased to 92.2±0.47% in the fed group and 74.4±2.59% in the starved group during the 210-day experimental period. GSI, HSI, and ISI were lowest in the starved group (p<0.05). The hepatocyte nuclear area, hepatocyte cell area, the nuclear height of the midgut epithelium, and the nuclear height of the kidney were highest in the fed group (p<0.05). The hepatocyte nuclear area, nuclear height of the midgut epithelium, and nuclear height of the kidney were lowest in the starved group(p<0.05). The numbers of melano-macrophages (MMs) found in the kidney cells increased during starvation in this species. This suggests that thinner body cavity regions, the contraction of hepatocyte nuclear sites, and the spreading of kidney cell MMs in this species could be used as alternative indicators for identifying starvation conditions. Therefore, the results from our study provide accurate indications of the nutritional status of Far Eastern catfish.

메기 Silurus asotus용 실험 배합사료와 상품사료의 사육효능 비교

임상구,김광석,강용진,김응오,손맹현,안철민,김강웅,조용철,김경덕 한국수산과학회 2012 한국수산과학회지 Vol.45 No.2

Two feeding trials were conducted to evaluate the effects of experimental extruded pellets (EEPs) and commercial EPs (CEPs) on Far Eastern catfish Silurus asotus in pilot- (experiment I) and commercial-scale (experiment II) tanks. Four diets were prepared: three EEPs (EEP1, EEP2 and EEP3) that contained different amounts of tuna fish meal, soybean meal, and squid liver oil, and one CEP diet. In experiment I, three replicate groups of juveniles were fed one of the four EPs in pilot-scale tanks for 19 weeks. The weight gains (WGs) of fish fed EEP1 and CEP were significantly higher than those of fish fed EEP2 or EEP3. The highest feed efficiency (FE) was observed in fish fed the CEP diet (P<0.05), and the FE of fish fed EEP1 and EEP3 were significantly higher than that with EEP2 (P<0.05). In experiment II, juveniles were fed one of four EPs in commercial-scale tanks for 19 weeks. WG and FE values of fish fed EEP1 and CEP were higher than those of fish fed EEP2 and EEP3. The results of this study indicate that the dietary formulation used in EEP1 could be used as a practical feed for Far Eastern catfish.

The Effect of Sodium Nitrite Exposure on Physiological Response of Starved Far Eastern Catfish, Silurus asotus

박인석,Hyun Woo Gil 한국발생생물학회 2018 발생과 생식 Vol.22 No.4

The experiment was conducted for 210 days to determine the effect of feeding, and starvation, and exposure to sodium nitrite (NaNO2) on the survival, physiological changes, hematological parameter, and stress response of Far Eastern catfish, Silurus asotus. The survival of the starved group was lower than that of the fed group during the experiment. Starva-tion resulted in retardation of growth, which provides an example of fish that failed to continue to grow and remain in a good condition. Blood analyses (cortisol and glucose) showed significant differences of stress response between the fed and starved groups exposed to NaNO2 at the conclusion of the experiment (p<0.05). These results suggest that all nutritional parameters used for starvation and feeding with NaNO2 stress in this experiment appear to be a useful index of nutritional status in Far Eastern catfish.

The Effect of Sodium Nitrite Exposure on Physiological Response of Starved Far Eastern Catfish, Silurus asotus

Park, In-Seok,Gil, Hyun Woo The Korean Society of Developmental Biology 2018 발생과 생식 Vol.22 No.4

The experiment was conducted for 210 days to determine the effect of feeding, and starvation, and exposure to sodium nitrite ($NaNO_2$) on the survival, physiological changes, hematological parameter, and stress response of Far Eastern catfish, Silurus asotus. The survival of the starved group was lower than that of the fed group during the experiment. Starvation resulted in retardation of growth, which provides an example of fish that failed to continue to grow and remain in a good condition. Blood analyses (cortisol and glucose) showed significant differences of stress response between the fed and starved groups exposed to $NaNO_2$ at the conclusion of the experiment (p<0.05). These results suggest that all nutritional parameters used for starvation and feeding with $NaNO_2$ stress in this experiment appear to be a useful index of nutritional status in Far Eastern catfish.

Effects of Cryoprotectants and Diluents on the Cryopreservation of Spermatozoa from Far Eastern Catfish, Silurus asotus

Gil, Hyun Woo,Lee, Tae Ho,Park, In-Seok The Korean Society of Developmental Biology 2017 발생과 생식 Vol.21 No.1

The aim of this study was to compare the efficacy of cryopreservation methods for ex situ conservation of spermatozoa from far eastern catfish, Silurus asotus. The spermatozoa activity index (SAI) and hatching rates were higher in spermatozoa stored in Alserver's solution than those of spermatozoa stored in glucose solution. The SAI and hatching rates in all experimental groups gradually decreased with increasing duration of storage. Additionally, the SAI and hatching rates gradually decreased with increasing thawing temperatures at all storage durations (P<0.05). Based on the SAI and hatching rates, our results suggest that the optimal cryopreservation conditions of catfish spermatozoa involve storage in Alserver's solution with 15% ethylene glycol, and thawing at $25^{\circ}C$. Cryopreservation of spermatozoa is a useful and reliable technique for conserving gene resources and for artificial propagation of far eastern catfish.

Effects of Dietary Protein and Lipid Levels on Growth and Body Composition of Juvenile Far Eastern Catfish Silurus asotus

Kim, Kyoung-Duck,Lim, Sang-Gu,Kang, Yong-Jin,Kim, Kang-Woong,Son, Maeng-Hyun Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.3

A $3{\times}2$ factorial experiment was conducted to determine the effects of dietary protein and lipid levels on the growth and body composition of juvenile far eastern catfish. Six diets were formulated to contain three levels of protein (20%, 30% and 40%) and two levels of lipid (9% and 17%). Triplicate groups of fish (initial body weight of 7.6 g) were hand-fed to apparent satiation for 66 days. Final mean weight was improved with increasing dietary protein and lipid levels, and the highest final mean weight was observed in fish fed the 40/17 (% protein/% lipid) diet. No significant difference was observed in final mean weight for fish fed between 30/17 diet and 40/9 diet. Feed efficiency of fish fed the diets containing over 30% protein levels with 9% and 17% lipid levels were significantly higher than those of fish fed the 20% protein levels. Feed efficiency of fish fed the 30/17 diet was not significantly different from that of fish fed the 40/9 diet or 40/17 diet. Feed efficiency and protein efficiency ratio of fish fed the 20% protein diets with 17% lipid level were significantly higher than those of fish fed 9% lipid diet. Daily feed intake of fish tended to decrease with increasing dietary protein and lipid levels. Moisture content of whole body in fish fed the 9% lipid diets was significantly higher than that of fish fed the 17% lipid diets at the same protein level, but the opposite trends were found for crude lipid content. Significant effects of dietary lipid were observed for most fatty acids, according to their relative values in the diets. The results of this study suggest that the protein requirement for maximum growth of juvenile far eastern catfish may be higher than 40%, and an increase of dietary lipid level from 9% to 17% can improve growth and feed utilization.