The Effects of Starvation on Physiological Changes and Stress Response in Cultured Cobitid Loach (Misgurnus anguillicaudatus) Exposed to Sodium Nitrite

Hur, Jun Wook,Gil, Hyun Woo,Park, In-Seok The Korean Society of Marine Life Science 2018 한국해양생명과학회지 Vol.3 No.2

To investigate effects of starvation on physiological changes, stress response, and survival of cobitid loach (Misgurnus anguillicaudatus) exposed to sodium nitrite (NaNO₂), a 4-week experiment was conducted. Fewer fish survived in the starved group than those in the fed group during the experiment. Starvation resulted in growth retardation, leading to differences in body length and body depth between fed and starved groups. The fed gorup continued to grow and remained in good condition. Blood chemical analysis (plasma cortisol and glucose) showed significant differences in stress response to nitrite exposure between fed and starved groups (p < 0.05). These results suggest that all parameters employed in this study to assess effects of starvation with NaNO₂ stress are useful information for researching nutritional status in cobitid loach.

Comparison of Ecological Properties between Agricultural Reservoirs Situated in Forest and Urban Areas

( Jun Wook Hur ),( Youngsung Kim ),( Yongeun Park ),( Jae-ki Shin ) 한국물환경학회(구 한국수질보전학회) 2019 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2019 No.-

Assessment of Physical Habitat and the Fish Community in Korea Stream

Jun Wook Hur,Jin Chul Joo,Byungwoong Choi 응용생태공학회 2022 Ecology and resilient infrastructure Vol.9 No.1

The purpose of this study is to provide essential data necessary to assess ecological flow requirements by understanding habitat conditions for fish species through monitoring an ecological environment in the Korea stream (Dal Stream) and building related database. On-site surveys were conducted for identifying ecological and habitat conditions at the four monitoring sites. Fish sampling was carried out at the selected four sites (St.) during the period ranging from September, 2008 to September, 2009. At the four sampling sites, we measured water surface elevation, depth and velocity at the cross-sections. Optimal Ecological Flowrates (OEFs) were estimated using the Habitat Suitability Index (HSI) established for four fish species Zacco koreanus (St.1), Pungtungia herzi (St.2), Coreoleuciscus splendidus (St.3), and Zacco platypus (St.4) selected as icon species using the Physical HABitat SIMulation system (PHABSIM). Eighteen species (56.3%) including Odontobutis interrupta, Coreoperca herzi and C. splendidus were found endemic out of the 32 species in eight families sampled during this study period. The endangered species was collected Acheilognathus signifier, Pseudopungtungia tenuicorpa and Gobiobotia macrocephala, and this relative abundance was 9.4%. The most frequently found one was Z. platypus (31.3%) followed by C. splendidus (17.6%) and Z. koreanus (15.7%). The estimated IBI values ranged from 27.3 to 34.3 with average being 30.3 out of 50, rendering the site ecologically poor to fair health conditions. For C. splendidus (St.3), the dominant fish species in the stream, the favored habitat conditions were estimated to be 0.3-0.5 m for water depth, 0.4-0.7 m/s for flow velocity and sand-cobbles for substrate size, respectively. An OEFs of 8.5 m3/s was recommended for the representative fish species at the St.3.

Physiological Responses to Three Different Levels of Vibration Stress in Catfish, Silurus asotus

Jun Wook Hur,Dae Hee Kim,Jeong-Yeol Lee 응용생태공학회 2015 Ecology and resilient infrastructure Vol.2 No.4

The purpose of this study is to determine the effects of vibration on primary (e.g. plasma cortisol), secondary (e.g. plasma glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), Na<SUP>+</SUP>, K<SUP>+</SUP> and Cl–) and tertiary (e.g. mortality) stress responses in cultured catfish, Silurus asotus. For this purpose, three groups (one control group and two stress groups) were set up. The control group was exposed to vibration corresponding to 48 decibel (dB) volt (V) (produced using electric vibrators) for 15 minutes per hour every day, and the two stress groups were exposed to vibrations corresponding to 58 and 68 dB (V) (produced using the same electric vibrators), equally, for 15 minutes per hour every day. Blood was sampled at day 0 (before starting vibration stress tests), and at days 1, 3, 5, 7, 9 and 11 (after starting vibration stress tests). According to the results, the catfish physiologically showed ""typical"" stress responses when they were exposed to chronic vibration. This indicates that such chronic vibration caused substantial stress to catfish; especially, persistently elevated plasma AST and ALT levels observed caused adverse effects to them. In conclusion, chronic vibration could significantly affect hematological characteristics in catfish.

Physiological Responses to Three Different Levels of Vibration Stress in Catfish, Silurus asotus

Hur, Jun Wook,Kim, Dae Hee,Lee, Jeong-Yeol Korean Society of Ecology and Infrastructure Engin 2015 Ecology and resilient infrastructure Vol.2 No.4

The purpose of this study is to determine the effects of vibration on primary (e.g. plasma cortisol), secondary (e.g. plasma glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), $Na^+$, $K^+$ and $Cl^-$) and tertiary (e.g. mortality) stress responses in cultured catfish, Silurus asotus. For this purpose, three groups (one control group and two stress groups) were set up. The control group was exposed to vibration corresponding to 48 decibel (dB) volt (V) (produced using electric vibrators) for 15 minutes per hour every day, and the two stress groups were exposed to vibrations corresponding to 58 and 68 dB (V) (produced using the same electric vibrators), equally, for 15 minutes per hour every day. Blood was sampled at day 0 (before starting vibration stress tests), and at days 1, 3, 5, 7, 9 and 11 (after starting vibration stress tests). According to the results, the catfish physiologically showed ''typical'' stress responses when they were exposed to chronic vibration. This indicates that such chronic vibration caused substantial stress to catfish; especially, persistently elevated plasma AST and ALT levels observed caused adverse effects to them. In conclusion, chronic vibration could significantly affect hematological characteristics in catfish.

Changes of Morphometric Traits in the Cultured Cyprinid Loach (Misgurnus anguillicaudatus) to Starvation

Jun Wook Hur,Hyun Woo Gil,In-Seok Park 응용생태공학회 2018 Ecology and resilient infrastructure Vol.5 No.4

The experiment was conducted to investigate the effects of various dietary conditions on external morphometric traits, and sectioned morphometric traits in the cultured cyprinid loach, (Misgurnus anguillicaudatus) for 28 days. For the fed group there was an increase in body weight, standard length, and morphometric dimensions of the head and body cavity regions compared with the starved and initial groups. Sectioned morphometric trait analysis revealed that relative to the starved group, the fed group had greater body circumference, cross-sectional area, and total height (P<0.05). Our results provide data on external and sectioned morphometric changes under starvation conditions, and can be used as a guide to assist in the regulation and scheduling of feeding, and as indices of the nutritional status of cyprinid loach.

Changes of Morphometric Traits in the Cultured Cyprinid Loach (Misgurnus anguillicaudatus) to Starvation

Hur, Jun Wook,Gil, Hyun Woo,Park, In-Seok Korean Society of Ecology and Infrastructure Engin 2018 Ecology and resilient infrastructure Vol.5 No.4

The experiment was conducted to investigate the effects of various dietary conditions on external morphometric traits, and sectioned morphometric traits in the cultured cyprinid loach, (Misgurnus anguillicaudatus) for 28 days. For the fed group there was an increase in body weight, standard length, and morphometric dimensions of the head and body cavity regions compared with the starved and initial groups. Sectioned morphometric trait analysis revealed that relative to the starved group, the fed group had greater body circumference, cross-sectional area, and total height (P<0.05). Our results provide data on external and sectioned morphometric changes under starvation conditions, and can be used as a guide to assist in the regulation and scheduling of feeding, and as indices of the nutritional status of cyprinid loach.

하천에서 보 형태에 따른 어류군집 구조 및 생태유량 평가

허준욱(Jun Wook Hur),장창래(Chang Lae Jang),김규호(Kyu Ho Kim) 大韓環境工學會 2017 대한환경공학회지 Vol.39 No.6

본 연구는 원주천과 보성강에서 보의 형태에 따른 어류 군집 구조를 파악하고, 보를 중심으로 상하류에 PHABSIM을 이용한 최적 생태유량을 산정하여 물리적 서식지 평가를 실시하였다. 2014년 8월부터 2015년 9월까지 원주천의 콘크리트보(반곡보) 6회, 보성강의 돌보는 5회 조사를 실시하였다. 어류는 투망과 족대를 이용하여 채집하였으며, 어류를 채집한 지점에서 유속, 수심, 하상재료를 측정 및 관찰하였다. 어류상을 토대로, 생물다양도(우점도, 균등도, 다양도, 풍부도)를 측정하였으며, PRIMER5를 통해 군집유사도를 산출하였고, PHABSIM을 이용하여 최적 유량을 산정하였다. 원주천에서는 7과 20종 2,104개체가 채집되었으며 피라미와 참갈겨니가 각각 39.7%, 15.8%로 우점 및 아우점하였다. 보성강에서는 6과 28종 1,638개체가 출현하였고, 피라미와 돌마자가 각각 22.0%, 17.2%로 우점 및 아우점하였다. 서식지적합도지수(Habitat Suitability Index, HSI)를 산정하기 위해 두 지점의 대표어종인 피라미를 선정하였다. 그 결과 원주천에서는 수심 0.2~0.6 m 유속 0.1~0.3 m/s로 측정되었고, 보성강에서는 수심 0.3~0.6 m, 유속 0~0.3 m/s로 나타났다. PHABSIM을 이용한 최적 생태유량 모의 결과 원주천의 보상류가 1.1 cms, 하류가 0.3 cms, 보성강은 상류가 0.4 cms, 하류가 2.2 cms로 나타나 각각의 하천에서 반대의 결과가 나타났다. 최적유량 적용시 가중가용면적(Weighted Usable Area, WUA)는 원주천이 상류 9.5%, 하류 26.6%, 보성강은 상류 34.8%, 하류 53.3%로 나타났다. The objectives of this study were to analyze ecological characteristics of fish compositions and estimate the optimal ecological flow using the physical habitat simulation system (PHABSIM) in Wonju stream and Boseong river. We sampled fishes using two gears such as casting net and kicknet to determine fish distribution and also measured flow velocity, water depth, bed material at the point where fish collected. Total number of species and individuals sampled were 20 and 2,104, respectively and dominant species was Zacco platypus (39.7%) and subdominant species was Z. koreanus (RA: 15.8%) in Wonju stream. In Boseong river, collected fishes were 1,638 individuals, 28 species. Dominant and sub-dominant species was Z. platypus (RA: 22.0%) and Microphysogobio yaluensis (RA: 17.2%), respectively. For calculating habitat suitability index (HSI), we selected Z. platypus as representative fish species and analyzed water depth and flow velocity. Water depth and flow velocity were 0.2-0.6 m, 0.1-0.3 m/s, respectively in Wonju stream and 0.3-0.6 m, 0-0.3 m/s, respectively in Boseong river. According to the analysis of ecological flow simulation, optimal flow was 1.1 cms and 0.3 cms in Wonju stream and 0.4cms, 2.2cms in Boseong river at up and down stream respectively. WUA (Weighted Usable Area) was 9.5%, 26.6% in Wonju stream and 34.8%, 53.3% in Boseong river at up and down stream respectively.

사육수의 담수화시 수용밀도에 따른 넙치(Paralichthys olivaceus)의 생리적 반응 비교

허준욱 ( Jun Wook Hur ),이복규 ( Bok Kyu Lee ),민병화 ( Byung Hwa Min ),박인석 ( In Seok Park ),최철영 ( Cheol Young Choi ),이정열 ( Jeong Yeol Lee ),장영진 ( Young Jin Chang ) 한국환경생물학회 2004 환경생물 : 환경생물학회지 Vol.22 No.3

사육수의 담수화시 수용밀도에 대한 생리학적 반응을 비교하고자, 30마리와 60마리씩 실험수조에 수용하여 30분이내에 사육수를 담수로 교환하였다. 혈장의 Cortisol농도는 실험개시시 30SW에서 2.8 ng mL^(-1), 60SW는 2.7 ngL^(-1)로부터 30FW와 60FW는 24시간째 각각 66.9 ng mL^(-1), 314.1 ng mL^(-1)로 유의하게 높아졌다. 혈장의 Glucose 농도는 60SW는 개시시 15.8 mg dL^(-1)로부터 60FW는 3시간째 257.7 mg dL^(-1), 24시간째 164.0 mg dL^(-1)로 개시시보다 농은 값으로 남아있었다. Na^+ 농도는 30SW와 60SW는 시간경과에 따라 차이를 보이지 않았으나, 30FW와 60FW는 시간경과에 따라 낮아지는 경향을 보였다. Cl^-농도는 60FW에서 개시시 59.0 mEq L^(-1)로부터 3시간과 24시간째에 각각 43.5 mEq L^(-1), 30.0 mEq L^(-1)로 유의하게 낮아진 값을 보였다. 모든 실험구에서 생존율은 100%였다. 사육수를 24시간동안 담수로 교환시 사육밀도의 차이에 따른 혈장과 혈액학적 지표에서 다소 차이를 나타냈으며, 삼투압 조절 능력 및 생존율에서는 해수에서와 같은 경향을 보였다. Two different groups (30 and 60 inds.) of olive flounder (Paralichthys olivaceus) were abruptly (within 30 min) exposed to hypo- salinities from seawater (SW, 35‰) to freshwater (FW, 0‰) (30FW and 60FW) and to 35‰ (30SW and 60SW) in a flow through seawater culture systems. Analysis of plasma samples showed the following significant increase at 0‰: cortisol from 2.8 ng mL^(-1) to 66.9 ng mL^(-1)(30FW) and from 2.7 ng mL^(-1) to 314.1 ng mL^(-1)(60FW) after 24 hours of exposure; glucose from 15.8 mg dL^(-1) to 257.7 mg dL^(-1) after 3 hours exposure and to 164.0 mg dL^(-1) after 24 hours in 60FW. Plasma Na^+ concentration of 30FW and 60FW were decreased until 24 hours after expose. However that in 30SW and 60SW showed no significant differences. Plasma Clconcentration of 60FW was decreased from 59.0 mEq L^(-1) to 43.5 mEq L^(-1) and to 30.0 mEq L^(-1) after 3 and 24 hours of exposure, respectively. At all experimental groups, survival were 100% until 24 hours.

금강수계 미호천에 서식하고 있는 유영성 어종의 서식지적합도지수 산정

허준욱(Jun Wook Hur),김경훈(Kyung Hoon Kim),이종진(Jong Jin Lee) 응용생태공학회 2021 Ecology and resilient infrastructure Vol.8 No.1