• 한국수산과학회지
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• 제37권6호
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• pp.462-468
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• 2004

In order to evaluate adaptation to the environment in released fish, digestive organ and body composition were compared among 1-year old cultured (CUL), released (REL) and wild (WIL) Black Sea Bream, Acanthopagrus schlegeli. Hepatosomatic index (HSI) of the REL was significantly lower than those of the CUL and WIL fish, but intestine weight index (IWI) of REL was significantly higher than those of the CUL and WIL fish. There were no significant differences in stomach weight index (SWI) and condition facto. (CF) among those different fish groups. The number of pyloric caeca of the REL and WIL fish were 4, but the $30{\%}$ of CUL fish was 3 counts. The moisture content of whole body in the WIL fish was significantly higher than the CUL and REL fish, but significant lowest in the crude lipid of whole body. The content of moisture and crude protein of dorsal muscle were no significant differences among the CUL, REL and WIL fish, but crude lipid content of WIL fish was significantly lower than the CUL and REL fish. Moisture content of CUL fish in the liver was significantly lower than the REL and WIL fish, and crude lipid was significant lowest in the WIL fish. Amino acid content of dorsal muscle in the WIL fish was highest in the total amino acid, EAA and E/A ratio, and CUL fish was highest EAA and E/A ratio in liver. EPA content in dorsal muscle of WIL fish was lower than CUL and REL fish, and the REL fish was highest in DHA content of the fatty acid. EPA content in liver of WIL fish was lower than CUL and REL fish, and DHA content in REL and WIL fish was highest and lowest. Crude protein content of CUL and WIL fish in the scale was significantly higher than REL fish, but there were no significant differences in contents of crude lipid and ash. Ca and P of scale were formed most of mineral and content of P in CUL fish was significantly higher than those of REL and WIL fish. There were no significant differences in Mg, K, Na and S of scale, but CUL fish was significantly lower than REL fish in C1. The results suggest that difference of digestive organs and body composition concluded it from differences of inhabitation environment and feed formulations.

• 한국임상수의학회지
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• 제19권1호
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• pp.1-6
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• 2002

We evaluated the wholesomeness of fish feeds treated with high-dose radiation. This study examined the safety of fish fed treated with high-dose irradiation (5 kGy) and butylated hydroxyanisole (BHA, 200 ppm). 100 flounder (Paralichthys olivaceus) were grouped into 4 and then the fishes fed the following feeds for 28 days: (1)standard feed; (2)standard feed, treated with BHA; (3)standard feed, irradiated to 5 kGy; (4)standard feed, treated with BHA and irradiated to 5 kGy. Four groups each 10 mice were fed the fish feeds same as (1)-(4) for 14 days. There were no observable differences between fishs fed the irradiated feed and those fed the standard feed with respect to growth, feed consumption, haematology and organ histopathology Parameters. There were no deviations in feed consumtion, haematology and organ histopathology parameters in the experiment of mice. We concluded that there were no irradiation-related effects.

• 한국양식학회지
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• 제19권3호
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• pp.178-182
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• 2006

이 연구에서는 해산어 초기 자어 사육 과정에서 자어가 섭이하는 로티퍼의 새로운 관찰 및 계수방법을 제시한다. 지금까지는 해산어 자어를 사육하면서 언제부터 로티퍼를 먹이로 이용 가능한지? 그리고 일령이 경과함에 따라 어느 정도 양의 로티퍼를 섭이하는지? 정확하게 분석할 수는 없었다. 왜냐하면 자어가 섭이한 로티퍼(몸통)는 소화기관내에서 소화되어 연구자가 관찰할 수 없었기 때문이다. 그러나 이 연구에서는 이러한 문제점을 해결할 수 있는 새로운 관찰 방법으로서 로티퍼의 저작기(trophi)를 이용하는 방법을 제시한다. 로티퍼는 각 개체마다 한개의 저작기를 가지며 이 저작기는 해산어 자어의 소화기관내에서도 소화되지 않고 그 형태를 유지한다. 따라서 이 연구 결과에 의하면 자어의 소화기관내의 저작기를 관찰하여 계수하는 방법(RTCM; Rotifer Trophi Counting Method)을 이용하여 로티퍼를 최초로 섭이하는 일령은 물론 자어의 일령이 경과함에 따른 포식 로티퍼 개체수를 정확하게 분석할 수 있다.

• 한국환경생태학회지
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• 제34권4호
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• pp.282-293
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• 2020

본 연구에서는 2009-2019년 기간 동안 대전시 외곽의 도심개발에 따른 인근 하천(관평천)의 상류, 중류, 하류의 구간에서 4회 조사(2009, 2010, 2016, 2019)를 통해 이화학적 수질, 어류 종 조성, 생태 건강성 특성에 대해 장기간 변화추이를 분석하였다. 본 하천지역에서 도심개발은 2008년에 이루어졌고, 2012년에는 하천복원사업이 수행되어 하천복원 전과 후의 특성변화 추이를 모니터링 하였다. 하천 생태건강도 평가를 위해 군집수준의 어류평가지수(Fish Assessment Index, FAI)를 이용하였고, 어류의 기관(Organ) 수준에서 해부학적 건강도(Necropsy-based Health Assessment Index, HAI) 분석을 실시하였다. 이화학적 수질 분석에서는 중류(St. 2)에서 가장 낮은 탁도와 엽록소(Chl-a)가 측정되었다. 이는 빠른 유속에 의한 물리적 요인 때문으로 나타났다. 어류 조사에서는 총 18종이 채집되었고, 피라미(Zacco platypus)가 가장 우점 하는 종(40.6%)으로 나타났다. 하천복원 직후(2016)에는 민감종(Sensitive species)과 충식종(Insectivore species)이 우점, 종 다양도 및 종 풍부도 지수 상승, 생태건강도 지수(FAI)가 상승하여 생태 건강도는 "최상상태(A: 87.5)"로 나타났으나 가장 최근 조사인 2019년에는 전 기간에 비해 악화되는 것으로 나타났다. 기관(Organ) 분석에 의거한 해부학적 건강도 지수(HAI) 분석에 따르면, 피부손상(Skin)은 상류에서, 신장 손상(Kidney)은 하류 역에서 나타났고, 간(Liver)과 아가미(Gill)의 손상은 모든 지점에서 나타나 해부학적 측면의 건강도에서도 영향을 받는 것으로 나타났다.

• Animal Bioscience
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• 제34권7호
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• pp.1181-1192
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• 2021

Objective: The objective of the current study was to investigate the effects of dietary hatchery by-products (HBPs) as a replacement of fish meal (FM) on growth performance, relative organ weight, plasma measurements, immune organ index, meat quality, and tibia characteristics of broiler chickens. Methods: A total of 720 broiler chickens (3 d of age) were randomly allotted to 1 of 9 treatments with 8 replicates. Each replicate consisted of 5 male and 5 female birds. The basal diet was formulated to contain 5.0% commercial FM, whereas eight treatment diets were prepared by replacing 25%, 50%, 75%, or 100% of FM in the basal diet with infertile eggs (IFE) or a mixture of various HBPs (MIX); therefore, the inclusion levels of IFE or MIX in the experimental diets were 1.25%, 2.50%, 3.75%, or 5.00%. The diets and water were provided on an ad libitum basis for 32 d. Results: Increasing inclusion levels of IFE as a replacement of FM in diets had no effects on growth performance, plasma measurements, immune organ index, and tibia characteristics of broiler chickens. Increasing inclusion levels of IFE in diets increased (linear, p<0.05) meat lightness (L^*) but decreased (linear, p<0.05) meat redness (a^*). The breast meat pH at 1-h postmortem was increased (linear, p<0.05) by increasing inclusion levels of IFE in diets. Likewise, increasing inclusion levels of MIX in diets had no effects on growth performance, relative organ weight, plasma measurements, immune organ index, and tibia characteristics. However, increasing inclusion levels of MIX in diets increased (linear, p<0.05) 1-h postmortem pH but decreased (linear, p<0.05) 24-h postmortem pH of breast meat. Increasing inclusion levels of MIX in diets decreased (linear, p<0.05) thiobarbituric acid reactive substances values of breast meat. Conclusion: Both IFE and MIX are suitable alternatives to FM as protein ingredients in broiler diets.

• 제어로봇시스템학회논문지
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• 제21권10호
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• pp.924-929
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• 2015

In this paper, we suggest a phase difference algorithm inspired by weakly electric fish. Weakly electric fish is a fish which generates electric field though its electric organ in the tail. The weakly electric fish search for prey and detect an object by using electrolocation. The weakly electric fish have Jamming Avoidance Response (JAR) to avoid jamming signal. One of pulse-type weakly electric fish Gymnotus carapo also have JAR to reduce the probability of coincidence of pulses. We analyze this response signal and design the phase difference algorithm. We expect that simple algorithm inspired by weakly electric fish can be used in many engineering fields.

• Journal of Yeungnam Medical Science
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• 제28권2호
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• pp.105-115
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• 2011

Mercury is a toxic, persistent pollutant that bioaccumulates and biomagnifies through food webs. People are exposed to methyhnercruy mainly through their diet, especially through the consumption of freshwater and marine fish and of other animals that consume fish (e.g., marine mammals). All humans are exposed to low levels of mercury. Dietary patterns can increase exposure to a fish-eating population where the fish and seafood are contaminated with mercury. The primary toxicity targets of mercury and mercury compounds are the nervous system, kidneys, and cardiovascular system. It is generally accepted that developing organ systems are most sensitive to the toxic effects of mercury. The fetal-brain mercury levels appear to be significantly higher than the maternal-blood mercury levels, and the developing central nervous system of the fetus is currently regarded as the main system of concern as it demonstrates the greatest sensitivity. The subpopulation that may be at greater risk for mercury toxicity are those exposed to higher levels of methylmercury due to carnivorous fish, including sharks.

• Journal of Nutrition and Health
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• 제5권3호
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• pp.127-133
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• 1972

This study was designed to observe the effect of ethanol extracts from fish flour on the nucleic acid metabolism in rats. Young rats, weighing 75-85g were used as the experimental animals and diet used were 8 kinds; diet supplemented with 10% fish flour, diets which were supplemented with the extracts and or remainders of fish flour after extracting by either 76% or 96% ethanol to the rice diet, respectively, and diet supplemented with 6% casein. After feeding corresponding diet for 40 days, RNA and DNA contents, and DNase activities in the liver, kidney and braid were determined. The results obtaioed from this study are summarized as follows: 1. The RNA contents of the ethanol-treatment groups are, in the liver and kidney, similar to, and in the brain, generally higher than, that of the control group. 2. The DNA contents of each organ show no difference between ethanol-treatment groups and control group, but in the liver, of ethanol extrat groups are lower than casein group. 3. the DNase activity of each organ in the ethanol-treatmeut groups, is generally lower than the control group. The above results indicate that ethanol extracts from fish flour have influence on the nucleic acid metabolism.

• Applied Microscopy
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• 제50권
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• pp.18.1-18.7
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• 2020

The olfactory anatomy and histology of Lethenteron reissneri were researched using a stereo microscope, a light microscope, and a scanning electron microscope. As in other lampreys, it shows same characters as follows: i) a single olfactory organ, ii) a single tubular nostril, iii) a single olfactory chamber with gourd-like form, iv) a nasal valve, v) a nasopharyngeal pouch, vi) a sensory epithelium (SE) of continuous distribution, vii) a supporting cells with numerous long cilia, viii) an accessory olfactory organ. However, the description of a pseudostratified columnar layer in the SE and Non SE is a first record, not reported in sea lamprey Petromyzon marinus. In particular, both 19 to 20 lamellae in number and olfactory receptor neuron's quarter ciliary length of the knob diameter differ from those of P. marinus. From these results, it might be considered that the olfactory organ of L. reissneri shows well adaptive structure of a primitive fish to slow flowing water with gravel, pebbles, and sand and a hiding habit into sand bottom at daytime. The lamellar number and neuron's ciliary length may be a meaningful taxonomic character for the class Petromyzonida.

• Environmental Analysis Health and Toxicology
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• 제16권4호
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• pp.197-204
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• 2001

Endocrine disruption in crucian carp (Carassius auratus) living in the branch of Han River were examined. Vitellogenin level in plasma was measured using ELISA system and aromatase mRNA level in brain was observed using RT-PCR technique. In all female fish, vitellogenin levels were in the range of 20∼40 $\mu\textrm{g}$/ml and aromatase mRNA expression could be detected on the agarose gel after RT-PCR. However, in case of males, vitellogenin level was elevated in only one fish, while vitellogenin was hardly detected in others. Aromatase was expressed in all males although the levels were relatively lower than the level in female fish. Testis-ova and any other histological changes of reproductive organ were not shown in both sexes.