• 한국수산과학회지
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• 제21권2호
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• pp.80-84
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• 1988

방어, 참돔, 피조개, 굴 4종의 어패육에 V. vulnificus M-8을 접종하여 저장온도와 시간에 따른 균수의 변화를 시험한 결과는 다음과 같다. 1. V. vulnificus의 저온저항성은 $-20^{\circ}C$의 $1.5\%$ 식염-인산완충희석수에서는 32시간에 거의 사멸하였으며, 방어육 균질액에서는 인산완충희석수에서 보다 감소가 완만하였고 72시간 이후에도 균이 검출되었다. 그리고 $4^{\circ}C$ 저장에서도 균의 감소가 현저하였다. 따라서 이 균의 저온저항성은 약하지만 단시간 냉동 및 냉장에 의한 균의 사멸은 어렵다는 것을 알 수 있었다. 2. 어패육에 접종하여 $30^{\circ}C$에 저장한 시료중의 V. vulnificus의 증식은 일반적으로 16시간만에 최대균수에 달하였으나 피조개의 경우는 12시간으로 약간 빨랐으며 특히 방어육에 있어서는 초기에 감소하는 특징과 더불어 균의 증식속도가 완만하였다. 그리고 가열처리육보다 생육에서의 균의 증식이 빠르게 나타났다.

• Fisheries and Aquatic Sciences
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• 제14권2호
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• pp.105-110
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• 2011

This study determined the effects of the dietary moisture level and feeding rate on the growth and gastric evacuation of young olive flounder. Four experimental diets with different moisture levels (9%, 21%, 30%, and 40%) were prepared through the addition of water to the commercial extruded pellet. Three replicate groups of fish (initial weight: $106{\pm}1.4\;g$) were fed diets containing 9%, 21%, 30%, and 40% moisture to satiation or a moisture level of 9% and 30% at a restricted feeding rate (95% of satiation) for 15 weeks. The mean water temperature was $22{\pm}1.6^{\circ}C$ during the feeding trial. Gastric evacuation rates were determined post-feeding. The dietary moisture levels did not significantly affect weight gain, but the weight of the fish receiving 9% and 30% moisture diets to 95% satiation were significantly lower than those of the fish fed 9-40% moisture diets to 100% satiation (P<0.05). The feed efficiency, protein efficiency ratio, viscerosomatic index, and survival were not significantly affected by the dietary moisture levels and feeding rates. The daily feed intake of the fish fed to 100% satiation did not significantly differ among the treatment groups. The stomach contents that peaked within 3 h of feeding gradually decreased, and the stomachs of fish were completely evacuated within 18 h. The contents of the intestine peaked at 3-12 h post-feeding, and then declined with the intestine being mostly evacuated at 30 h. The moisture of the stomach contents reached approximately 70% within 3 h post-feeding and gradually increased to approximately 75% within 12 h. No considerable differences were observed in the gastric evacuation and moisture levels of the stomach contents in the fish fed the different diets. The results of this study suggest that the gastric evacuation of olive flounder was not affected by the dietary moisture level and that the addition of water into the diet displayed no beneficial effects on the growth of young olive flounder.

• 한국수산과학회지
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• 제47권5호
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• pp.577-581
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• 2014

The aim of this study was to investigate the effect of diet extruder conditions, such as feed-loading rate and screw speed, on growth performance and biochemical responses in olive flounder Paralichthys olivaceus. Over 8 wks, we used four identical diets (triplicated per treatment) with differing ratios of feed-loading rate (kg/h):screw speed (rpm/min) in a laboratory-scaled twin-screw extruder of 50:640, 80:640, 120:640, and 80:400, designated as EP1, EP2, EP3, and EP4, respectively. Screw speed impacted the buoyancy of experimental diets. Diets produced at a screw speed of 640 rpm/min floated for > 24 hrs, whereas those produced at a speed of 400 rpm/min sank between 10 s and 5 min. Fish that were fed EP1 and EP4 diets grew significantly faster than those fed EP2 and EP3 diets. Fish fed EP1 diets ate and gained weight most efficiently among treatments, a result that is likely to be related to feed-loading rate, i.e., ingredients extruded at a low feed-loading rate may have more time to cook in the pre-conditioner of the extruder. A cooked diet may be easier to digest in fish. Fish fed EP4 diets also showed significant weight gain, as compared to those fed EP2 and EP3 diets. However, we found no differences among treatments in proximate compositions of dorsal muscle, liver, and viscera of fish. Our results suggest that extruder conditions, may influence feed quality, impacting feed efficiency and growth of fish.

• Journal of Ecology and Environment
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• 제31권1호
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• pp.45-67
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• 2008

Ocean climate variables ($1900{\sim}2005$), time series of catches ($1910{\sim}2005$) and body size data were used to assess the year-to-year and decadal scale fluctuations in abundance of the fish populations (Japanese sardine, anchovy, jack mackerel, chub mackerel, Pacific saury and common squid) that have spawning grounds in the East China Sea and its adjacent regions. A negative correlation between the abundance of pelagic fishes (e.g. jack mackerel) in the Tsushima Warm Current (TWC) region and the Kuroshio-Oyashio Current (KOC) region was attributed to the climatic modulation of larval transport and recruitment, which depends on the winter monsoon-induced drift, current systems, and spawning season and site. The changes in abundance and alternation of dominant fish populations in the two regions in the 1930s, 1970s, and late 1980s mirrored changes in the climate indices (ALPI, AOI and MOI). Oscillations in the decadal climate shifts between the two regions led to zonal differences in larval transport and recruitment, and hence differences in the abundance of the pelagic fish populations. During deep Aleutian Lows, as in the 1980s, larval transport from the East China Sea to the KOC region increases in association with the strong winter Asian monsoon, cool regime and increased volume transport of the Kuroshio Current systems, whereas during a weak Aleutian Low (as in the 1990s), larval transport to the TWC region increased in association with a weak winter Asian monsoon, a warm regime, and increased volume transport of the Tsushima current system. We postulate that the increased chub mackerel abundance in the TWC region and the decreased abundance in the KOC region in the 1990s are partly attributed to changes in recruitment and availability to the fishing fleets under the warm regime in the spawning and nursery grounds in the East China Sea in association with the quasi-steady state of mild winter monsoon in the 1990s. The fluctuations in chub mackerel and jack mackerel abundance are under the environment-dependant growth form, although the tropicalization was identified in the TWC region. The density-dependant growth form was found in Japanese sardine populations, but no tropicalization by fishing was identified in the long ($10{\sim}15$ year) periods of abundance despite their short ($3{\sim}4$ year) generation time, suggesting that the environment-dependant growth form drove the changes in abundance. Year-to-year and decadal scale variations in abundance and population structure of the Pacific saury responded to climate regime shifts (1976/1977, 1988/1989), suggesting that the fish is a key bio-indicators for changes in the ecosystem.

• Asian-Australasian Journal of Animal Sciences
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• 제23권6호
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• pp.724-732
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• 2010

Two feeding experiments were conducted to investigate the effects of dietary paprika (DP) and lipid (DL) levels on growth performance and skin pigmentation of pale chub, Zacco platypus. Six diets (designated as $P_0L_8,\;P_0L_{17},\;P_8L_8,\;P_8L_{17},\;P_{16}L_8\;and\;P_{16}L_{17}$) were formulated to contain 0%, 8% and 16% paprika with 8% and 17% lipid, respectively. For the growth experiment (Exp I), three replicate groups of fish (average weight 2.6${\pm}$0.2 g) were fed one of the six experimental diets for 8 weeks. At the end of the feeding period, survival was above 94% and not significantly different among dietary treatments. Weight gain, feed efficiency and protein efficiency ratio of fish fed the $P_{16}L_8$ diet were lower than for fish fed the $P_0L_8$ diet. The highest total carotenoid (TC) content was observed in fish fed the $P_{16}L_8$ diet. For the pigmentation experiment (Exp II), each experimental diet was fed to two replicate groups of fish (average weight 9.0${\pm}$0.5 g) for 8 weeks. At the end of the feeding period, TC content of the skin was significantly affected by DP (p<0.05). The highest TC content of the skin was observed after 6 weeks of feeding at all dietary treatments. Astaxanthin content of the skin was not affected by DP and DL (p>0.05). The capxanthin and zeaxanthin contents of skin increased significantly with increasing DP, whereas the opposite trend was observed for lutein and ${\beta}$-cryptoxanthin contents. The skin lightness ($L^*$ values) significantly decreased whereas the values of $a^*$ and $b^*$ were significantly increased in fish fed the diets containing paprika (p<0.05). The present results suggest that feeding a diet containing 8% paprika and 8% lipid for 6 weeks could improve skin pigmentation of pale chub without any adverse effects on growth performance.

• 한국양식학회지
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• 제21권3호
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• pp.133-138
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• 2008

돌돔 Oplegnathus fasciatus과 넙치 Pralichthys olivaceus를 대상으로 사료 내 송이(Scoria)의 첨가에 따른 사육효과 및 단백질 소화율을 알아보기 위해 2가지 실험이 수행되었다. 돌돔(초기평균무게: 7.6 g)을 대상으로 한 1차 사양실험에서는 사료 내 송이함량을 0%(Con), 1%와 2%를 첨가하여 3반복으로 수행하였다. 9주간의 성장실험 결과, 송이 2%를 첨가한 실험구에서 대조구와 비교해 유의적인 차이가 없었으나 송이 1%를 첨가한 실험구에서 대조구와 비교해 유의적으로 낮은 값을 나타내었다. 단백질 소화율 측정 결과에서는 45.0%(Con), 60.6%(송이 1%), 64.0%(송이 2%)로 송이가 첨가된 실험구에서 대조구에 비해 유의적으로 높은 단백질 소화율을 나타내었다. 넙치를 대상으로 한 2차 실험은 1차 사양실험에서 확인되어진 증가된 단백질 소화율을 증명하기 위해 실시되었다. 실험사료는 송이 0%(Con), 1%, 2%, 3%, 4%로 조성되었다. 2차 실험의 단백질 소화율 결과에서는 사료 내 송이를 1%(56.7%), 2%(65.5%), 3%(52.8%) 첨가한 실험구에서 대조구(43.5%)에 비해 유의적으로 높은 값이 보였다. 반면 송이 4%를 첨가한 실험구에서는 단백질 소화율의 값이 41.4%로 대조구와 유의적인 차이를 보이지 않았다. 1 2차 사양실험의 결과를 종합하여 볼 때 해산어 배합사료 내 송이의 첨가는 사료 내 단백질 소화율을 증진시킬 수 있을 것으로 보여지며, 그 첨가함량은 $2{\sim}3%$ 내외가 될 것으로 판단된다.

• 한국양식학회지
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• 제6권2호
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• pp.89-105
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• 1993

n-3HUFA가 조피볼락의 성장, 영양소축적효율 및 체성분에 미치는 영향을 구명하기 위해 오징어 간유 및 대두유를 지질원으로 사료에 첨가하여 사료의 n-3HUFA 함량이 $0\~1.5\%$가 되도록 조정하여 사육한 결과는 다음과 같다. 성장, 사료효율 및 영양소 축적효율 모두 n-3HUFA 무첨가 사료에서 가장 낮은 값을 나타내었으며, 사료의 n-3HRFA 함량의 증가와 더불어 그 효과가 현저히 개선되다가 $1.2\%$ 이후에는 더이상 개선효과가 없었다. n-3HUFA함량이 높은 실험구의 간지질(비극성 지질) 함량은 감소한 경향을 보였으나 간의 glycogen 함량은 증가하였으며, HSI 값도 다소 증가하였다. 전어체의 지질함량 및 내장의 지질함량은 모두 사료의 n-3HUFA 함량이 높은 실험구에서 높게 나타났으며, 이러한 증가는 비극성 지질의 변화 경향과 일치하였다. 간 극성 지질 중의 지방산조성은 사료의 지방산조성에 따라 변화하여, 사료의 n-3HUFA가 증가함에 따라 n-3HUFA와 18:1은 증가하였고, 18:2n-6과 18:3n-3은 감소하였다.

• 한국양식학회지
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• 제1권2호
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• pp.109-119
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• 1988

주요 단백질원이 북양어분(White fish meal)인 뱀장어용 배합사료에 각종 무기물질중 Co per와 Manganese에 대한 첨가 적양을 검토하기 위한 뱀장어 사육실험을 실시하였다. Cu 첨가 사육실험 결과, 5 $\mu$g/g 첨가구가 성장 및 사료효율이 가장 좋았고, 다소 비만도가 높은 결과를 보였다. 한편 가장 높은 농도인 20 $\mu$g/g 실험구에서 Cu에 의한 약해는 나타나지 않았으며, 무첨가구는 첨가 실험구보다 간 중양이 다소 낮은 경향을 보였다. 그리고 근육 및 간에서의 Cu 함양, 골격에서의 Al 함양은 사육중 Cu 함양에 비례하여 증가하며, 간에서의 Zn 함양은 반비례하였다. Mn 첨가 사육실험 결과, 20$\mu$g/g 첨가구에서 가장 종은 성장을 나타내었으며, 40$\mu$g/g 첨가구에서 사료효율이 가장 좋았다. 근육, 간 그리고 골격의 Mn 함양 및 간의 Cu 함양은 Mn 첨가양에 비례하여 증가하였다. 이상의 결과를 볼 때 북양어분을 주 단백질원으로 하는 뱀장어용 배합사료에 Cu 및 Mn의 적정 첨가양은 각각 5$\mu$g/g과 30$\mu$g/g 정도가 적합하다고 사료된다.

• Fisheries and Aquatic Sciences
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• 제7권1호
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• pp.1-9
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• 2004

Sweet smelt (Plecoglossus altivelis) were fed four different diets supplemented with either perilla oil $(2.0\%)$ rich in 18:3n-3 (CP), and perilla oil and Enteromorpha compressa meal $(2.0\%)$ (CPA), soybean oil rich in 18:2n-6 (CO), or soybean oil and algal meal (CA) for 4 weeks. The growth performance, fatty acid composition of muscle, plasma lipid peroxidation and blood components of the sweet smelt were then determined. The specific growth rate and feed efficiency in the fish fed the CPA diet were the highest, while the other groups showed similar results. The fatty acid composition of muscle in sweet smelt reflected the dietary lipids; 18:3n-3 was higher in the fish fed the CP and CPA diets, and 18:2n-6 was higher in the fish fed the CO and CA diets. The other fatty acid profiles presented almost no differences with respect to the diet composition. The fish fed the CA, CP and CPA diets contained significantly lower levels of triglyceride, thiobarbituric acid-reactive substances and hydroxyl radical in their plasma than that fed the CO diet. Phagocytic activity was the highest in the fish fed the CPA diet and higher in those of the fish fed the CP and CA diets compared to the CO diet group. The results from this study suggest that a dietary supplement of $2.0\%$ perilla oil together with $2.0\%$ E. compressa meal may improve the growth and health of cultured sweet smelt.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.70-70
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• 2003

This study was conducted to determine the effects of the dietary microbial phytase (P) supplementation on growth performance and bioavailability of phosphorus in juvenile olive flounder, Paralichthys olivaceus and juvenile Korean rockfish, Sebastes schlegeli fed soybean meal-based diets. Nine experimental diets were formulated to be isonitrogenous and isocalolic to contain 50.0%crude protein (CP) and 16.7kJ, 48.6% crude protein (CP) and 16.0kJ available energy/g without the dietary phytase supplementation for olive flounder and Korean rockfish, respectively : 100% fish meal (FM); 70% FM ＋ 30% soybean meal (SM); 70% FM ＋ 30% SM ＋ Phytase(P) 1000U/kg diet; 70% FM ＋ 30% SM ＋ P 2000U/kg diet; 70% FM ＋ 30% SM with phytase-treated (Ptre) P 1000U/kg diet; 60% FM ＋ 40% SM; 60% FM ＋ 40% SM ＋ P 1000U/kg diet; 60% FM ＋ 40% SM ＋ P 2000U/kg diet; 60% PM ＋ 40% SM with Ptre P 1000U/kg diet. After two weeks of the conditioning period, triplicate groups of 25 fish initially averaging 6.15$\pm$0.04g, was randomly distributed into the aquarium for olive flounder, and 20 fish initially averaging 7.25$\pm$0.04g was randomly distributed into the aquarium for Korean rockfish. After 8 weeks feeding trials, there was no significant difference on weight gain fish fed between 100% FM and 70% FM＋30%SM with Ptre P 1000U in olive flounder and Korean rockfish. Apparent phosphorus digestibility fish fed phytase supplemental diets were significantly higher than those of fish fed phytase non-supplemental diets in olive flounder and Korean rockfish. Therefore, these results indicated that pre-treated soybean meal with phytase 1000U could replace fishmeal up to 30% for the maximum growth of juvenile olive flounder and Korean rockfish. Phytase supplementation could improve apparent digestibility of phosphorus in olive flounder and Korean rockfish fed soybean meal based diets.