• 한국양식학회지
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• 제22권1호
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• pp.1-4
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• 2009

본 연구는 사료급이율이 여름철에 사육된 넙치 성어의 성장 및 체조성에 미치는 영향을 조사하고자 수행되었다. 최초 평균체중 535g의 실험어를 12개 수조(1.8톤)에 15마리씩 사료급이율 별 3반복으로 수용하여, 1일 2회 실험사료를 급이하며 10주간 사육하였다. 사료급이율은 만복(100%), 만복의 90%, 80%, 70%(어체중에 대한 일일 사료섭취율 기준)로 설정하였다. 사육기간 동안의 평균수온은 $19.2{\pm}2.8^{\circ}C$였다. 사육실험 후, 증체율, 일일사료섭취율 및 비만도는 사료급이율에 따라 유의한 차이를 보였으나, 생존률 및 사료효율은 모든 실험구간에 차이가 없었다. 증체율과 어체의 비만도는 일일 사료급이율이 증가함에 따라 증가하였으며, 만복의 90% 급이구는 만복 급이구와 유의한 차이가 없었으나, 80% 및 70% 급이구는 만복 급이구에 비하여 낮은 결과를 보였다. 실험 종료시, 실험어의 등근육과 간의 일반성분은 실험구간에 특별한 변화경향을 보이지 않았다. 본 연구의 증체율 및 비만도 결과로 볼 때, 여름철에 넙치 성어(535-928 g)의 적정 성장 및 비만도 유지를 위해서는 만복의 90%로 사료를 급이 하여도 좋을 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1111-1115
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• 1999

In order to determine the appropriate sampling time for blood metabolites of periparturient cows, the changes of the blood composition in relation to time of day were evaluated in sixteen multiparous Holstein cows at 1 wk prepartum, 1 and 6 d postpartum. Blood samples were collected at 08:30, 10:00, 15:30 and 17:00 h in each sampling day, and the sampling times at 08:30 and 15:30 h were prior to feeding. The rectal temperature of cows increased gradually from 08:30, to 17:00 h, but blood Hct and Hb decreased constantly. Plasma non-esterified fatty acid (NEFA) concentration at 08:30 h was two-fold higher than those at 10:00, 15:30 and 17:00 h from 1 wk prepartum to 6 d postpartum, and the value was maximum at 1 d postpartum. The highest plasma urea-N was observed at 10:00 h from 1 wk prepartum to 6 d postpartum. Plasma glucose and total protein were not affected by sampling time. The data indicated that blood samples of periparturient cows should be collected before morning feeding for the diagnosis of energy status, because plasma NEFA was the highest before morning feeding.

• Fisheries and Aquatic Sciences
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• 제17권4호
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• pp.441-448
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• 2014

We examined the effects of dietary nutrient content, feeding period, and feed allowance on compensatory growth, food use, chemical composition, and serum chemistry of juvenile olive flounder Paralichthys olivaceus. We placed 720 juvenile fish into 24 400-L flow-through round tanks (30 fish per tank).A $2{\time}2{\time}2$ factorial design (diet: control (C) and high protein and lipid (HPL) ${\time}$ feeding period: 8 and 6 weeks ${\time}$ feed allowance: 100% and 90% of satiation) was applied. Fish were hand-fed twice daily, based on the designated feeding schedule. Weight gain and food consumption were affected by both the feeding period and feed allowance, but not by diet. The food efficiency ratio was not affected by diet, feeding period, or feed allowance, but the protein efficiency ratio and protein retention were affected by diet and feeding period, respectively. We found that the full compensatory growth of fish was not achieved at a restricted feeding allowance.

• Ocean and Polar Research
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• 제32권2호
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• pp.165-175
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• 2010

Dietary lipid biomarkers (fatty acids, fatty alcohols, and sterols) in adult specimens were analyzed to compare and understand the feeding ecology of the euphausiid, Euphausia pacifica, from three geographically and environmentally diverse Korean waters (Yellow Sea, East China Sea, and East Sea). Total lipid content of E. pacifica from Korean waters was about 10% dry weight (DW) with a dominance of phospholipids (>46.9% of total lipid content), which are known as membrane components. A saturated fatty acid, C16:0, a monounsaturated fatty acid, C18:1(n-9), and two polyunsaturated fatty acids, C20:5(n-3) and 22:6(n-3), were most abundant (>60% of total fatty acids) in the fatty acid composition. Some of the fatty acids showed slight differences among regions although no significant compositional changes of fatty acids were detected between these regions. Phytol, originating from the side chain of chlorophyll and indicative of active feeding on phytoplankton, was detected all samples. Trace amounts of various fatty alcohols were also detected in E. pacifica. Specifically, krill from the Yellow Sea showed relatively high amounts of longchain monounsaturated fatty alcohols (i.e. 20:1 and 22:1), generally found in herbivorous copepods. Three different kinds of sterols were detected in E. pacifica. The most dominant of these sterols was cholest-5-en-$3{\beta}$-ol (cholesterol). The lipid compositions and ratios of fatty acid trophic markers are indicative of herbivory in E. pacifica from the Yellow Sea and East Sea (mainly feeding on dinoflagellates and diatoms, respectively). The lipid compositions and ratios of fatty acid trophic markers are indicative of carnivory or omnivory in E. pacifica from the East China Sea, mainly feeding on microzooplankton such as protozoa. In conclusion, lipid biomarkers provide useful information about krill feeding type. However, further analyses and experiments (i.e. gut content analysis, in situ grazing experiment, etc.) are needed to better understand the feeding ecology of E. pacifica in various marine environments.

• Asian-Australasian Journal of Animal Sciences
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• 제7권4호
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• pp.555-561
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• 1994

This paper presents results from a study of the body composition and sensory characteristics of female weaner goat meat. A completely randomized $3{\times}3{\times}2$ factorial design was used. Factors were genotype (Thai native; TN, 75% TN $\times$ 25% Anglo-Nubian; AN and 50% TN $\times$ 50% AN), feeding {grazing only, low (1.0% BW/d) and high (1.5% BW/d) concentrate supplementation and parasite control (undrenched and drenched)}. It was shown that there was no effect of genotype on body components and dressing percentage. However, TN and 75% TN $\times$ 25% AN kids had significantly (p<0.05) higher muscle to bone ratios (4.20% and 4.20%, respectively) compared with 50% TN $\times$ 50% AN kids (3.88%). Kids on grazing only had significantly (p<0.01) higher muscle percentage (64.12%) than did kids in low (61.30%) and high (60.62%) supplementary feeding program, but there was no significant (p>0.05) difference between low and high supplementary feeding groups. Kids offered supplementary feeding had significantly (p<0.01) higher percentages of total fat, intermuscular fat, pelvic fat and kidney fat than those of grazing only. Kids offered supplementary feeding had significantly (p<0.05) higher muscle to bone ratios and significantly (p<0.01) higher muscle plus fat to bone ratios compared with those of grazing only. This may be due to significantly lower (p<0.01) bone contents (14.95, 14.17 and 16.8% for kids offered low and high supplementary feeding and grazing only, respectively. There was no significant difference in sensory characteristics of goat meat between genotypes or feeding groups.

• 한국수산과학회지
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• 제54권1호
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• pp.64-72
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• 2021

The feeding habits of the Japanese jack mackerel Trachurus japonicus were studied in the Southern Sea of the Republic of Korea. To assess the effects of season, sampling was conducted in February (winter), May (spring), and August (summer), 2020. The total length of each fish was measured in 1 cm intervals. Diet composition showed the highest species diversity during winter. Diet composition changed from copepods to euphausiids as the total length of jack mackerel increased, except during winter. The most important seasonal prey were copepods in winter and summer and euphausiids in spring. Species diversity of the zooplankton community structure was highest in winter. Among the zooplankton communities, copepods were dominant in all seasons. Species with a high electivity index in all seasons were relatively large zooplankton of ≥2 mm. Jack mackerel had ontogenetic diet change, exhibited diet selectivity depending on size, and its feeding habits were affected by the zooplankton community structure.

• 한국수산과학회지
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• 제46권6호
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• pp.753-760
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• 2013

Two feeding trials were conducted to investigate the effects of feeding rate and frequency on growth performance and body composition of juvenile Korean rockfish Sebastes schlegeli reared at $15.0{\pm}0.3^{\circ}C$. In the first trial, three replicate fish groups averaging $2.07{\pm}0.03g$ were fed a commercial diet with one of seven different daily feeding rates: 1.00%, 2.00%, 2.50%, 2.75%, 3.00%, 3.25%, and satiation (3.34%) based on body weight (BW). After four weeks of feeding, fish fed the 3% diet showed significantly higher weight gain (WG) and feed efficiency (FE) than fish that received the other feeding rates. In the second trial, the optimum feeding frequency was evaluated with three replicate fish groups averaging $2.04{\pm}0.03g$. Fish were fed a commercial diet at 2.87% BW with six different daily feeding frequencies: 2, 3, 4, 5, 7, or 9 meals. After four weeks of feeding, WG, specific growth rate, FE, and protein efficiency rate in fish fed 3 meals $d^{-1}$ were significantly higher than those of fish fed 7 or 9 meals $d^{-1}$. In both feeding trials, proximate composition of the entire body changed depending on the feeding rate or frequency. A broken-line regression analysis based on weight gain suggested that the optimum daily feeding rate and frequency for juvenile Korean rockfish at $15^{\circ}C$ was 2.9% BW $d^{-1}$ and 2-3 meals $d^{-1}$, respectively.

• 생명과학회지
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• 제21권4호
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• pp.568-575
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• 2011

본 연구에서는 제주도에서 자라는 인진쑥을 일정량 첨가한 TMR 사료를 개발하여, 이를 제주 한우에게 급여한 경우, 인진쑥의 급여가 한우등심의 성분조성에 미치는 영향을 확인하였으며, 그 결과로 고급화된 기능성 한우의 생산 가능성을 검토하였다. 대조군(control)은 인진쑥을 혼합하지 않은 비육우 사료를 급여하였고, 급여군(treatment)은 인진쑥을 혼합한 비육우 사료를 급여하였다. 한우등심의 수분, 조단백질, 조지방, 조회분 함량, 열량, 콜레스테롤 및 콜라겐은 인진쑥 급여에 의한 영향이 없었다. 무기질 함량은 대조군 및 급여군 사이에 유의한 차이가 없었으며, 총무기질 함량은 대조군 및 급여군이 각각 3,559.20 및 3,998.01 ppm으로 유의한 차이가 없었다. 비타민 $B_1$ 및 $B_2$함량은 대조군 및 급여군 사이에 유의한 차이가 없었다. 구성아미노산 총량은 대조군 및 급여군이 각각 14.56% 및 13.90%로 유의한 차이가 없었으며, 유리아미노산 총량은 대조군(763.06 ppm)과 급여군(720.92 ppm) 사이에 유의한 차이가 없었다. 포화지방산은 대조군 및 급여군이 각각 42.956% 및 40.918%이고, 불포화지방산은 각각 57.043% 및 59.083%이었다. 인진쑥을 급여한 한우등심에서 유의하게 증가한 지방산은 myristic acid, myristoleic acid, pentadecenoic acid, palmitic acid 및 ${\gamma}$-linolenic acid이었으며, 급여하지 않은 한우등심에서 많이 함유된 지방산은 arachidic acid이었다(p<0.05).

• 한국양식학회지
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• 제9권4호
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• pp.385-394
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• 1996

배합사료의 적정 급여 횟수를 조사하기 위해 사료조성이 다른 두 종류의 사료, 즉 어분이 $58\%$ 함유된 대조사료(D-1)와 어분을 육분, 콘글루텐밀, 대두박 및 혈분으로 $30\%$ 대체한 실험사료 (D-2)를 설계하고 d교 pellet 형태로 제조하여 각각 사료급여 횟수를 달리하여 사육실험하였다. 사료급여 횟수는 1일 2회(09 : 30, 16 : 00), 1일 오전 1회(09 : 30), 1일 오후 1회(16 : 00) 및 2일 1회(09 : 30)로 구분하였고, 절식 실험구도 설정하였다. 평균체중 25 g의 조피볼락 치어를 사료별, 사료급여 횟수별로 각각 2반복으로 배치된 실험수조(100 ${\ell}$ FRP)에 30마리씩 수용하여 15주간 사육실험한 결과, 성장율, 사료효율, 단백질효율, 어체성분 및 경제적인 면을 고려하여 1일 1회 또는 2일 1회 사료를 급여하는 것이 좋을 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제6권4호
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• pp.619-622
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• 1993

Rumen bacterial amino acids in sheep on urea diet were monitored to assess a possible change in amino acid synthesis as a long term response to high rumen ammonia environment. A sheep was fed a semipurified diet with soybean meal, followed by a diet with urea as a main nitrogen source. Mixed rumen bacteria were harvested from ruminal fluid taken 3 h after feeding (twice in soybean meal feeding and 6 times in urea feeding) and fractionated as cell wall, proteins and protein-free cell supernatant of monitor amino acids in each fraction. Ruminal ammonia concentration at the sampling ranged from 5.7 to 39.5 mgN/dl. Cell wall and protein fractions of mixed rumen bacteria were stable in their amino acid composition regardless of nitrogen sources of diet and the feeding duration. However, protein-free cell supernatant fraction showed a higher alanine proportion with urea feeding (18.6 and 28.2 molar % of alanine for samples from sheep fed soybean meal and urea, respectively) and its duration (20.6 and 32.9 molar % for samples from sheep on urea diet for 1 and 65 days, respectively). Total free amino acid level of bacteria was depressed in the initial period of urea feeding but restored on 65th day of the feeding. These results suggest that an alanine synthesizing system may develop in rumen bacteria as urea feeding becomes longer.