• 한국양식학회지
• /
• 제8권2호
• /
• pp.117-131
• /
• 1995

현행의 해산어류 종묘생산 방법을 개량하여 보다 효율적인 종묘의 사육방법을 개발하고자, 감성돔과 황점볼락의 자어를 재료로 각각 여름과 겨울에 있어 순환여과식과 유수식 사육시스템에 의한 사육실험을 실시하고, 사육수의 수질환경 및 어체의 성장과 생존율을 비교하였다. 1 감성돔 순환여과식 사육시스템의 수온은 기온에 따라 변화하는 경향을 보였고, 유수식보다 평균 $1.4^{\circ}C$ 높은 $23.6\~26.4^{\circ}C$의 범위를 나타냈다 순환여과식 사육시스템에서의 비중은 $1.0252\~l.0266$의 범위로 비교적 안정되었으나, 유수식에서는 그 변화폭이 컷다. 사육수의 pH는 유수식 사육시스템에서 자연해수와 비슷한 변화를 보인 반면, 순환여과식에서는 7.51까지 낮아졌다. 사육수의 $NH_4-N,\;NO_2-N,\;NO_3-N$및 $PO_4-P$의 양은 순환여과식에서 애우 높았고, $NO_2-N$과 $NO_3-N$은 각각 3.623 ppm, 7.207 ppm까지 상승하였다. 순환여과식과 유수식 사육시스템간에 있어 어체의 전장, 체고 및 체중의 성장에는 유의한 차이를 인정할 수 없었다. 두 시스템의 어체 생존을은 F4 $71.2\%,\;F8\;66.2\%,\;R4\;16.2\%$, 그리고 R8 $5.5\%$의 순으로, 순환여과식 사육시스템에서 높았다. 2. 황점볼락 순환여과식 사육시스템에서의 수온은 유수식보다 평균 $1.5^{\circ}C$ 높은 $9.8\~14.6^{\circ}C$의 범위였다. 비중은 두 시스템에서 $1.0253\~l.0270$의 범위로 안정되었으나, 순환여과식 사육시스템에서 약간 높은 분포를 보였다. pH는 두 시스템에서 자연해수에 가까운 $7.96\~8.64$ 범위로 유지되었으나, 순환여과식 사육시스템에서 다소 낮아지는 경향이었다. 순환여과식에서의 $NO_2-N$과 $NO_3-N$ 양은 각각 0.433ppm, 2.333 ppm까지 높아져 유수식에 비해 높은 편이었으나, $NH_4-N$ 양은 오히려 낮았다. 순환여과식 사육시스템에서 어체의 전장 및 체중의 성장은 유수식에 비해 유의하게 빨랐으나, 체고의 성장에는 유의차가 없었다. 두 시스템의 어체 생존율은 $F4\;67.6\%$ 및 $R4\;73.6\%$로 나타나, 서로 비슷하였다.

• 한국어류학회지
• /
• 제19권2호
• /
• pp.154-159
• /
• 2007

수온 내성에서 적정 수온과 고수온 노출시의 변화를 살펴본 결과, 적정 수온에서 황점볼락 치어 사육 시 수온에 따른 성장 시험은 사육수온 $16^{\circ}C$에서 성장이 좋게 나타났으며(P<0.05), 고수온 노출 실험에서 먹이섭취반응은 $28^{\circ}C$ 실험구에서 먹이섭취반응이 미약하였으나, $27^{\circ}C$ 이하의 실험구에서는 비교적 활발한 경향을 보여 주었다. 밀도별 실험에서 성장은 실험개시 후 30일째부터 성장 차이를 보이기 시작하여, 실험종료 시에는 L당 1마리 수용한 실험구가 가장 성장이 빨랐으며, 반면 가장 고밀도인 250마리 실험구가 성장이 가장 늦게 나타났다(P<0.05). 생존율은 사육밀도가 높아짐에 따라 낮아지는 경향을 보였다. 사료 공급 횟수는 1일 2회 (10:00, 19:00) 사료를 공급한 실험구에서 가장 좋은 성장을 보였고(P<0.05), 생존율도 다른 실험구보다 좋은 72.5%의 결과를 보여주었다.

• 한국수산과학회지
• /
• 제10권4호
• /
• pp.259-265
• /
• 1977

굴 양식장의 환경연구중 거제만양식장의 밀도 및 노화정도에 관한 기초조사를 1977년 6월부터 11월까지 6개월간에 걸쳐 실시하였다. 1. 거제만해역의 면적은 $48.87km^2$이고 도수산국에 등록된 이 해역내의 양식장 수면적은 $10.91km^2$이다. 해역면적에 대한 면허면적은 $22.23\%$이고 면허면적과 해역면적의 비는 1 : 4.48이다. 2. 부영양화의 정도를 A,B,C로 구분하여 C단계를 과영양화로의 과도기단계라 할때, 거제만은 양식어장으로서 수질은 A단계로 양호한 편인데 비해 저질은 C단계로 부영양화의 한계치에 도달되었거나 또는 약간 상회하며 과영영화로 진입하고 있다.

• 한국축산시설환경학회지
• /
• 제1권1호
• /
• pp.65-75
• /
• 1995

This experiment was carried out to the effects of population density and C/N ratios of feed on the growth, reproductive effciency and cast producation of the earthworm(Eisenia foetida). The population densities of 50, 100, 150, 200 and 250 individuals of the earthworm fed with different C/N ratios of 25, 35, 45 and 55 cow manures were studied in rearing box($6,400cm^3$), and at the fertility stage during a period of 60 days. The results were summarized as follows; The survial rate(SR), increasing rate(IR), reproductive efficiency(RE) and cast production of the earthworms showed highest values in C/N ratio of 25. These results may indicate that C/N ratio of 25 is a very favourable feed for the growth of the earthworms. The survial rate(SR) indicated significant positive correlation with reproductive efficiency(RE) in different C/N ratios of feeds. The survial rate(SR) showed highest values in population densities of $50{\sim}100$ worms/$6,400cm^3(64.0{\sim}128.0cm^3/worm$). On the contrary, increasing rate(IR) tended to decreased with the increased population densities. The survival rate(SR) indicated significant negative correlation with reproductive efficiency(RE) in different population densities of the earthworms. The cast production estimated were $31.6mg{\sim}67.4mg/day/worm$ grown in optimum population densities($50{\sim}100\;worms/6,400cm^3$). The earthworm casting are an excellent soil conditioning material or organic fertilizer sources with a high chemical composition and their physical properties.

• Fisheries and Aquatic Sciences
• /
• 제19권4호
• /
• pp.15.1-15.5
• /
• 2016

Apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, nitrogen-free extract, and energy in selected carbohydrate sources including wheat flour (WF), ${\alpha}-potato$ starch (PS), ${\alpha}-corn$ starch (CS), Na alginate (AL), dextrin (DEX), and carboxymethyl cellulose (CMC) were determined for olive flounder. The olive flounder averaging $150{\pm}8.0g$ were held in 300-L tanks at a density of 30 fish per tank. Chromic oxide was used as the inert marker. Feces were collected from the flounder by a fecal collector attached to a fish rearing tank. Apparent dry matter and energy digestibilities of flounder fed WF, PS, CS, and DEX diets were significantly higher than those of fish fed AL and CMC diets. Apparent crude protein digestibility coefficients of flounder fed PS and CS diets were significantly higher than those of fish fed AL, DEX, and CMC diets. Apparent crude lipid and nitrogen-free extract digestibility coefficients of flounder fed PS and DEX diets were significantly higher than those of fish fed WF, CS, AL, and CMC diets. The present findings indicate that PS and DEX could be effectively used as dietary carbohydrate energy compared to WF, CS, AL, and CMC for olive flounder.

• 한국농공학회지
• /
• 제35권3호
• /
• pp.63-73
• /
• 1993

For a systematic approach to rural settlement planning, socio-economic and land use potentialities were analysed in 10 villages("Ri", the lowest-order administrative unit in Korea)of Izuk-myun, Anseong-gun, Kyeonggi province, the model area in this study. Socio-economic potentialities, sub-grouped into rural and urban related ones, were analysed by the principal component analysis technique, while land use potentialities by the land suitability system of which the physical analysis is based on geographical information system. The principal component of rurality is strongly related with 5 key variables such as annual increasing rate of farm households, ratio of over 1ha-households, ratio of full-time farmers, ratio of animal rearing households and the principal component of urbanity with 6 key ones such as population density, number of schools, number of shops and servicing facilities, number of daily bus routes, number of non-farm households, percentage of area of housing sites. The analysis procedure of land suitability using the geographical information system were generalized and the results of analysis on village sites and paddy and upland fields were presented. The whole land use planning was presented by the criteria of the land suitability rank and the priority order of land use. land use.

• 한국양식학회지
• /
• 제21권2호
• /
• pp.89-95
• /
• 2008

Flounder were fed a reference diet and test diets containing various feed ingredients: mackerel fish meal, meat meal, soybean meal, wheat flour, wheat gluten, corn gluten meal and brewer's yeast. Apparent digestibility was determined using a reference diet with 0.5% chromic oxide indicator and test diets contained 70% reference diet and 30% of the feed ingredient being evaluated. Apparent digestibility coefficients for amino acid and energy in the reference and test diets were determined, and digestibility coefficients for the test ingredients were calculated based on differences in the digestibility of test diets relative to the reference diet. The fish averaging 300 g were held in 2000 L tanks at a density of 20 fish per tank. Feces were collected from three replicate groups of fish using a fecal collection column attached to fish rearing tank. Apparent total amino acids digestibilities(90-95%) of mackerel fish meal, soybean meal, wheat gluten, corn gluten meal and brewer's yeast were higher than those of meat meal and wheat flour(P<0.05). Apparent energy digestibilities(86-98%) of mackerel fish meal, meat meal, soybean meal, wheat gluten and corn gluten meal were significantly higher(P<0.05) than those of wheat flour and brewer's yeast. These results provide useful information about nutrient and energy utilization for flounder.

• 한국양식학회지
• /
• 제21권3호
• /
• pp.167-171
• /
• 2008

원생동물 섬모충의 한 종인 Euplotes는 해산어 종묘생산시설의 로티퍼 대량배양수조에서 혼재생물로서 매우 자주 관찰된다. 그들은 로티퍼에게 먹이로 첨가되는 농축 상태의 먹이(미세조류)를 중간에서 가로채어 빠른 속도로 증식하면서 로티퍼의 증식을 방해한다. 더불어 이때 형성된 배양수조내의 세균상은 로티퍼의 전멸을 초래하기도 한다.

• 수산해양교육연구
• /
• 제28권4호
• /
• pp.1098-1106
• /
• 2016

To study the influence of light intensity on blind-side hypermelanosis of starry flounder, Platichthys stellatus, we compared growth, glucose, cortisol, ratio of malpigmented blind-side area, ambicolored fish ratio and expression of mch mRNA for 60 days in 0 lux(darkness) and 20 lux(low light density). The test was done in duplicate at 50 fish/tank with the selected ordinary juvenile flounder. The rearing was performed in FRP aquarium tanks ($H100cm{\times}L100cm{\times}W100cm$). Growth was higher in the 0 lux. The ratio of malpigmented blind-side area and ambicolored fish ratio were significantly higher at the 0 lux than at the 20 lux. The result suggests that 20 lux could inhibit the hypermelanosis. The expression level of MCH 1, 2 mRNA was significantly lower in 0 lux, indicating that MCH 1, 2 and light intensity are related to blind-side hypermelanosis of starry flounder.

• Fisheries and Aquatic Sciences
• /
• 제26권10호
• /
• pp.583-592
• /
• 2023

Celebes rainbow (Marosantherina ladigesi) is one of Indonesia's exported ornamental fish commodities, but the exploitation of this fish only relies on wild catches. The rise of unlimited fishing, especially those using poison, has changed the aquatic environment, threatening sustainability and causing fish extinction. This study aimed to evaluate the effectiveness of several types of feed in improving the absolute growth rate (AGR), specific growth rate (SGR), survival rate (SR), feed conversion ratio (FCR), feed efficiency (FE), hematology, and immune response of Celebes rainbow. The fish used in this study were male ornamental Celebes rainbow (M. ladigesi) weighing 1.32 ± 0.21 g/ind, reared in 54 L-aquariums at a stocking density of 30 individuals/aquarium for six weeks. The fish were fed according to the test diet consisting of live Tubifex sp worms, dry Tubifex sp worms, Spirulina platensis, and crumble pellets. The parameters observed were AGR, SGR, SR, FCR, FE, hematology, intestinal histology, liver histology, and a challenge test with the pathogenic bacteria Aeromonas hydrophila. The results showed that fish-fed live Tubifex sp worms had better AGR, SGR, SR, FCR, FE, hematology, and disease resistance compared to all other treatments. These results indicate that live Tubifex sp worms are the best feed for rearing Celebes rainbow.