• Korean Journal of Poultry Science
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• v.47 no.2
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• pp.61-68
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• 2020

This study was conducted to compare and analyze meat quality of Korean native duck (KND) meat relative to stocking density. The stocking densities under investigation were 4, 5, 6, 7, 8 and 9 birds/㎡. The experiment comprised six treatments and four replications, wherein the breast meat (pH, meat color, and physicochemical properties) and leg meat (fatty acid contents) of 8-week-old KNDs (2.8±0.2 kg) were used. pH of breast meat decreased linearly and quadratically (P<0.05) as stocking density increased. Ash content also decreased linearly (P<0.05) as stocking density increased; however, moisture, fat, and protein contents did not differ significantly among treatments. Furthermore, meat color and cooking loss (CL) increased linearly (P<0.05) as stocking density increased whereas neither shear force (SF) nor water holding capacity (WHC) displayed a significant difference among treatments. Palmitic acid (C16:0) and stearic acid (C18:0) contents decreased quadratically (P<0.05) as stocking density increased whereas, conversely, linoleic acid (C18:1n9) and eicosenoic acid (C20:1n9) contents increased linearly (P<0.05) as stocking density increased. Additionally, γ-linoleic acid (C18:3n6) content increased linearly and quadratically (P<0.05) as stocking density increased, but a decrease (P<0.05) was observed in arachidonic acid (C20:4n6) content. Saturated fatty acid (SFA) and total unsaturated fatty acid (TUFA) contents did not show significant differences among treatments relative to stocking density. However, monounsaturated fatty acid (MUFA) content increased linearly (P<0.05) and polyunsaturated fatty acid (PUFA) content decreased linearly (P<0.05) as stocking density increased. These results can be utilized as basic data for research on the effect of stocking density on KNDs.

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.1-6
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• 2012

We studied that the effect of stocking density on growth and survival rate of the scallop, Chlamys farreri (initial shell height 32.97 mm and total weight 5.63 g) from June 2002 to October 2003 in the west coast of Korea. C. farreri is usually the west coast of Korea and northern China in the natural habitat of the coastal species. Range of surface water temperature in the study area was $4.3^{\circ}C$ to $25.3^{\circ}C$, salinity 29.2 psu to 32.1 psu, dissolved oxygen 5.32 mg/L to 7.51 mg/L and pH was 7.84 to 8.12, respectively. The stocking densities were 20, 30, 40 and 50 individuals per a compartment of suspension cage in culture beginning. After 16 months from initiation, ranges of shell height and mean total weight were from 64.35 mm to 76.23 mm and from 41.53 g to 64.85 g. The survival rate was from 82% to 100%. The growth rate of the scallop was negatively correlated with the stocking density. The growth of the shell height and total weight were decreased with decreasing of water temperature. Most of mortality of scallop occurred during March to April and September to October. Survival rate in the stocking density was decreased by density increase and was highest in 20 individual a compartment.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.41-47
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• 2013

This work was carried out to investigate performance and carcass yield of large-type broiler females at different stocking densities. Chicks (n = 492; 1-day-old; female; Arbor Acre broiler) were reared for six weeks (starter, 0~1 wk; earlier, 1~3 wk; finisher, 3~6 wk) and randomly divided into 3 treatments (4 replications/treatment, 36, 41 or 46 birds/replication). Treatments were T1 (10.9 birds/$m^2$), T2 (12.4 birds/$m^2$) and T3 (13.9 birds/$m^2$) by the stocking densities. Research indexes were livability, body weight, body weight gain, feed intake, feed conversion ratio, production efficiency factor, carcass yield and primal cuts ratio (wing, leg, back, breast and neck). Livability (%) was 90% or more for all treatments, but there was no significant difference on weekly livability (%). Body weight of T3 treatment were the lowest at 3 wk and body weight gain, feed intake, and feed conversion ratio were the lowest at 2~3 wk (P<0.05). Production efficiency factors of T1, T2 and T3 were 331.0, 340.8 and 336.0, respectively, and there was no significant difference among treatments. Leg meat ratio of T2 treatment was higher compared to other treatments at the age of 4 wk (P<0.05). Carcass yield of T1 treatment was the highest as 76.2% at the age of 5 wk (P<0.05). However, there was no significant difference on carcass ratio and partial meat ratio among treatments at the age of 6 wk. This result may provide the standard data of different stocking densities for heavy female broilers.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.927-936
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• 2022

The effects of seasonal differences and crating densities on the preslaughter losses, breast meat quality, and physiological indices of broilers were determined. A total of 600 broilers aged 35 days were divided into 10 treatment groups based on five crating densities (10.3, 11.5, 12.8, 14.1, 15.4 birds·m^-2) with two seasons (i.e., summer and winter) to give six replicates and were placed at various locations in the truck. The birds were transported in crates having dimensions of 1.0 m × 0.78 m × 0.26 m. The transportation distance was 20 km for 40 minutes (average 30 - 50 km·h^-1) during the early morning. The results revealed that broilers transported at densities of 14.1 and 15.4 birds·m^-2 recorded lower (p < 0.05) pH, water-holding capacity (WHC), and muscle redness compared to those at densities of 11.5 birds·m^-2. Furthermore, higher (p < 0.05) cooking loss was found in birds stocked at more than 14.1 birds·m^-2 compared to the other treatments. However, no effect (p > 0.05) with different crating densities on body weight loss, carcass traits, glucose, lactate, or muscle yellowness was observed. Crating density of 14.1 birds·m^-2 showed lower (p < 0.05) cortisol contents compared with birds at 10.3 and 15.4 birds·m^-2. Winter transportation had higher (p < 0.05) relative breast meat weight, cooking loss, muscle redness, and cortisol contents whereas summer transportation had higher (p < 0.05) glucose and lactate contents in the blood plasma of broilers. In conclusion, the stocking of 12.8 birds·m^-2 is recommended to minimize stress responses and undesirable changes that could negatively affect muscle quality.

• Korean Journal of Poultry Science
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• v.47 no.1
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• pp.1-7
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• 2020

The effect of stocking density on the growth and meat quality of native Korean chickens was investigated. A total of 364 one-day-old native Korean chickens were randomly assigned to one of 5 treatments, each of which was replicated 4 times. Five distinct stocking densities-14, 15, 16, 18, and 22 birds/㎡-were compared. The diet was fed ad libitum for 10 weeks. Results indicated that the final body weight, body weight gain, and feed intake were lower (P<0.05) for the 22 birds/㎡ stock density as compared to the other stock densities. There was no significant difference in the feed conversion ratio, proximate analysis (DM, crude protein, crude fat, and crude ash), water-holding capacity, and cooking loss among the different stock densities. These results indicate that increasing the stock density to 22 birds/㎡ elicits some negative effects on the growth performance and meat quality of Korean-native chickens.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.4
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• pp.407-412
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• 2013

We performed four sets of feeding trials to establish optimum feed size (Exp-I), stocking density (Exp-II) and feeding frequency (Exp-III and IV) for Korean rockfish. In Exp-I, three different particle sizes of a commercial diet (small, 2.0-2.1 mm; medium, 2.4-3.2 mm; and large, 4.0-5.3 mm) were fed to four replicate groups of fish ($22.8{\pm}0.1g$), each of which was fed to apparent satiation for six weeks. In Exp-II, fish ($44.3{\pm}0.4g$) were reared at four stocking densities (1.5, 3.0, 4.5 and 6.0 $kg/m^3$) and fed a commercial diet to apparent satiation for four weeks. In Exp-III, fish ($14.8{\pm}0.1g$) were fed a commercial diet once, twice, thrice, $4{\times}$ or $5{\times}$ a day at a feeding ratio of 3.25% of body mass. Another group of fish was fed the same commercial diet $5{\times}$ a day to apparent satiation; this treatment was designated FS (five times satiation/day). In Exp-IV, fish ($31.3{\pm}0.1g$) were fed a commercial diet once, twice, thrice or $4{\times}$ a day to apparent satiation. Another group of fish was fed to apparent satiation once every 48 hours. In Exp-I, fish fed the large particle (4.0-5.3 mm) diet had a significantly higher feed conversion ratio and lower protein efficiency ratio than fish fed the small particle diet. In Exp-II, groups of fish reared at densities of 4.5 and 6.0 $kg/m^3$ had significantly higher feed intake and growth performance than fish reared at 1.5 and 3.0 $kg/m^3$. In Exp-III, fish fed to apparent satiation had significantly higher growth performances than fish fed once or $4{\times}$ a day. A significantly higher feed conversion ratio and a lower protein efficiency ratio were obtained in the FS group. In Exp-IV, growth performance and feed utilization efficiency were not significantly affected by experimental variation in feeding frequency. Fish fed to apparent satiation once every 48 hours had better feed utilization than those in other treatments and growth performances of those were comparable. Therefore, the optimum feed particle size, stocking density and feeding frequency for Korean rockfish under conditions we used were 2.0-3.2 mm, 4.5-6.0 $kg/m^3$, and once a day or once every 48 hour, respectively.

• The Korean Journal of Malacology
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• v.31 no.2
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• pp.93-101
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• 2015

The effects of different stocking densities on the growth and survival rate of the 3-year-old pacific abalone, Haliotis dicus hannai were investigated in marine net cage for a year. Stocking densities in net cage ($2.4{\times}1.2m$) was set 15, 30, 45 and 60 percentage (= per)/sq m (square meter, $m^2$) with share to cross-sectional area per shelter. The water temperature during the testing period was $8.2^{\circ}C-22.1^{\circ}C$, and salinity is $33.5{\pm}0.6psu$, and dissolved oxygen is $7.87{\pm}0.86mg/L$. In the shell length (initial size : $71.50{\pm}2.28mm$) growth and shell breadth (initial size : $46.43{\pm}2.28mm$) of the test abalones, the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rates (SGR) of the 15 per/sq m and 30 per/sq m were higher than those of 45 per/sq m and 60 per/sq m density group (P < 0.05). Also in the weight (initial weight : $35.7{\pm}8.1g$), it showed the same results. In survival rates, it were that 15 per/sq m and 30 per/sq m is significantly higher than 45 per/sq m and 60 per/sq m. Therefore, it was that the 15 per/sq m is optimized stocking density in marine net cages about the 3-year-old pacific abalone over 70 mm size. The result shown that total cross-sectional area under the shelter is based on 15 per/sq m ($2.4{\times}2.4m$, 354 number in a net cage) is suitable for fast growth and survival. But if the economy consider, optimized stocking density would be appropriate to accept 30 per/sq m ($2.4{\times}2.4m$, 710 number in a net cage).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.4
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• pp.359-365
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• 2011

This study was conducted to investigate the production, elver stocking, rearing facilities and rearing method of eel culture to determine aquaculture management conditions for optimal rearing of eel Anguilla japonica. The production of eel culture was evaluated by the proportion of eels from the main inland fin fish species production in Korea. Elver stocking was assessed by the elver stocking densities of pond and recirculation culture. Rearing facilities were investigated according to the rearing tank size proportion of the pond and recirculation culture. We selected sample farms by region and by size. We visited sample farms and recorded the number of elvers stock for pond area, size of tanks, feed and feed quantity, and the size and number of harvest eels. The production capacity of Jeollanam-do and Jeollabuk-do were 71.9% and 21.3% respectively. This production quantity represented 93.2% of the total Korean eel production quantity. In Jeollanam-do, there are 236 eel farms, 202 pond farms, and 34 recirculation aquaculture facilities. The elvers' first density data by each aquaculture method revealed that elvers' first density varied more in recirculation system farms, as compared to pond aquaculture. In intensive pond farms, the elvers' first density decreased as the size of farm increased. There was a correlation between the size of tank(x) and the facility of a water wheel for dissolved oxygen in pond culture systems(y=0.022x-0.494; $R^2$=0.860). Another strong correlation was found between the weight of eel(x) and eel density(y) in pond culture systems(y=283.5x-0.27; $R^2$=0.992). Finally, there was a strong correlation between the length of eel(x) and the weight of eel(y) in intensive pond culture(y=0.0005x-3.2783; $R^2$=0.9775). The final survival rate did not differ significantly among pond sizes and culture types.

• Journal of Aquaculture
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• v.13 no.4
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• pp.285-293
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• 2000

Mortality suffered by the sea squirt in indoor experiment was higher at the stocking density of 12 kg than that at 3 and 6 kg. Daily mortality was also higher at 8 t:: thermal fluctuation than that at 3 and 5$^{\circ}C$. The thermal fluctuation observed at the depth of 5 m during June was higher, i.e. 7.4$^{\circ}C$ but it was just 2-4$^{\circ}C$ during mid-May. It did not fluctuate at all during the period from January to February. Mortality was higher at the stocking density of 12 kg during June than at 10 and 15 m depth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.588-596
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• 2014

To examine the influences of water temperature and stocking density on feeding, growth and blind-side hypermelanosis of the starry flounder Platichthys stellatus, we performed an experiment with fry at two densities: 2 and 8 fish/L. The fry had a total length of $3.2{\pm}0.1cm$, body weight $0.6{\pm}0.1g$, and pigmented patches (pigmented ratio $2.6{\pm}0.4%$) on the blind side. Duplicate experiments were conducted in 93.7 L glass tanks for 120 days, from July to November. We determined daily food intake (DFI), food efficiency (FE), growth, survival rate, ratio of hypermelanic fish, and pigmented area rate on the blind side at 60-day intervals. The DFI was less than 50 mg/fish/day, and growth was delayed from July to September (water temperature [WT]> $20^{\circ}C$). After October, when WT < $20^{\circ}C$, the DFI increased significantly and the growth was accelerated, suggesting that the rearing temperature of starry flounder in artificial facilities should be < $20^{\circ}C$. While the FE, and survival did no differ between the two density groups, DFI and growth were significantly higher at 2 fish/L than at 8 fish/L. There was no difference in the pigmented area ratio between the two density groups. Although the hypermelanosis was not correlated with body size, the malpigmentation increased with growth. These results suggest that a high stocking density is not the main cause of blind-side hypermelanosis, although it can accelerate hypermelanosis in the starry flounder.