• Journal of Aquaculture
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• v.9 no.3
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• pp.233-237
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• 1996

A growth study was conducted to investigate the effect of stocking density on performance of juvenile fat cod (Hexagrammos otakii Jordan et Starks.). Fish averaging 13 g were stocked into duplicate tanks ($250\;{\ell}$ each) at four different densities of 330 g/$100\;{\ell},\;660\;g/100\;{\ell},\;990\;g/\;100\;{\ell}$, and $1330\;g/100\;{\ell}$, and fed MP diet containing $50\%$ frozen horse mackerel and $50\%$ commercial binder meal for 2 months. Weight gain, feed efficiency, survival rate, and protein retention were decreased as density increased. Whereas these parameters were not significantly different (P>0.01) fish stocked at initial stocking densities of $330\;g/100\;{\ell},\;660\;/g/100\;{\ell}\;and\;990\;g/100\;{\ell}$. Moisture and lipid content of whole body were not affected by stocking densities (P>0.01). These results indicate that stocking density should be considered, and $1{\~}2$ kg fish/$100\;{\ell}$ final stocking density for juvenile fat cod could be used to decrease production cost for the indoor tank (culture) system.

• Journal of the Ergonomics Society of Korea
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• v.14 no.1
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• pp.37-57
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• 1995

The purpose of this study was to investigate the elastic effect of deformation and restriction in wearing a support type panty stocking (PS). The study investigated deformation rate in all surface area, deformation rate in local area, length deformation rate, changes in slip and feeling of restriction under the standard laboratory condition. Two healthy adult females in twenties wore four types of PS. The result were as follows : The deformation rate in all surface area was 117 .approx. 132% in wearing support type PS, 157% in wearing mono type PS, due to the intensities of restriction. The deformation rate in local area was in order, course > oblique > wale direction. The largest deformation rate was observed in hip girth. Between the deformation rates in all surface and local areas was a high correlation acknowledged, especially the course direction showed a high correlation. Support type PSs showed more deformation and changes of slip than wool and mono type PS. Especially, changes of slip at the knee appeared greatly. The responses of restriction evaluated from a paired comparison method were in order, JS 2 > KS 4 > KS 9 > KS 5 > KS 1 > KM 3.

• Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.23.1-23.7
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• 2016

The effects of daily feeding frequency (Exp I), water temperature (Exp II), and stocking density (Exp III) on the growth of river puffer, Takifugu obscurus, juvenile fish of 10 and 40 g in body weight were examined to develop effective techniques to produce river puffer in a non-exchange water system. In Exp I, fish were fed commercial floating feed with 45 % protein one to five times per day to apparent satiation each by hand daily for 8 weeks at $25^{\circ}C$. In both the 10- and 40-g size groups, the final body weight, daily feed consumption, and weight gain of fish fed one meal per day were significantly lower than those of fish fed five meals per day (P < 0.05). However, there were no significant differences in the final body weight, daily feed consumption, and weight gain among fish fed two, three, and five meals per day. Feed efficiency showed decreasing tendency with increasing size of fish. In Exp II, fish of 10 and 40 g in initial body weight were reared with the commercial feed at $15-30^{\circ}C$ for 8 weeks. The weight gain of fish increased with raising water temperature up to $25^{\circ}C$ and decreased drastically at $30^{\circ}C$ for both sizes. The Q10 of specific growth rate was decreased with raising water temperature from 5.04 (temperature interval, $15-20^{\circ}C$) to 0.66 ($25-30^{\circ}C$) for the 10-g fish and from 4.98 to 0.31 for the 40-g fish. In Exp III, the effect of stocking density on growth was examined with fish of 10 and 40 g in initial body weight. The final body weight for initial stocking densities of 4, 8, and $12kg/m^3$ was significantly higher than that of $20kg/m^3$ for the 10-g fish, and the final stocking density reached 10.1, 19.2, 28.7, and $39.9kg/m^3$, respectively. For the 40-g fish, the final body weight for initial stocking densities of 3 and $6kg/m^3$ was significantly higher than that of 9 and $15kg/m^3$ and the final stocking density reached 7.38, 13.5, 17.1, and $27.5kg/m^3$, respectively (P < 0.05). In both groups, weight gain tended to decrease with increasing stocking density; however, survival showed no significant difference.

• Journal of Aquaculture
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• v.15 no.3
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• pp.131-138
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• 2002

Fed on commercial flounder diet at 20, 23 and $26^{\circ}C$ in semiclosed culture system for 32 weeks, the juvenile red drum (1.2 g) showed linear increase in daily feeding rate (DFR), growth (g/fish) and specific growth rate (SGR) with increasing temperature. In the second experimental series, the young red drum (214 g), cultured at densities of 2.16, 4.24 and 6.40 kg/$m^3$ in flow-through tanks at water temperatures from 12.3 to $27.2^{\circ}C$ for 25 weeks, grew faster at the stocking density of 2.16 kg/$m^3$ than at the densities of 4.24 and 6.40 kg/$m^3$ the difference in growth observed at the stocking densities of 4.24 and 6.40 kg/$m^3$ was not significant. The DFR and SGR were also significantly higher for the density group of 2.16 kg/$m^3$. Briefly, growth of the red drum increased with increasing tested range of temperature and was also faster with decreasing stocking density. However, the total growth (g/tank) increased with increasing stocking density.

• Korean Journal of Poultry Science
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• v.36 no.1
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• pp.1-7
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• 2009

This study was performed to evaluate the effect of the level of stocking density of housing with or without window on chicken meat quality. The incidence of $1^+$ grade of whole chicken housed with window significantly influenced by stocking density. The incidence of $1^+$ grade chicken at high stocking density ($0.050\;m^2$/head), standard stocking density ($0.066\;m^2$/head), and low stocking density ($0.083\;m^2$/head) was 26, 52, and 66%, respectively. Breast muscle of chicken housed with window and with low stocking density showed higher incidence of $1^+$ grade than high stocking density. Also minor and severe PSE (pale, soft, extractive) incidence of chicken meat were showed 4% each, while the $1^+$ grade chicken was not appeared at low density. In chicken thigh, the incidence rate was not affected by stocking density. In chicken housed without window, the incidence of $1^+$ grade chicken in high, standard, and low stocking density was 18, 8, and 46%, respectively. Also, the incidence of $1^+$ grade chicken breast was 2.6 times higher than the chicken in low stocking density. However, incidence of $1^+$ grade thigh was not affected by the stocking density. These results suggest that high stocking density significantly reduced the incidence of $1^+$ grade chicken meat regardless of housing with or without window.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.4
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• pp.541-548
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• 2023

Behavior serves as an important indicator of the effects of environmental stressors on organisms. In this study, one-year-old abalone Haliotis discus hannai (15.1±0.8 mm) were used and each 0.34 m2 tank was stocked with 100, 150, 200, 250, and 300 juvenile abalone. After 328 days, we found that the low stocking density treatment showed significantly higher growth, whereas the high stocking density treatment showed significantly lower growth. In addition, abalone showed a lower rate of movement, distance moved, and velocity at higher stocking densities, but only velocity differed significantly. In contrast, In the Supplied the feed tanks significant difference between the moving distance and velocity. When the two groups of different sizes were mixed in tank, the rate of movement, distance moned, and velocity showed significant differences between differently-sized indivisuals. Our study indicates that breeding abalone at high densities has a negative effect on their growth and survival, which is thought to primarily be caused by spatial competition, and secondarily by differences in body size, ultimately affecting growth and productivity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.747-752
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• 2011

The parrotfish Oplegnathus fasciatus is a sub-tropical species that is difficult to culture during the winter in South Korea. As a result, a recirculating aquaculture system (RAS) was developed to rear parrotfish. This study investigated the effects of stocking density and dissolved oxygen (DO) concentration on the growth and hematology of the parrotfish in the RAS. The experimental stocking densities were 5 (SD05), 10 (SD10), 15 (SD15), and 20 kg/m3 (SD20) total body weight to tank water volume. As the stocking density increased, the mean weight gain, feed efficiency, and specific growth rate tended to decrease. However, SD10 and SD15 did not differ statistically from SD05 in feed efficiency (P>0.05). Although better growth was achieved in SD05, SD10 and SD15 appeared to be acceptable, practically and economically, in terms of feed efficiency. The experimental DO concentration ranges were 3-4 (DO3), 5-6 (DO5), and 7-8 mg/L (DO7). The mean weight gain and survival tended to increase with the DO concentration, but there were no differences among treatments (P>0.05). Although the feed efficiency did not differ among the treatments, the specific growth rates and daily feed intake increased with the DO concentration and were the highest in DO7 (P<0.05). The cortisol concentration was the highest in DO3 (P<0.05), while there was no difference between DO5 and DO7 (P>0.05).

• The Korean Journal of Malacology
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• v.30 no.3
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• pp.219-226
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• 2014

The effects of different stocking densities on the growth and survival rate of the abalone, Haliotis discus hannai, were investigated in marine net cage for two years. Stocking density was set 15, 30, 45 and 60 percentage $(=per.)/m^2$ with share to cross-sectional area per shelter. The primary rearing period (PRP) and the secondary rearing period (SRP) were conducted by a year. One year mean water temperature of PRP and SRS showed the difference about $2^{\circ}C$. In the growth (initial mean shell length of abalone : $36.14{\pm}2.28mm$) of PRP, the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rate (SGR) of the $15per./m^2$ were higher than those of density groups (P < 0.05). Survival rates of all density groups were showed no significant difference. In the growth (mean shell length of abalone : $55.26{\pm}6.93mm$) of SRP, ARG, DGR and SGR of stocking density groups showed no significant difference except for $45per./m^2$ density group. Survival rate in the low-density (15, $30per./m^2$) was more than 70%, and those of the high-density (45, $60per./m^2$) were less than 31% and 9%, respectively. These results showed that the appropriate stocking density for $15per./m^2$ was seven hundred fifty number per one net cage ($2.4{\times}2.4m$), during PRP using 3-4 cm abalone in length. Also for the secondary rearing period, the optimal stocking density (shell length 5-6 cm of abalone) consider with the economical efficiency was determined to be $30per./m^2$, resulting the productivity improved.

• Journal of Aquaculture
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• v.16 no.4
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• pp.257-261
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• 2003

The effects of different stocking densities on the growth of juvenile abalone, Haliotis discus hannai and water quality in the recirculating system with rotating biological contactor, were assessed. The trials were conducted using total weight 32 g juveniles abalone for 60 days at stocking densities of 5, 10, 15 kg/$m^2$. The animals were fed sufficient amounts of the pellet diet of 30.4% protein during the experimental period. Daily feeding rate (DFR) and survival rate (SR) of 5 kg/$m^2$ showed 0.76% and 85.5% those were not significantly differed 10 kg/$m^2$ showing 0.75% and 96.0% (P>0.05). DFR and SR of 15 kg/$m^2$ showing 0.38% and 31.2% were significantly lower than 5 and 10 kg/m2 (P<0.05). Daily growth rate (DGR) and feed efficiency (FE) showed the highest as 0.19% and 24.2% in 5 kg/$m^2$ the lowest as 0.05% and 14.3% in 15 kg/$m^2$ (P<0.05). According to, these results was an inverse relationship between growth and stocking density. The optimum density of juvenile abalone from this experiment is 5 to 10 kg/$m^2$ in the recirculating system.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.209-214
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• 1999

Grazing preference, voluntary dry matter intake, stocking rate and digestibility of forage were investigated or sheep grazed in mature oil palm plantations in Malaysia. Dry matter intake (DMI) was estimated using the chromium sesquioxide marker method. The sheep were allowed to graze about 5 hours/day in oil palm plantations of age ranging from 9 to 21 years old. The crude protein, crude fibre and ash contents of selected herbage were 13.1 %; 24.6 %; and 8.3 %, respectively, while the gross energy (GE) and the metabolisable energy (ME) were 16.9 and 6.0 MJ/kg DM, respectively. Broad leaf plants and grasses were normally found in plantation of all ages. Legumes and oil palm seedlings formed the smallest group in the whole mixture. Fern content increased in older plantations. Legumes, oil palm seedlings, fern, broad leaves and grasses were 0.4, 1.3, 11.4, 28.0 and 59.0 %, respectively of total herbage. Grasses showed the highest preference index followed by broad leaf plants, legumes, oil palm seedlings and ferns in that order. The DMI and the metabolisable energy intake (MEI) of sheep at 6, 8, 10, 12 and 14 months of age were 64.8, 65.0, 65.3, 65.6 and 67.4 g/kg $W^{0.75}$ (p<0.05) and 0.39, 0.40, 0.40, 0.40 and 0.41 MJ/kg $W^{0.75}$, respectively. The average stocking rate was 4.3 sheep/ha. It was concluded that the performance of the sheep could be improved by increasing the daily grazing period and also by appropriate concentrate supplementation.