• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.1
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• pp.49-59
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• 2017

The objective of this study was to investigate the growth rate and the optimal stocking density of sea cucumbers. Grow-out was studied in situ by conducting a follow-up survey using visible implant elastomer (VIE) tags. The rearing systems were made of polypropylene pipe for the frames and netting. The experiment ran for 70 days near Yeosu, Korea in the water depth of about 7 m. A total of 576 sea cucumbers which have three groups of body sizes (small: 5.15, medium: 12.34 and large: 23.26 g) were used. The five groups of stocking densities (150, 300, 450, 600 and $850g/m^2$) in rearing system for sea cucumber were considered. Sea cucumbers were fed a mixed diet (mud, mineral, fish meal, etc.). The feed was supplied to 10% of their body wet weight once every 7 days. The survival rate (73%) of sea cucumber in $850g/m^2$ was lower than those of other density groups ($150g/m^2$: 89%, $300g/m^2$: 84%, $450g/m^2$: 78% and $600g/m^2$: 86%). The survival rate of medium size group was higher than those of small and large groups regardless of the density (P<0.05). Most of density groups have no significant difference except for $850g/m^2$ (P>0.05). The growth rate of small size group ($0.63%day^{-1}$) was higher than those of medium ($0.38%day^{-1}$) and large ($0.34%day^{-1}$) group regardless of the density (P<0.05). The threshold water temperature was $11.0^{\circ}C$ for sea cucumber growth in winter season.

• 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.

• Food Science of Animal Resources
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• v.35 no.6
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• pp.715-720
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• 2015

This study was conducted to determine the effects of beak trimming, stocking density (D) and sex (S) on live weight (LW), carcass yield and its component, and plasma glucose (PG) and triglyceride levels in Large White turkeys. To accomplish this aims, totally 288 d old large white turkey chicks (144 in each sex) were used. Beaks of 77 male and female poults were trimmed when 8 d old with an electrical beak trimmer. The birds were fed by commercial turkey rasion. Experiment was designed as 2 × 2 × 2 factorial arrangement with 3 replications in each group. Beak trimming and stocking density did not affect live weight, carcass composition and its components. The higher LW and carcass weight observed in trimmed groups. As expected, male birds are heavier than female, and carcass percentage (CP) would be adverse. However, in this study, CP of male was higher in trimmed, in 0.25 m²/bird. (D) × sex (S) interaction had an effect on both CP and thigh weights (p<0.05). Significantly D × S was observed in LW, CP and PG. The weight of carcass and its some components were higher in male. S × D interaction had an effect on plasma glucose level (p<0.05). Triglyceride level was affected (p<0.05) by sex. Significant relationships were found between percentage of thighs (r=0.447, p<0.01) and percentage of breast (r=0.400, p<0.01). According to this study, it can be said that trimming is useful with density of 0.25 m²/bird in turkey fattening.

• Korean Journal of Poultry Science
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• v.48 no.1
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• pp.13-22
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• 2021

The present experiment was conducted to evaluate the effect of stocking density on the growth performance, immune status, and meat quality of broilers. In total, 385 one-day-old Ross 308 broilers were randomly assigned to one of four distinct stocking densities: 26 birds/㎡, 22 birds/㎡, 19 birds/㎡, and 16 birds/㎡. They were fed the diet ad libitum for 5 weeks. Immunoglobulin (Ig) and corticosterone levels were evaluated, and growth performance, blood parameters, and breast meat quality were determined. It was observed that the weight gain and feed intake of growers (21~35 d) and broilers (0~35 d) were significantly reduced as the stocking density increased (P<0.05). However, the feed intake of starters (0~21 d) significantly increased as the stocking density increased (P<0.05). There were no significant differences in the biochemical profiles among the four different stock densities. Furthermore, no significant differences were observed in the stress parameters: (heterophils / lymphocytes ratio and corticosterone), IgA, and IgM; however, IgG significantly increased with stocking density (P<0.05). The pH, water holding capacity, and cooking loss of the muscle were all unaffected by the stocking density, but the shear force (tenderness) increased slightly as the density increased. The findings of this study suggest that a lower stocking density (16 birds/㎡) significantly improved the shear force of breast meat and IgG in broilers.

• Journal of Environmental Science International
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• v.31 no.4
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• pp.369-372
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• 2022

This study was conducted to determine the injury type and frequency of bearded dragons during single and group breeding according to stocking density, for 16 weeks. A total of 14 bearded dragons compromising three groups were selected for this study. Six and four bearded dragons bred in a cage of 45 cm × 45 cm × 45 cm were designed as group A and B, respectively. Group C was made of four partitions (20 cm × 20 cm × 20 cm) of equal size in the kennel, and the dragons, four in number, were reared alone. Injury type criteria were given 1 score each in 6 stages. Most of the injury types in group A were primary tail cutting, which was 1 point, depending on the score, except for 4 scores. The injury type of group A varied, that is 1, 2, 3, and 5 scores, and the pattern lasted for 2 to 9 weeks. After 10 weeks, the dragons showed no response to injury type, except 4 scores at 11 weeks and 2 scores at 14 weeks with a frequency of one, respectively. The representative injury types of the group B were primary tail cutting, which was 1 point, and the scores of the injury type from 2 to 11 weeks were the highest; the frequency of occurrence at 1 and 2 scores was 5 times and 3 times, respectively, and the frequency of occurrence at 3 scores was twice. In addition, 5 scores were found to have the lowest frequency of occurrence. Solitary breeding showed no response to the type of injury for 16 weeks. Consequently, single breeding with an appropriate stocking density did not affect stress, and it could be expected a positive aspect for pet welfare.

• 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 Agricultural Science
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• v.50 no.4
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• pp.861-867
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• 2023

Lairages serve several functions, such as providing post-mortal inspections and providing a reservoir of animals to ensure the slaughter line runs efficiently. High stress lairage conditions can contribute to the accumulation of transport stress in pigs, causing poor pork quality and still stressed pigs at slaughter. The objective of this study was to investigate meat quality, blood profile and behavior changes according to lairage stocking density in in high temperature. Density treatments were as follows: LD, low density (lower than 0.5 m²/100 kg); ND, normal density (0.5 m²/100 kg to 0.83 m²/100 kg); HD, high density (higher than 0.83 m²/100 kg). Air temperature treatment was as follows: HT, high temperature (higher than 24℃). Pigs stocked with LD showed lower pH, WHC (water holding capacity), and higher DL (drip loss) and CL (cooking loss) than those stocked with HD. Pigs stocked with LD showed lower cortisol level than those stocked with HD. Therefore, Pigs exposed to high stock density (lower than 0.5 m²/100 kg) in high air temperature during pre-slaughter caused acute stress and lead to PSE (pale, soft, exudative) pork incidence. Based on obtained results, stocking of too high (lower than 0.5 m²/100 kg) density is generally not good for meat quality and animal welfare at high temperatures.

• Korean Journal of Poultry Science
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• v.38 no.1
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• pp.1-4
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• 2011

A 35-day trial was conducted to examine the influence of floor density on the behaviour of broiler chickens. Day-old male broilers (n=756) were randomly assigned to one of four stocking densities (6 replicates of n=13, 25, 38 and 50) in 24 identical 2.6 $m^2$ pens. These stocking densities were coded very low (VL), low (L), medium (M) and high (H) and contained a floor space allowance per bird of 2,000 $cm^2$, 1,000 $cm^2$, 667 $cm^2$ and 500 $cm^2$, respectively. Scan sampling of all groups was carried out at 15-min intervals during two 1-h periods (10.00 h~11.00 h and 14.00 h~15.00 h) for five days each week. The numbers of birds engaged in different behavioural activities were recorded. It was found that the most common behaviour in all densities was lying. There was no clear effect of density during wks 1~4 of the trial, but in wk 5 birds in the L, M and H groups showed lower levels (P=0.07) of lying behaviour when compared to birds in the VL group suggesting that an increase in animal density results in decreased opportunities for undisturbed rest. This observation is supported by standing and walking behaviour, which was lower (P<0.05) in the VL group in wk 5. Foraging behaviour measured in the study by the numbers of birds pecking the ground declined as the trial progressed, but scratching increased in 2 wk then decreased. Birds in the VL group showed higher (P<0.05) level of pecking the ground behaviour compared to birds in the L, M and H groups, but scratching behaviour higher (P<0.05) and lower (P<0.05) in VL of 1 wk and 2 wk respectively. However, a peak in aggressive behaviour was observed in wk 2 and birds in the VL group showed less (P<0.05) agonistic behaviour than birds in the H and M groups. Other behaviours (dustbathing, preening, eating or drinking) were not influenced (P>0.05) by stocking density.

• The Journal of Fisheries Business Administration
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• v.42 no.3
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• pp.79-93
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• 2011

Water temperature of Oliver flounder farm affects Oliver flounder growth and mortality rate. In laboratory experimental tanks, optimal water temperature was $22.5^{\circ}C$($21{\sim}24^{\circ}C$) and cultivatable water temperature was $12{\sim}28^{\circ}C$. The purpose of this study is to identify applicable and useful water temperature of Oliver flounder farm in case of actual farming. The data applied in the analysis was collected from Jeju island. In the study, various analytical methods including productivity analysis, regression analysis, statistical analysis were conducted for 13 Oliver flounder culture farms. The result of analysis can be summarized as follows : First, growth rate on the Oliver flounder culture farms was related to mean of water temperature, variation of water temperature and low water temperature. Second, survival rate on the Oliver flounder culture farms was related to mean of water temperature. In case of including Oliver flounder stocking density, defined as the surface area of Oliver flounder per $m^2$ of water surface area, survival rate strongly related to mean of water temperature, variation of water temperature, cultivating capability and stocking density. Third, production weight per $m^2$ of water surface area was strongly related to mean of water temperature, low water temperature and cultivating capability. Growth rate and survival rate was analyzed into mediate variable character.

• ALGAE
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• v.29 no.3
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• pp.217-225
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• 2014

Land-based seaweed (Gracilaria) cultivation systems may provide products with high quality and biosafety for human consumption, as well as for other high value applications. However, a limitation for this land based system is high management costs. The objective of this study was to determine if the management costs for Gracilaria cultivation can be reduced without a decrease in productivity by using $CO_2$ injection along with a high stocking density and high photosynthetically active radiation (PAR), and commercially available fertilizers. When Gracilaria tikvahiae was cultivated at a high stocking density and high PAR, coupled with $CO_2$ enhancement, the productivity was significantly higher than that at a lower stocking density, low light without $CO_2$ injection. We also found that G. tikvahiae grown in a medium of commercially available fertilizer (Jack's Special, JS) showed a similar growth rate and productivity to that grown in von Stosch's enriched (VSE) seawater, while the cost for JS media is only 2% of the cost for VSE. These results suggest that $CO_2$ injection and commercial fertilizer may be a potential way to provide sustainability in land-based Gracilaria cultivation systems.