• The Journal of Fisheries Business Administration
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• v.42 no.2
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• pp.85-96
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• 2011

Oliver flounder population density affect Oliver flounder growth and mortality rate. In laboratory pilot experiment, Oliver flounder growth rate is inversely proportional to stocking density. But previous study has not proved external validity. This study is aimed to analyze the effect of stocking density on the Oliver flounder culture farms in Jeju Island. In order to do this, I selected 13 farms in Jeju island as a sample. 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, in case of the Oliver flounder culture farms, Bertalanffy equation is not applicable to the Oliver flounder growth. Second, the Oliver flounder stocking density, defined as the surface area of Oliver flounder per $m^2$ of water surface area, is preferred to density definition defined as the weight of Oliver flounder per $m^2$ of water surface area on the Oliver Flounder Culture Farms case. Third, growth rate and production weight on the Oliver flounder culture farms are inversely proportional to stocking density on spearman rank correlation test. When extensive comparable biological and culture condition data become available, analysis model can be easily modified to yield more accurate results.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.901-907
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• 2016

The present study investigated stocking density and genetic lines, factors that may alter the severity and incidence of angel wing (AW), in White Roman geese. Geese (n = 384) from two genetically selected lines (normal- winged line, NL, and angel-winged line, AL, respectively) and one commercial line (CL) were raised in four pens. Following common commercial practice, low-stocking-density (LD), medium-stocking-density, and high-stocking-density treatments were respectively administered to 24, 32, and 40 geese per pen at 0 to 3 weeks ($1.92m^2/pen$) and 4 to 6 weeks ($13.2m^2/pen$) of age and to 24, 30, and 36 geese at 7 to 14 weeks ($20.0m^2/pen$) of age. The results revealed that stocking density mainly affected body weight gain in geese younger than 4 weeks, and that geese subjected to LD had a high body weight at 2 weeks of age. However, the effect of stocking density on the severity score of AW (SSAW) and incidence of AW (IAW) did not differ significantly among the treatments. Differences were observed among the genetic stocks; that is, SSAW and IAW were significantly higher in AL than in NL and CL. Genetic selection generally aggravates AW, complicating its elimination. To effectively reduce IAW, stocking density, a suspected causal factor, should be lower than that presently applied commercially.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1553-1558
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• 2012

This study was conducted to investigate the effects of stocking density or group size on feed intake, daily gain, and carcass characteristics of Hanwoo (Korean indigenous breed) steers reared from 7 months to 31 months of age. Thirty Hanwoo steers were divided into four groups with three replicates each (a total of 12 pens). In each group, one (G1), two (G2), three (G3), and four steers (G4) per pen were allocated as treatments. Pen size was $32.0m^2$, and therefore Hanwoo steers in G1, G2, G3, and G4 were reared under different space allowances, i.e. 32.0, 16.0, 10.6, and $8.0m^2$/steer, respectively. Steers were reared following a conventional beef cattle management method in Korea, and were offered a fixed amount of commercial concentrate with ad libitum forages. Results were subjected to analysis of variance with stocking density as the main effect, and significance was declared at p<0.05. Although total feed intake was not significantly altered, it numerically increased in animals of low stocking density (G1) compared to those subjected to high stocking density treatment (i.e. G4). Feed conversion ratio was higher (p<0.05) in G3 compared to G1 and G2. Animals in G1 (low stocking density) grew faster (p<0.05) than those of high stocking density (G3 and G4). Back fat thickness, meat yield index, and meat yield grade were similar among all levels of stocking density. However, longissimus muscle area was larger in G1 and G2 (p<0.01) compared to G3 and G4, and animals in G3 produced smaller carcasses (p<0.05). Carcass quality traits, including marbling score, meat color, fat color, texture, maturity and meat quality grade, as determined by a group of experts, were not significantly different among the treatments. In conclusion, lower stocking density resulted in increased feed efficiency, daily gain, and carcass weight in Hanwoo steers. However it remains unclear whether such differences are the results of stocking density or group size, or a combination of both. Nonetheless, these results confirm previous studies reporting a negative effect of increased stocking density on animal productivity. Further, animal welfare under an intensive farming system in relation to economical return is discussed.

• Korean Journal of Poultry Science
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• v.41 no.3
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• pp.205-215
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• 2014

The aim of this study was to determine the effects of stocking density and strain on the performance and physiological adaptive responses including the plasma corticosterone content and the level of mRNA expression of pro-inflammatory cytokines and antioxidant enzymes in broiler chicks. A total of 300 birds of two strains (150 Ross strain vs. 150 Cobb strain) aged 3-d old were allotted into two stocking densities (standard stocking density,$0.046m^2/bird$ vs. high stocking density, $0.023m^2/bird$) in battery cages by $2{\times}2$ factorial designs with ten replicates until 35 d of age. There was no significant strain effect on body weight, feed intakes and feed to gain ratio and the relative organ weights. However body weight, feed intakes and relative organ weight were found to be significantly (P<0.05) affected by the effect of stocking density. Plasma corticosterone level was not affected by both stocking density and strain effects. Hepatic mRNA expression of pro-inflammatory cytokines including interleukin-$1{\beta}$ (IL-$1{\beta}$), IL-6, IL-18 and interferon-gamma (IFN-${\gamma}$) was not significantly changed by the effects of strain and stocking density. However, the mRNA expression of glutathione peroxidase (GPX) was affected by strain, showing that Ross strain decreased (P<0.05) the GPX expression. With respect to the effect of stocking density, there was a significant (P<0.05) increase in superoxide dismutase (SOD) and catalase (CAT) and GPX mRNA expression in the liver from high stocking density group. Splenic pro-inflammatory cytokine expression was not also affected by stocking density and strain, except that IL-18 mRNA significantly (P<0.05) decreased in Cobb strain under high stocking density. The mRNA expression of SOD and CAT was significantly (P<0.05) affected by the effects of stocking density and strain. In conclusion, growth performance was not affected by strain but stocking density. Although mRNA expression of major pro-inflammatory cytokines was not changed by stocking density and strain, antioxidant enzyme was significantly affected by stocking density, strain or even organ in birds under summer conditions. More detailed studies still needed to be explored to elucidate the effects of environmental conditions and genetic background on physiological responses in birds.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.2
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• pp.241-246
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• 2013

This study was conducted to evaluate the effects of dietary vitamin levels and stocking densities on growth performance, nutrient digestibility, and blood characteristics in growing pigs. A $2{\times}3$ factorial (two vitamin levels, three regimens of stocking densities) arrangement was utilized with 96 pigs ($23.10{\pm}0.95$ kg initial body weight and 63 d of age) for 36 d. The pigs were allocated to pens with different stocking density (0.64, 0.48, and 0.38 $m^2/pig$, respectively). The diets used in this study were a normal diet (based on NRC) and a high level of vitamin diet (2-fold higher than normal diet). The ADG and ADFI of pigs were decreased as the stocking density increased (p = 0.03 and p = 0.01, respectively). The G/F of pigs was 5% lower in the high vitamin treatment (p = 0.03) as compared with the control treatment. The apparent total tract digestibility (ATTD) of DM and N digestibility was negatively affected by the high level of vitamin in diets (p = 0.05 and p = 0.04, respectively). Moreover, a significant and negative effect on the ATTD of N was detected in the large groups (linear, p = 0.02). Blood cortisol concentration was increased with increasing stocking density (linear, p = 0.05), and was decreased by high level of vitamin (p = 0.04) at the end of this experiment. Stocking density also caused a linear reduction in WBC concentration (p = 0.05). Our data indicated that the principal effect of stocking density was not reliant on dietary vitamin levels. In conclusion, results indicated that doubling the vitamin supplementation did not improve the growth performance of pigs in high density. However, the blood cortisol concentration was decreased but the ATTD of N digestibility was impaired by high level of vitamin diet.

• 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 Poultry Science
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• v.46 no.4
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• pp.297-304
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• 2019

This study evaluated the effects of stocking density on performance and behavioral activities of 35-day-old broilers in relation to incandescent white bulb (IB) light and LED yellow and white light. A total of 1,650 day-old chicks were weighed and randomly allocated into six treatment groups in a 2 × 3 factorial arrangement based on stocking density (14 birds m^-2 and 22 birds m^-2) and color of lights (IB; monochromatic LED yellow and white light) with five replicates for each treatment. The results showed that final body weight, weight gain and feed conversion of broilers were improved at a stocking density of 14 birds m^-2 with exposure to LED lights. Similarly, broilers spent more time exhibiting inactive behavior (e.g. standing) and active behaviors (e.g. walking and walking plus pecking) under 14 birds m^-2 with exposure to lights as compared that of other treatment groups. Regarding a stocking density of 22 birds m^-2, broilers performance traits were negatively affected and also activities were less. The performance of broilers was not significantly altered for the main factor of different lights but broilers were less inactive (e.g less time spent sitting plus standing) and more time spent active behavior in walking under IB light than LED light. Thus, we concluded that a stocking density 14 birds m^-2 with exposure to LED light significantly improved broiler performance and behavioral activity and these conditions could therefore improve the overall welfare of farmed chickens.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.1
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• pp.58-63
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• 2011

This study investigated the effects of stocking density and feeding frequency (three and five times per week) on the growth of Pacific cod, Gadus macrocephalus. In the first experiment, experimental groups of fish (mean weight $167.8{\pm}41.4\;g$) were reared at three stocking densities (4, 8 and 12 kg/$m^3$) for 16 weeks. The total weight gain was 17.8, 17.1 and 35.4% at 4, 8 and 12 kg/$m^3$, respectively. The specific growth rates, survival rates and feeding efficiency increased with the density, but there were no significant differences (P>0.05). The daily feed intake decreased as the stocking density increased, whereas the condition factors increased with the stocking density (P<0.05). In the second experiment, groups of fish ($194.1{\pm}68.3\;g$) were fed either three or five times a week. The total wight gain was 14.4 and 18.5% for the fish fed three and five times per week, respectively. The specific growth rates of Pacific cod fed to satiation increased with the feeding frequency, although the difference was not significant (P>0.05). The survival rates, daily feed intake, feed efficiency, and condition factors of the Pacific cod were not significantly different (P>0.05). Based on these results, the optimum stocking density for juvenile cod is above 12 kg/$m^3$, and the best feeding frequency is three times a week, under the conditions used in this experiment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.762-769
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• 2017

This study investigated the effects of stocking density on the growth of the mandarin fish Siniperca scherzeri, in small (1-year old, 50.2 g/fish) and large (2-years old, 173.1 g/fish) size (age) groups. Small and large fish groups were fed pelleted diets twice daily for 10 and 15 weeks, respectively. In the small group, at the end of the feeding, the weight gain of fish at a density of $4kg/m^3$ was lower than that of fish at densities of 3, 2 and $1kg/m^3$. However, fish stocking density did not affect feed efficiency. The daily feed intake of fish at a density of $4kg/m^3$ was lower than that fish at densities of 3, 2 and $1kg/m^3$. In the large fish group, the weight gain of fish at a density of $4.5kg/m^3$ was higher than that of fish at densities of 6, 3 and $1.5kg/m^3$. Again, fish stocking density did not affect feed efficiency. The daily feed intake of fish at a density of $4.5kg/m^3$ was higher than that of fish at densities of 6, 3 and $1.5kg/m^3$. Based on these results, the optimum stocking density for small (50.2 g/fish) and large (173.1 g/fish) mandarin fish is 3 and $4.5kg/m^3$, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.707-712
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• 2014

The effects of transport stocking density (500, 600 and 700 kg of olive flounder Paralichthys olivaceus/per water tank) on the physicochemical characteristics of muscle were investigated. Transport of the animals took, on average, 10 days from Busan, Korea, to Long Beach, CA, USA. There was no significant difference in the breaking strength of muscle among the three groups. There was also no significant difference in the ATP, lactate, or glycogen content of muscle from the 500 and 600 kg/tank stocking density groups at the beginning and after transport. However, the ATP content decreased sharply while the lactate content increased in muscle from fish transported at a density of 700 kg/tank at the beginning of transport, and the ATP and lactate contents in this group were stable after transport.