• Animal cells and systems
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• v.14 no.4
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• pp.315-322
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• 2010

We studied and compared the age structure, body size, and growth rates of field populations of two Korean salamander species (Hynobius yangi and Hynobius quelpaertensis) to elucidate important aspects of basic population dynamics of these two endemic Hynobius species. In both populations, females were sexually mature at three years of age, while H. yangi and H. quelpaertensis males matured at two and three years of age, respectively. Both males and females of H. yangi and H. quelpaertensis attained a maximum age of 11 years and 10 years, respectively. In both species, the snout-vent length (SVL) and body weight (BW) of the females were greater than those of the males. The SVL, BW, and asymptotic SVL of both male and female H. yangi were smaller than those of H. quelpaertensis. The adult growth rates after sexual maturation of male and female H. yangi were lower than those of H. quelpaertensis, possibly resulting in the smaller body size of the former, although overall growth coefficients were not significantly different between the two species. We also compared the age structure and growth rates of three Korean and three Japanese species of Hynobius.

• Korean Journal of Agricultural Science
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• v.51 no.2
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• pp.123-132
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• 2024

Copper sulphate (CuSO₄) level was analyzed in this study to determine the effects on growth performance, nutrient digestibility, organ weight, and excreta score in Ross308-broilers. A total of 1,134 mixed sex, 1-d old Ross-308 chicks were randomly allocated to one of three treatment groups with 21 replication and 18 chicks / cage. For a period of 32 days, chicks were fed with the following treatment groups: CON: Basal diet, TRT1: 0.032% CuSO₄, TRT2: 0.047% CuSO₄ (Phase 1), 0.032% CuSO₄ (Phase 2), 0.025% CuSO₄ (Phase 3). The experiment was divided into three phases. Phase 1 (day 1 to 9), phase 2 (day 9 to 21), and phase 3 (day 21 to 32). During days 1 to 9, broilers receiving 0.032% or 0.047% of CuSO₄ in TRT1 and TRT2, respectively, had significantly higher body weight gain (BWG) (p = 0.042) than CON. Likewise, comparing TRT1 and TRT2 to CON during days 10 to 21, 0.032% of CuSO₄ significantly increased BWG (p = 0.013) and feed intake (FI), (p = 0.024) in the broiler. When compared to TRT1, the administration of 0.032% and 0.025% of CuSO₄ during days 22 to 32 reduced BWG and FI in CON and TRT2, respectively among the treatment groups. Throughout the experiment, the feed conversion ratio (FCR) did not change. However, the nutrient digestibility, weight of organs, and the score of excreta remained unchanged. The study found that CuSO₄ administration increased broiler BWG and FI without affecting FCR, nutrients digestibility, weight of organs, and excreta score.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1074-1080
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• 2017

Objective: The growth, carcass and retail cut yield records on 1,428 Hanwoo steers obtained through progeny testing were analyzed in this study, and their heritability and genetic relationships among the traits were estimated using animal models. Methods: Two different models were compared in this study. Each model was fitted for different fixed class effects, date of slaughter for carcass traits and batch of progeny test live measurement traits, and a choice of covariates (carcass weight in Model 1 or backfat thickness in Model 2) for carcass traits. Results: The differences in body composition among individuals were deemed being unaffected by their age at slaughter, except for carcass weight and backfat thickness. Heritability estimates of body size measurements were 0.21 to 0.36. Heritability estimates of retail cut percentage were high (0.56 from Model 1 and 0.47 from Model 2). And the heritability estimates for loin muscle percentage were 0.36 from Model 1 and 0.42 from Model 2, which were high enough to consider direct selection on carcass cutability traits as effective. The genetic correlations between body size measurements and retail cut ratio (RCR) were close to zero. But, some negative genetic correlations were found with chest girths measured at yearling (Model 1) or at 24 months of age or with chest widths. Loin muscle ratio (LMR) was genetically negatively correlated with body weights or body size measurements, in general in Model 1. These relationships were low close to zero but positive in Model 2. Phenotypic correlation between cutability traits (RCR, LMR) and live body size measurements were moderate and negative in Model 1 while those in Model 2 were all close to zero. Conclusion: Therefore, the body weights or linear body measurements at an earlier age may not be the most desirable selection traits for exploitation of correlated responses to improve loin muscle or lean meat yield.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.1038-1047
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• 2008

This study aimed at targeting fixed increases in body weight (100 g/wk) by quantitatively regulating energy allowances (ME) in broiler breeders from 5 to 20 wks of age. Four energy regimes were tested: 1. The energy required for maintenance, activity and growth was calculated for 100 g increases in body weight/wk and a measured quantity of grower diet (160 g protein and 2,600 kcal ME/kg) was offered to the control group (ME-100) to achieve the anticipated weight gain. The energy allowances increased with age from 132 to 294 kcal/d. 2. Additionally, three energy regimes were considered, quantitatively reducing ME by 10% (ME-90) or 20% (ME-80) and increasing by10% (ME-110) over the control group. Each test group had 23 replicates5 female chicks housed in cages. The influence of energy regimes and age on growth, nutrient digestibility, carcass attributes, bone parameters and stress was evaluated at 4 wk intervals. Quantitative ME restriction by 10% (119-265 kcal/d) produced an average weight gain of 98.1 g/wk, which was closer to the targeted increase of 100 g/wk, whereas the control group attained it nine days earlier. Restriction of energy by 10 or 20% produced better conversion efficiency of feed, energy and protein and apparent digestibility of protein, Ca and P than 10% excess ME. Energy regimes did not influence eviscerated meat yield, but higher energy allowances (ME-110) significantly increased abdominal fat pad and liver weights and decreased giblet weight, percent muscle protein and tibia ash. Relatively higher stress was recorded in ME-restricted groups, as reflected by wider heterophil and lymphocyte ratios and increased bursa weight. Early age (5-12 wk) significantly influenced bone mineralization, conversion efficiency of feed, energy and protein and apparent digestibility of protein, Ca and P, while later ages (13-20 wk) increased eviscerated meat yield, abdominal fat, tibia weight and muscle protein and reduced stress. Energy regime x age interactions were significant and are discussed. In conclusion, the synthetic broiler line used in our study responded positively to controlled energy feeding during the rearing period. Breeders offered 119-265 kcal/d, a reduction of 10% energy over the control group, were more effective in regulating grower performance than the latter. In addition to energy regimes, age intervals also exhibited significant influence on specific parameters during the grower phase.

• Journal of Aquaculture
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• v.22 no.1
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• pp.118-121
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• 2009

This experiment was conducted to evaluate the effects of different substrates in rearing tank on growth and body composition of juvenile sea cucumber Apostichophus japonicus. Sea cucumber (average weight 3.6) were randomly distributed at a density of 10 juvenile per tank into nine tanks providing three different substrates including free-substrates, sand and wave-shaped plastic sheet as (shelter). Juveniles were fed with a commercial feed once in every 2 days for 8 weeks. At the end of the experiment, survival of sea cucumber was not affected by the presence of substrates (P>0.05). Weight gain and specific growth rate of sea cucumber reared in the tanks with sand were significantly higher than those of sea cucumber reared in the tanks with shelter and without substrate (P<0.05). Crude protein and crude lipid of whole body in sea cucumber reared in free-substrate tanks were significantly higher than those of juvenile reared in the tanks with other substrates (P<0.05). Higher ash content was obtained in sea cucumber reared in the tanks with sand compared to that of juvenile reared in the tanks with other substrates (P<0.05). The results of this study suggest that growth and proximate composition of whole body of sea cucumber was significantly affected by substrates. Among materials tested, sand may be a proper substrate for sea cucumber culture.

• Journal of Dairy Science and Biotechnology
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• v.28 no.1
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• pp.53-59
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• 2010

The milk product is one of the major foods which provide calcium for nutritional requirement. In addition to calcium, it supplies diverse nutrients including protein, potassium, vitamin A, vitamin $B_1$, and vitamin $B_2$. Adequate calcium intake throughout lifetime ensures optimum bone density and prevents osteoporosis in old age by reducing loss of bone mineral during growth and aging. The nutritional deficiency of calcium intake and spreading of osteoporosis in Korean population accentuated necessity of adequate calcium intake through milk consumption. Obstruction of milk consumption due to lactose intolerance should be overcome by educational programs for adequate milk consumption and low-lactose milk product developments. Consumption of milk products was reported to prevent high blood pressure in clinical studies and epidemiological investigations. As the feeding of milk increased, the body weight and fat of animal decreased in animal studies. The epidemiological investigations revealed that there was a negative correlation between the amount of milk consumption and the body fat. When calcium was provided as dietary supplement in the clinical trials, the body weight and body fat of subjects decreased. When calcium was particularly supplied as a part of milk, the body weight reduction rate was augmented. Calcium, vitamin D, and conjugated linoleic acid have been reported to exert a role in reducing cancer. The paramount importance of milk in nutrition as a source of calcium and other invaluable nutrients emphasizes consistent supply of milk products to adults as well as adolescents by dairy industry.

• Korean Journal of Veterinary Research
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• v.50 no.4
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• pp.297-302
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• 2010

This study was conducted to investigate the effects of feeding probiotics (gene modified yeast) on the growth performances in pigs. In pigs, this study investigated the effects of dietary probiotics which contained antibacterial probiotics (OR-7, bacteriocin, gene modified yeast) on growth performances and feed efficiency in pig farm. A total of 150 pigs were studied. The treatments are probiotics yeast (PY) 0.3% (basal diet + 0.3% plasmid modified probiotics), PY 0.5% (basal diet + 0.5% plasmid modified probiotics), yeast (Y) 0.3% (basal diet + 0.3% probiotics), Y 0.5% (basal diet + 0.5% probiotics) and control (basal diet). Weight gain, feed intake and feed efficiency were periodically recorded for 90 days. The treatment group trended higher weight gain, feed intake and feed efficiency than control. And, the PY group trended higher weight gain, feed intake and feed efficiency than Y group.

• The Korean Journal of Physiology
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• v.25 no.1
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• pp.81-85
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• 1991

At the fifth day after right lung pneumonectomy in New-Zealand white rabbits $(0.8{\sim}1.1\;kg\;B.W.)$, phospholipid and protein concentration in the left lung lavage fluid were measured for clarification of the effect of unilateral pneumonectomy on the secretory function of the type II pneumocytes in growing rabbits. In an attempt to evaluate the effect of unilateral pneumonectomy on the compensatory growth of the residual lung, left lung weight and left lung weight-body weight ratio and DNA concentration, RNA/DNA and total DNA content in the left lung tissue were measured in pneumonectomized and in sham operated control rabbits. The lung weight of pneumonectomized rabbit was approximately two times heavier than that of the control rabbits. DNA concentration and RNA/DNA of the lung tissue were not changed but total DNA content was increased significantly. Phospholipid concentration in the lung lavage fluid of the pneumonectomized rabbits was over two times higher than that of control rabbits. from these experimental results, It is concluded that unilateral pneumonectomy in growing rabbits might cause to increase the secretion of pulmonary surfactant from type II pneumocyte of the residual lung. The cellular hyperplasia seems to be the primary response of the compensatory growing lung in unilateral pneumonectomized growing rabbits.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.417.2-418
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• 2002

The rhGH-loaded PLGA microsphere formulation was prepared using a double emulsion process from hydrophilic 0:50 poly(D.L-lactide-co-glycolide) (PLGA) polymers. To investigate the sustained efficacy of this formulation, ts pharmacodynamic characteristics were analyzed. It showed particle size of ca 53.1 $\mu\textrm{m}$ with high drug ncorporation efficiency and it was sucutaneously administrated to hypophysectomized rats and whole body rowth responses of this formulation were compared to those of the different dosing patterns of rhGH. (omitted)

• Journal of the Korean Society of Safety
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• v.11 no.3
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• pp.177-187
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• 1996

This paper is concerned with the comparison and chronological changes of the physical constitution of the Korean youth, age range 6-17. For the purpose, anthropometric data of schoolchildrens are surveyed from the Statistlcal Yearbook of Education published in Ministry of Education. The results show that body dimensions have increased consistently from 1964 to 1994. During the last 30years, stature has increased by about 1cm to 6cm per decade, on the average, and body weight has increased by about 1kg to 5kg per decade. On the other hand, silting height and chest circumference have increased by about 0.5cm to 3cm per decade. The results also show that there are significant sex differences in the characteristics of physical growth. These findings identified in this study mean that boys and girls have essentially different requirements for the design of the workplace.