• 생명과학회지
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• 제8권3호
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• pp.272-278
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• 1998

UV-B 강도 변화가 식물의 생장에 미치는 영향을 조사하기 위하여, 오이를 이용하여 3주간 3단계의 UV-B[일일 평균 UV-$B^{BE}$; 무처리(0.03), 저UV-B(6.40), 고UV-B(11.32) kJ $m^{-2}$]조사 실험을 수행하였다. 3주간의 UV-B 조사에 의해 건물중 및 엽면적은 고UV-B 처리와 저UV-B 처리에서 각각 60%와 40% 정도의 감소를 보였으나, 엽중비는 증가하였다. UV-B에 의해 고UV-B 처리에서 약 45%, 저UV-B 처리에서 약 37%의 광합성속도의 감소를 나타내었으나 증산속도의 변환느 나타나지 않았다. 총 엽록소 함량은 UV-B 강도의 증가에 따라 감소하였으며, UV-흡수물질인 flavonoid의 함량은 고UV-B 처리에서 약 19% 저UV-B처리에서 약 14%의 증가를 보였다. 이상의 결과로 볼 때 UV-B조사는 오이 식물에 극심한 생육 저해를 나타내었으며, 그 피해는 UV-B 강도에 따라 증가하였다. 따라서 현재 지구에 도달하는 태양UV-B에 의해서도 오이식물은 영향을 받고 있는 것으로 사료되며, 장래 예상되는 오존층 감소에 의해서도 생육장해를 나타낼 것으로 사료된다.

• 한국수산과학회지
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• 제47권5호
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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.

• Fisheries and Aquatic Sciences
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• 제19권5호
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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.

• 한국식품위생안전성학회지
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• 제16권2호
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• pp.139-144
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• 2001

밀과 보리의 방사선 조사 여부를 검지하기 위해 생물학적 방법인 발아법을 이용하였다. 곡류의 순과 뿌리 성장은 0.3 kGy에서도 상당히 억제되므로 0.5 kGy 이하의 저선량으로 감마선 조사하였고 순과 뿌리 길이를 측정하여 성장정도를 확인하였다. 밀의 순은 모든 선량에서 5일 동안 지속적인 성장을 하였지만 0.1 kGy조사시료를 제외하고 조사선량이 증가할수록 길이가 짧아지거나 성장정도가 감소하는 경향을 보여 비조사 시료와 조사 시료의 구분이 가능하였다. 밀의 뿌리는 비조사 시료의 길이 성장정도가 조사 시료들보다 컸으며 3일째 뿌리의 길이가 20mm에 가장가깝게 성장하였으므로 이를 기준하여 조사여부를 판정하였다. 보리의 경우 순과 뿌리 모두 조사선량이 증가할수록 성장이 지연되었다. 순은 0.3 kGy 이상 조사 시료에서 조사선량이 증가할수록 5일간의 성장정도가 점차 감소하여 비조사 시료와 조사시료의 구분이 가능하였고 보리의 뿌리는 3일부터 조사 시료들과 비조사 시료들간에 차이를 보이면서 5일째에는 0.3 kGy 이상 조사 시료들과 비조사 시료들간에 통계적으로 유의한 차이를 보였다. 보리의 방사선 조사 여부의 판별은 뿌리가 3일 째 20mm에 가장 가깝게 성장한 것과 5일 동안 성장정도가 가장 큰 것을 기준하여 비조사 시료와 조사 시료를 판별할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1390-1393
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• 2006

Data spread over 11 years (1986-1996) pertaining to a synthetic population developed by inter se mating of half-breds of Corriedale and Russian Merino with Nali maintained at CCS Haryana Agricultural University, Hisar were utilized for the estimation of genetic parameters for growth traits. The means for birth weight (BWT), weaning weight (WWT), six month body weight (SWT), yearling weight (YWT), preweaning daily gain (PRW) and post weaning daily gain (POW) were 3.35 kg, 10.79 kg, 13.28 kg, 18.96 kg, 82.6 gm and 27.6 gm, respectively. The effects of year and season of birth and sex of lamb were significant for all the traits under study except the effect of season of birth for WWT, SWT and PRW. No definite trend was observed over the years for the averages of body weight and gain. Lambs born during the spring season performed better for BWT, WWT and PRW while the performance of lambs born during autumn was better for the other traits included in the study. The male lambs were heavier than the females for body weight at all stages and gain in weight. The heritability estimates for WWT and PRW were low; for BWT and SWT were moderate and for YWT and POW were high. Birth weight had high heritability and high genetic correlations with subsequent body weights and gains but due to the presence of a maternal effect on BWT and WWT, a sequential selection procedure is recommended for the improvement of growth rate in sheep.

• Asian-Australasian Journal of Animal Sciences
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• 제30권3호
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• pp.386-391
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• 2017

Objective: Protein supplementation is costly and can result in excess nitrogen (N) excretion. The objective of this study was to evaluate the effects of feeding different levels of dietary protein on average daily gain, body size, rumen fermentation, and nitrogen excretion of 8 to 10 month-old Holstein heifers. Methods: Thirty-six Holstein heifers were divided into 12 blocks according to age ($273{\pm}6.2d$) and were randomly assigned to diets containing a low (10.2% dry matter [DM]), medium (11.9% DM), or high (13.5% DM) level of dietary crude protein (CP). All diets contained approximately 70% roughage and 30% concentrate with similar dietary metabolizable energy (ME) content (2.47 Mcal/kg). Results: Dry matter intake did not differ among the treatments, and average daily gain increased with the increasing dietary protein, 0.79, 0.95, 0.97 kg/d for low, medium, and high group, respectively. Body height increased linearly with increasing dietary CP but no other significant differences in body dimensions were found among the treatments. The increased ratios of dietary CP improved the rate of rear teat length growth remarkably (p<0.05). There was no difference in rumen pH or ruminal major volatile fatty acid (acetate, propionate, and butyrate) concentration among the 3 diets, but rumen ammonia-N concentration increased with the higher dietary CP (p<0.05). Increasing N intake led to increased total N excretion; urinary N excretion was significantly increased (p<0.05) but fecal N excretion was similar among the treatments. Conclusion: These data suggest that the diet containing 11.9% CP (ME 2.47 Mcal/kg) could meet the maintenance and growth requirements of 9 to 11 month-old Holstein heifers gaining approximately 0.9 kg/d.

• Animal Bioscience
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• 제35권4호
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• pp.596-604
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• 2022

Objective: To investigate the effects of enzyme-bacteria co-fermented feed on broilers, the basal diet (BF) was pretreated by microbial enzyme co-fermentation, and then different proportions of BF were replaced to study its effects on growth performance, nutrient metabolism and cecal microflora of broilers. Methods: Four hundred and eighty 1-day-old broilers were randomly divided into 6 groups. The control group was fed with BF, and groups 1 to 4 were treated with dried fermented feed (DFF) instead of 10%, 15%, 20%, and 25% the BF, and group 5 was treated with wet fermented feed (WFF) instead of 10% the BF, named BF, 10% DFF, 15% DFF, 20% DFF, 25% DFF, and 10% WFF, respectively. The trial period was 42 days. Results: The results showed that the average daily feed intake and average daily gain of 10% DFF, 15% DFF, and 10% WFF groups were significantly higher than those of the control group at 22 to 42 days and 1 to 42 days (p<0.05). Except for 10% DFF group, Firmicutes of all treatment were higher than that of control group. The Bacteroides of each treatment group were lower than that of the control group (p>0.05). At the same time, the nutrient apparent metabolic rate and cecal microbial abundance of each treatment group had an increasing trend (p>0.05). Conclusion: In conclusion, the feed fermented by enzyme and bacteria had a potential promoting effect on the growth performance and nutrient digestibility of broilers.

• 한국축산식품학회지
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• 제44권4호
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• pp.805-816
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• 2024

The aim of this study was to evaluate a new Bacillus amyloliquefaciens B-1895 probiotic as a feed additive for farmed trout. Final weight, absolute and average daily gain of fish, and average daily growth rate were higher in the group that received the probiotic than in the control group (p<0.05). Moreover, the probiotic-fed trout had more intense growth rates than the control group (higher by 15.7%; p<0.05). A decrease in feed ratio was also observed in the group that received probiotic (25% decrease; p<0.05), indicating more efficient digestion and assimilation of feed. In general, the introduction of probiotic in the feed did not adversely affect the functional status of the fish. In young trout of the control group, when assessing the general chemical composition of the organism in the muscle tissue revealed significantly (p≤0.001) higher level of moisture content by 5.1% and lower by 11.0% dry matter content. In muscle, the protein content was higher by 1.33% (p≤0.001) and fat content by 2.1% (p≤0.001) in experimental fish. Generally, Lactobacilli, Enterococcus, Vibrio, Bacillus, and coliform bacteria were found in the intestinal samples of rainbow trout. Significant reliable difference (p≤0.05) between the samples of experimental and control groups was noted in the content of Bacillus bacteria. In the control group, 5.0±0.4×10³ CFU/g was detected, while in the experimental group 8.4±0.8×10⁴ CFU/g. Overall, the data indicate that probiotic bacteria B. amyloliquefaciens B-1895 has no adverse effect on selected microorganisms in the study fish.

• Asian-Australasian Journal of Animal Sciences
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• 제11권2호
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• pp.176-184
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• 1998

A total of 125 pigs (5.8 kg of BW) were allotted in a completely randomized block design. Treatments were coconut oil, corn oil, soybean oil, tallow and tallow+lecithin. Each treatment had 5 replicates with 5 pigs per replicate. From d 0 to 7, pigs fed vegetable oil supported greater average daily gain (ADG) and improved feed/gain (F/G) compared to pigs fed the animal fat. Addition of lecithin to tallow increased ADG by 7.2%. Feed intake were similar for all treatment groups. From d 8 to 14, pigs fed coconut oil and soy oil showed better ADG and average daily feed intake (ADFI) than any of the others. From d 15 to 21, pigs fed the tallow diets had lower gains (p < 0.05) than those fed diets that contained vegetable oil and tallow with added lecithin. The effect of different fat sources on gain became smaller with age. Feed intakes were similar between the vegetable oil and lecithin supplemented diets each week postweaning except for pigs fed tallow (p < 0.05). Feed : gain ratios were superior during the initial 2 weeks postweaning period when pigs were provided vegetable oil diet compared with pigs fed tallow. All pig groups had similar feed : gain ratios during 3 weeks. Combinations of tallow with lecithin tended to have intermediate feed/gain ratio. It was found that vegetable oils were much better in improving growth rate of the piglets. Lecithin significantly improved growth rate and feed efficiency of the pigs through the whole experimental period compared to tallow. Coconut oil was the most effective in improving growth of pigs during the first two weeks postweaning. Corn oil had equal value with soy oil in improving growth performance of weaned pigs. When vegetable oil was added, the digestibilities of nutrients except for minerals were higher than when the tallow was fed. Nutrients digestibility was similar among vegetable oils. The addition of lecithin to tallow increased digestibility of gross energy, dry matter, ether extract and crude protein. Crude ash and phosphorus digestibility were not affected by the treatments. Dry matter excretion was not different among treatments except for tallow which showed significantly higher dry matter excretion (p < 0.05), while nitrogen excretion was significantly decreased in pigs fed vegetable oil sources. However, Phosphorus excretion was not affected by the different fat sources.

• 생물환경조절학회지
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• 제20권1호
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• pp.8-13
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• 2011

본 연구는 피복재 종류에 따른 착색단고추의 생육 및 생산성에 대한 지하부 환경 요인의 영향 정도를 알아보았다. 조사 기간 동안 배양액 공급량은 플라스틱 필름온실에서는 $5,404L{\cdot}m^{-2}$로 유리온실의 $3,483L{\cdot}m^{-2}$보다 1.6배나 많았다. 그러나 배양액 흡수율은 두 온실에서 71.3~73.3%로 유사한 수준이었다. 배지 EC도 $4.17{\sim}4.23dS{\cdot}m^{-1}$ 수준으로 큰 차이를 나타내지 않았다. 정단부에서 아래로 6번째 잎의 면적은 유리온실에서 평균 $123.0cm^2$/1eaf로 플라스틱필름온실의 $119.5cm^2$/1eaf보다 다소 넓었다. 그러나 잎의 생체중, 건물중 및 건물률은 두 온실 간 뚜렷한 차이를 나타내지 않았다. 주간 생산량은 유리온실에서 $850g{\cdot}m^{-2}$로 플라스틱필름온실의 $650g{\cdot}m^{-2}$보다 1.3배정도로 많았다. 하지만 조사 기간 동안 잎의 면적 및 건물률, 그리고 생산량 모두에 대한 배지 EC와 배양액 흡수율 차이에서 오는 영향은 두 온실 간 뚜렷한 차이를 나타내지 않았다. 따라서 피복재 및 지상부 환경이 다른 온실에서 착색단고추 수경재배 시 생육 및 생산성 차이에 대한 지하부 요인의 영향은 거의 없는 것으로 판단된다.