• Parasites, Hosts and Diseases
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• v.60 no.5
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• pp.345-352
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• 2022

Chitinase AO-801 is a hydrolase secreted by Arthrobotrys oligospora during nematode feeding, while its role remained elusive. This study analyzed the molecular characteristics of recombinant chitinase of Arthrobotrys oligospora (reAO-801). AO-801 belongs to the typical glycoside hydrolase 18 family with conserved chitinase sequence and tertiary structure of (α/β)₈ triose-phosphate isomerase (TIM) barrel. The molecular weight of reAO-801 was 42 kDa. reAO-801 effectively degraded colloidal and powdered chitin, egg lysate, and stage I larval lysate of Caenorhabditis elegans. The activity of reAO-801 reached its peak at 40℃ and pH values between 4-7. Enzyme activity was inhibited by Zn2⁺, Ca2⁺, and Fe3⁺, whereas Mg2⁺ and K⁺ potentiated its activity. In addition, urea, sodium dodecyl sulfate, and 2-mercaptoethanol significantly inhibited enzyme activity. reAO-801 showed complete nematicidal activity against C. elegans stage I larvae. reAO-801 broke down the C. elegans egg shells, causing them to die or die prematurely by hatching the eggs. It also invoked degradation of Haemonchus contortus eggs, resulting in apparent changes in the morphological structure. This study demonstrated the cytotoxic effect of reAO-801, which laid the foundation for further dissecting the mechanism of nematode infestation by A. oligospora.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.291-298
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• 2008

For many years beak trimming has been a controversial subject, particularly since the 1980's when the practice came under close scrutiny by animal welfare groups. In Australia it is considered an essential practice, averting losses of AUD$17.5m annually by reducing mortality from cannibalism. While mortality in flocks from cannibalism can be reduced from 25% of the flock to virtually nil, the beak trimming procedure is considered traumatic for the bird. This study examined if chronic pain in the beak was evident in birds 10, 20 and 60 weeks after being trimmed at hatch and in another group of birds, 8 and 52 weeks after being re-trimmed at 14 weeks. Chronic pain was assessed by measuring pecking behaviour and beak sensitivity responses. Pecking behaviour studies completed after beak trimming and re-trimming showed no evidence to indicate that birds were suffering severe chronic pain in the beak. Beak trimmed pullets pecked more at the cage and had more toe pecks, yet overall pecks made at the feed and the environment were no different than untrimmed controls. While the beak sensitivity studies provided evidence that the beak of birds trimmed at hatch and also re-trimmed at 14 weeks may be more sensitive there was no evidence that re-trimming resulted in a more sensitive beak than birds trimmed at hatch only. These studies have shown that birds which are beak trimmed and re-trimmed return to apparently normal feeding and pecking behaviour in the long term. However, there was limited evidence that beaks of trimmed birds have an altered threshold to potentially painful stimuli.

• 모자간호학회지
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• v.3 no.2
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• pp.172-186
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• 1993

The survey was performed on 201 cases of mothers who visited pediatric hospitals and public health clinics in Pusan and Kyeong-nam provinces from Dec. 10 to Dec. 30 of 1993. If this study, each infant weighed over 2500gm and between 2 months and 12 months old. The research was statistically analyzed according to the percentage, Pearson correlation, $x^2$-test. The result of this study were as follows ; 1. Feeding method related to the job of mother (p<0.01). 2. Feeding method related to the way of bringing up child(p<0.05). 3. Whether the mother and child shared the same room effected the feeding method (p<0.01). 4. The shape of nipple before breast feeding related to feeding method. 5. The reason for stopping breast feeding related to feeding method(p<0.01). 6. First breast feeding related to period of seperation after delivery(p<0.05). 7. Plan of breast feeding related to birth weight (p<0.05).

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.313-317
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• 2005

The facility improvement for hot firing test of combustion chamber having thrust of 30-tonf class and chamber pressure of 60bara were performed at ReTF in KARI. The KSR-III main engine having combustion pressure of 13bara and thrust of 12.5tonf had been successfully tested in this facility. To increase the capability of the facility, the feeding and the trust measurement system have been modified. The modification of the feeding system plays also a role of ensuring the stability of propellant supply and two step ignition sequence of combustion chamber. The one-axis thrust measurement system of up to 60tons has been newly manufactured and installed in test stand and the water/kerosene supply lines with high pressure vessel of $4m^3$ and gas nitrogen vessel of $10m^3$ have been designed for regenerative cooling system. The results of cold flow test show that this facility has been successfully improved to satisfy the requirement for hot firing test of high performance combustor.

• Korean Journal of Poultry Science
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• v.34 no.1
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• pp.23-29
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• 2007

Rare earth(RE) is a common name indicating 17 of specific elements including 15 of lanthanides, scandium (Sc), and yttrium(Y). This study was conducted to compare the effect of RE to growth stimulating antibiotic products in broiler diet. One of the products commonly used in broiler feeding, Chlorotetracycline(CTC) was used at a level of 200ppm for the antibiotic treatment and replaced by 100ppm RE for the RE treatment. Dietary addition of RE and CTC showed similar effects in improving broiler growth and feed conversion each other, and those were significantly better when compared to those of the control group(P<0.05). Abdominal fats of chicks fed RE were significantly lower than others(P<0.05). Intestinal E. coli and total microbial numbers were reduced by RE addition(P<0.05), but the number of Lactobacillus was not affected. The number of Salmonella was also decreased but it was not significant.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.75-79
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• 1992

Fourteen Sahiwal ${\times}$ Friesian crossbred heifers were used in a 10-wk feeding trial to determine maintenance energy requirements and efficiency of gain. The heifers were individually fed with a diet consisting of 30% dry grass and 70% concentrates at either 110, 140 or 180% of the anticipated maintenance requirement ($494kJ\;ME/kg^{0.75}/day$). Liveweight of individual heifers was measured weekly to calculate diet requirements and average daily gain (ADG). Diet digestibility was determined for all heifers to determine ME intake. Retained energy (RE) of individual heifers was determined from changes in total body fat and protein using a TOH isotope dilution procedure and, assuming calorific values of 39.3 and 23.6 kJ/g for fat and protein respectively. The estimated ME for maintenance was 433 and $470kJ/kg^{0.75}/day$ by liveweight (ADG) equilibrium and energy (RE) equilibrium analysis respectively. ME requirement for one g of liveight gain was 28 kJ.

• Korean Journal of Ichthyology
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• v.29 no.3
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• pp.165-175
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• 2017

To minimize the damage caused by summer season such as high temperature and red tide, this study was conducted to investigate the effect of feeding and starvation on the survival rate, growth, growth restoration and physiological response of red seabream Pagrus major which were reared in marine net cage ($6m{\times}6m{\times}6m$). The feeding group was fed throughout the experiment for 10 weeks, whereas starvation group was not fed for 6 weeks and subsequent refeeding for 4 weeks. Survival rates of feeding and starvation groups were 94.4% and 98.1% respectively. The growth rate of starvation group was significantly lower than feeding group during starvation period, but recovered rapidly after feeding. The nutritional status such as albumin, total protein, total cholesterol, triglyceride also showed similar tendency to the growth data. Hematocrit and hemoglobin levels were higher in the feeding group than the starvation group during starvation period. Aspartate aminotransferase, glucose and total cholesterol were rapidly increased at the same time (in 5 week) in feeding group, whereas starvation group did not significant difference during starvation period. It was shown that the feeding group is more sensitive to stress than the starvation group. Thus, starvation can be applied as a rearing management plan of net cage fish farm in summer season.

• Journal of Animal Science and Technology
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• v.50 no.4
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• pp.485-498
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• 2008

This study was conducted to evaluate effects of dietary rare earth on growth performance, blood immune- related cell population, meat quality and fecal odor emitting gases in finishing pigs. The total of sixty four (Landrace×Yorkshire×Duroc) pigs(65.42±1.16kg in average initial body weight) were used for feeding trial during 10 weeks of experimental period. Dietary treatments included 1) NC(antibiotic free diet), 2) PC (NC diet+6 weeks 44ppm of tylosin/ 4 weeks 22ppm of tylosin) 3) RE1 (NC diet + 100ppm of RE), 4) RE2 (NC diet+200ppm of RE). There were four dietary treatments with four replicate pens per treatment and four pigs per pen. During the overall periods, there were no significant differences in ADG(Average daily gain), ADFI (Average daily feed intake) and gain/feed ratio among treatments(P>0.05). Dry matter and nitrogen digestibility were higher in RE2 treatment group than other groups(P<0.05). Also, energy digestibility was higher in RE2 treatment group than PC and RE1 treatment groups(P<0.05). At the 6th week WBC(white blood cell) was significantly increased(P<0.05) in RE1 treatment group than NC and RE2 treatment groups. L* value of M. logissimus dorsi muscle color was significantly increased(P<0.05) in rare earth supplemented groups compared to NC treatment group(P<0.05). However, a* value was lower in RE1 treatment group than PC treatment group (P<0.05). In fatty acid composition of Intramuscular fat, total MUFA was significantly higher in RE2 treatment group than other groups(P<0.05). Also, total UFA was significantly increased in RE2 treatment group compared with NC and PC treatment groups(P<0.05). In fatty acid composition of back fats, total SFA of rare earth supplemented groups were lower than in PC treatment group(P<0.05). UFA:SFA ratio was significantly higher in rare earth supplemented groups than PC treatment group(P<0.05). In fecal odor emission, NH3 was significantly decreased(P<0.05) in rare earth supplemented groups compared to NC and PC treatment groups. In conclusion, the results of the experiment was affected by rare earth supplementation on digestibilities, meat quality, fatty acid and fecal odor emission gases in finishing pigs.

• Journal of Nutrition and Health
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• v.34 no.5
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• pp.547-553
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• 2001

This study was designed to observe the change of body composition and nutrient metabolites and the excretion of minerals during complete fasting for 10 days in thirty women. Average loss of body weight was 7.98kg and body fat was gradually reduced after 9 days fasting, but the loss of lean body mass was reduced after 7 days fasting. Serum glucose level was sustained at constant level, but serum levels of blood urea nitrogen, free acid and $\beta$-hydroxybutyrate were significantly increased during fasting but decreased after re-feeding. Urinary excretions of 3-methylhistidine, total creatinine, and urea were high in the beginning of fasting but gradually decreased. Serum level of parathyroid hormone was significantly reduced by fasting but regained after re-feeding. Serum level of minerals was at the constant level throughout the experimental period. The urinary excretion of minerals(Ca, K, Mg, P) was significantly increased in the early stage of fasting and then reduced from 7 days, but the excretion of Zn was continuously increased until the late stage of fasting. These results showed that amino acid fatty acid released from the breakdown of muscle protein and body fat, respectively, were utilized for energy during fasting. Body weight and BMI were reduced because of the increased muscle protein breakdown and body water excretion during early stage of fasting, but the significant body fat loss was after 9 days fasting. Therefore, it could be suggested to fast for longer than 10 days if the reduction of body fat was planned by fasting, and recommed to exercise and ingest more vitamins and minerals to replace the excreted minerals during fasting. (Korean J Nutrition 34(5) : 547~553, 2001)

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.99-99
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• 2002

The hormone resistin is associated with typeII diabetes mellitus in rodent model. Resistin impairs glucose tolerance and insulin action. A new class of anti-diabetic drugs were called thiazolidinediones (TZDs) downregulates a resistin which is induced during adipocyte differentiation. But the connection between increased adiposity and resistin remains unknown. The objectives of this study was to clone a mouse resistin cDNA and to generate transgenic mice overexpressing mouse resistin gene. The 555 bp of mouse resistin was amplified from mob cDNAS by polymerase chain reaction (PCR) and cloned into pCR$\^$(R)/ 2.1 TOPO T-vector. Mouse resistin mRNA on the basis of Genbank sequence (acession no. AF323080). Then, the PCR product was cloned into pTargeT$\^$TM/ mammalian expression vector that has pCMV promoter and chimeric intron. Restriction enzyme analysis with BamH I and Not I was carried out to determine an orientation of the insert in the vector. The pCMV-mus/resistin gene was prepared from previous recombinant pTargeT$\^$TM/-mus/resistin by digestion of Bgl II, and has used for microinjection into pronuclei of one cell embryos. The microinjected embryos were transfered to pseudopregnant foster-mother. Mouse resistin expression was detected in transgenic F1 mice by Reverse Transcriptase- Polymerase Chain Reaction (RT-PCR). Resistin gene expression mouse has heavier body weight which was measured higher level of plasma glucose than that of normal mouse. And in diet-induced experiments, the abdominal fat pads were isolated from each 24h starvation and re-feeding after fasting group mice that were assessed by RT-PCR analysis. In fasting group mice, resistin expression was higher than that of re-feeding group mice. This result suggests that the resistin gene overexpressing mice may be became to obesity and be useful as an animal disease model to be diabetes mellitus caused by insulin resistance of resistin.