• Korean Journal of Poultry Science
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• v.15 no.3
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• pp.229-246
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• 1988

These studies were conducted to investigate the effects of dietary protein and metabolizable energy(ME) levels on layer performance during summer period. Total 480 ISA Brown egg-type layers ageing 49 weeks housed 2 birds per cage with 4 replictes of 20 birds were employed in this study. Mean environmental temperature over experimental period ranged from 22.3$^{\circ}$to 29.5$^{\circ}C$. The treatments consisted of dietary ME levels of 2500, 2700, 2900kcal/kg of diet containing 15% and 17% protein, respectively, to provide $3{\times}2$factorial design. As metabolizable energy level increased form 2500 to 2900 kcal/kg of diet, daily feed and protein intake, egg production. egg weight, egg mass decreased, but the reverse was true for the daily energy intake, energy requirement and feed costs per kg egg. Feed conversion(kg feed/kg egg) and viability were not affected by the dietary energy levels. However, there were no significant difference in egg production, protein requirement per kg egg, and egg weight between those hens fed 2500 kcal ME/kg diets and those fed 2700 kcal ME/kg diets, and no difference was found in egg weight between those fed 2700 kcal ME/kg and those fed 2900 kcal ME/kg, either. In addition, no specific trend was observed in protein requirement per egg by the different level of metabolizable energy in diets. On the other hand, as dietary protein level increased from 15 to 17%, daily protein in-take, egg production, egg weight, egg mass, and protein requirement and feed costs per kg egg increased, but feed and energy requirement per kg egg decreased, and no significant difference in the daily feed and energy intake and viability were observed among dietary protein levels. It was concluded that metabolizable energy level of 2500 kcal/kg of diet and 17% dietary protein level were considered to be adequate to support the optimum productivity of layers during summer period.

• Journal of the Korean Applied Science and Technology
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• v.31 no.2
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• pp.255-264
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• 2014

This study was performed to elucidate the biochemical mechanism of metabolism on reducing blood lipid, by oral administration of egg yolk in rats. A total of 36 Sprague Dawley male rats were randomized into four treatment groups, according to a randomized block design. Each group was further divided into three repeat cages, with each repeat cage comprising of 3 rats. The animals were orally administered with egg yolk once a day, while feeding the same purified pellet diet for 6 weeks. The four treatment groups were: C(control, saline 1.0 g), T1(pork belly oil 1.0 g), T2(egg yolk 1.0 g), T3(pork belly oil 1.0 g and egg yolk 1.0 g alternating every week). The measured parameters in each group are listed as follows in the order of highest to the lowest: daily average gain of body weight(T1>T3>T2>C); blood triglyceride and total cholesterol(T1>C>T3>T2) HDL-C (T2>C>T3>T1); and LDL-C (T1>T3>C>T2). AST and ALT, which are the index of liver function, were the highest in T1 but was lowest in T2. The weights of the liver, spleen, and kidney, except for the abdominal fat, showed no significant difference. The weight of abdominal fat was the highest in T1, but there were no significant difference among C, T2, and T3. The HMG-CoA reductase activity was the highest in T1 followed by T3, C but T2 was lowest. The daily fecal excretions of the total sterol, neutral sterol and acid sterol was highest in T2 but lowest in T1. The results of this study show that the egg consumption reduces the blood lipid through facilitation of fecal excretions of sterols and inhibition of enzyme activity in cholesterol biosynthesis, in the liver of animal and human.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.547-554
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• 2005

An experiment was conducted to investigate the dietary effects of a transgenic Aspergillus oryzae(AO) culture on the performance, egg quality and intestinal microflora of layers. A total of 840 Hy-line Brown layers of 39wks old were assigned to one of the following 7 dietary treatments: control(C), C+0.2% AO culture, C+0.5% AO culture, C+0.2% transgenic AO culture, C+0.5% transgenic AO culture, C+0.2% transgenic mutant AO culture, and C+0.5% transgenic mutant AO culture. The transgenic AO was made by inserting Salmonella gallinarum gene to AO. And the transgenic mutant AO was made by inserting Salmonella gallinarum gene to mutant AO which was mutated by UV irradiation. Each treatment was replicated six times with 20 birds housed in 2 bird cage. Twenty birds units were arranged according to completely randomized block design. Feeding trial lasted for 8wks under 16 hour lighting regimen. Laying performance and egg quality were significantly(P<0.05) affected by the treatments. Transgenic AO culture supplementation at the level of 0.2% significantly increased egg production, while its egg weight was significantly decreased compared to that of the control. Feed intake and feed conversion ratio(FCR) were not significantly different among the AO treatments and the control. The eggshell strength of the AO treatments was significantly higher than that of the control. Transgenic mutant AO culture supplemented at the level of 0.5% significantly increased egg yolk color. Intestinal microflora were significantly(P<0.05) affected by the treatments. The cfu of Lactobacilli spp. significantly increased and those of Salmonella species and E. coli decreased in the AO treatments. The transgenic AO and transgenic mutant AO culture were more effective than the AO culture in reducing the cfu of Salmonella species and E. coli. It is concluded that supplementation of the transgenic AO culture at the level of 0.2% could be recommended for the improvement of egg production. Supplementation of transgenic AO or transgenic mutant AO culture at 0.2% level effectively controlled intestinal Salmonella species population.

• Korean Journal of Poultry Science
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• v.37 no.1
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• pp.51-62
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• 2010

This study was conducted to investigate the effects of dietary supplementation of multiple probiotics on the performance, small intestinal microflora and immune response in laying hens and broilers. In Exp.1, a total of 800, 82 wk old Hy-line Brown$^{(R)}$ laying hens were assigned to one of the following five dietary treatment; Control, Antibiotics (avilamycin 6 ppm), Probiotics; PB-M (Micro-ferm$^{(R)}$ 0.2%), PB-L (Lacto-sacc$^{(R)}$ 0.1%), PB-Y (Y University probiotics 0.2%). Each treatment was replicated eight times with 20 birds in each replicate and two birds were housed in each cage. Twenty birds units were arranged according to completely randomized block design. Feeding trial lasted 6 wk under 16 h lighting regimen. The Exp. 2, was conducted with a total of 1,000 broilers chicks (Ross$^{(R)}$). They were divided into five treatments, same as those of Exp. 1. Birds were fed starter (0~3 wk) and grower (4~5 wk) diets. Each treatment was replicated four times with 50 birds per pen comprising of deep litter. In Exp. 1, egg production parameters, such as hen-day and hen-house egg production, egg weight, broken and soft shell egg production, feed intake and feed conversion were not significantly different among treatments. However, strength and thickness of eggshell were significantly (P<0.05) different. Among the probiotics, PB-Y showed the highest strength and thickness of eggshell. Eggshell color, egg yolk color and Haugh unit were not significantly influenced. In Exp. 2, overall weight gain (0~5 wk) and mortality were not significantly different among treatments. However, weight gain of birds from PB-Y treatment during starter (0~3 wk) was significantly lower than the birds from Control and Antibiotic treatment. During the whole period (0~5 wk), birds from Antibiotics treatment had higher feed intake and Production Index (PI) and lower feed conversion than birds from Control treatment. Probiotics treatments were not significantly different from the Control on feed intake and feed conversion. In Exp.1, there were significant (P<0.05) differences in leukocytes parameters, such as white blood cell (WBC), hetrophil (HE), lymphocytes (LY), monocyte (MO), eosinophil (EO) and stress index (SI; HE/LY) in the blood of layers. Birds from Antibiotics and probiotics treatments tended to increase these parameters. In Exp. 2, however, only SI was significantly (P<0.05) decreased in Antibiotics treatments. Concentration of serum immunoglobulin (IgG) were higher (P<0.05) in PB-M and PB-Y treatments when compared with Control treatment in Exp. 1. The population of E. coli significantly (P<0.05) decreased in birds from Antibiotics, PB-L and PB-Y treatments when compared with birds from Control treatment in Exp. 1. Metalbolizability of crude fat decreased significantly (P<0.05) in birds from probiotic treatments in Exp. 2. It was concluded that the response of probiotics on the productivity of layers and broilers were different. Probiotics increased strength and thickness of eggshell in layers, and decreased feed conversion and increased PI in broilers. Leukocytes and IgG tended to increase by supplementation of antibiotics and probiotics in layers. Intestinal E. coli tended to decrease in layers. Digestibility of crude fat of diet decreased in probiotics treatments broilers. Parameters of blood and microbial were more sensitive in layers than broilers.

• Korean Journal of Poultry Science
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• v.35 no.2
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• pp.143-151
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• 2008

This study was conducted to identify the correlation of bacterial phytase ($Transphos^{(R)}$) to the calcium level in feed. Of all 21-week-old 720 HyLine brown laying hens, 2 birds of similar weight were placed on each individual cage. The experiment was conducted by $3{\times}2{\times}3$ factorial design with including 3 different levels of phytase (0, 300, and 1,000 DPU/kg), 2 different levels of calcium (3.5% and 4.0%), and 3 different levels of no NPP addition 0% (0.095 NPP), 0.5% (0.185% NPP), and 1.0% (0.275% NPP). The feeding trial maintained the ME level of 2,800 kcal/kg and 16% for crude protein. The diet was fed ad libitum and 17 hours of lighting was provided throughout the experimental period. Egg production seemed to increase, in the 300 DPU of bacterial phytase added group and the cracked egg tended to reduce in Transphos added group. The egg productivity between treatment groups did not show significant difference by dietary calcium level, whereas non NPP added group (0.095% NPP) was found to be low compared to NPP added groups (P<0.05). The highest mean egg weight and the highest daily egg mass were detected in 300 DPU phytase added group. Although the mean egg weight was significantly higher in treatment groups fed with 3.5% calcium containing feeds (P<0.05), daily egg mass was no among treatment groups. The mean egg weight and daily egg mass were the lowest in non NPP added group (0.095% NPP) compared to other treatment groups (P<0.05). The feed intake showed similar pattern regardless of the bacterial phytase and calcium levels in the diet. However, the treatment groups fed diets containing NPP level of 0.275% and 0.165% showed significantly higher feed intake than the group fed with 0.095% NPP (P<0.05). Although the feed conversion was not affected by calcium and NPP levels in the diet, the most improved result was obtained from 300 DPU phytase added group (P<0.05). The eggshell breaking strength and thickness increased as dietary calcium level increase the level of calcium increases in diet. The treatment groups fed diet containing 0.275% and 0.165% NPP revealed to show improvement in eggshell breaking strength and yolk color index compared to the NPP non added (0.095% NPP) treatment group. The result of the present study suggests that the appropriate level of microbial phytase is 300 DPU and at this level, tricalciumphosphate supplementation in feed can be reduced to 40% of NRC recommendation. Higher calcium level in feed fail to show synergistic effect by adding microbial phytase.