• Korean Journal of Poultry Science
• /
• v.16 no.4
• /
• pp.193-199
• /
• 1989

This study was conducted to estimate heritabilities and genetic correlations on egg compositions in Korean Native Ogol Fowl. The date analysis were a total of 58,320 eggs in 450 pullets producted from 150 dams and 20 sires of Korean Native Ogol Fowl raised at Chungnam National University from June 18. 1987 to April 6. 1989. The results obtained are summarized as follows： 1. On the egg compositions, the albumen weight at first egg, 300 and 500 days were $24.003\pm$2.499, $28.354\pm$2.755 and $31.863\pm$3.341g； the yolk weight were $10.272\pm$1.536, $16.346\pm$1.321 and $19.212\pm$1.661g： the shell weight were $3.906\pm$0.414, $4.336\pm$0.506 and $4.822\pm$0.515g, respectively. 2. The heritability estimates of egg compositions based on the valiance of sires, dams and combined components were 0.620-0.723, 0.206-0.300 and 0.413-0.511 for albumin weight；0.439-0.737, 0.484-0.544 and 0.492-0.615 for yolk weight：0.172-0.187, 0.412-0.642 and 0.390-0.503 for shell weight, respectively. 1. The genetic and phenotypic correlation coefficients of egg compositions were as follows； The coefficients between albumen weight and yolk weight were 0.089-0.654 and 0.084-0.255；between albumen weight and shell weight were 0.396-0.925 and 0.225-0.544； between yolk weight and shell weight were 0.227-0.357 and 0.098-0.358 respectively.

• Korean Journal of Poultry Science
• /
• v.29 no.2
• /
• pp.81-88
• /
• 2002

The objective of this study was to investigate the line-by-feed additive interaction on egg traits and yolk cholesterol level in laying hens. Hy-line W-98 (white shell line) and Hy-line Brown (brown shell line) were used as experimental stocks and three groups were assigned in each line. The age of hens used in this study were from 40- to 46-wk-old. Two different levels of chitosan were also used as additive in chicken diet. The first (CH$_{30}$) and second (CH$_{60}$) experimental groups were fed basal diet added 30mg and 60mg chitosan/kg feed, respectively. And the control group (CON) hens were fed with basal diet only. The eggs were collected and analyzed at the end of 40, 42, 44, and 46-wk-old. In the mean egg weight, the CH$_{30}$ in Hy-line Brown was significantly heavier (P<0.05) than CON, but the CH$_{30}$ in Hy-line W-98 was significantly lighter (P<0.05) than CON. Whereas, the mean egg weight did not significantly differ between CH$_{60}$ and CON in both line. The mean albumen percentage in Hy-line Brown did not show significant between experimental groups and control group. On the other hand, the mean albumen percentage of CH$_{60}$ in Hy-line W-98 was significantly lower (P < 0.05) than that of CON, but there was no significantly different between CH$_{30}$ and CON. In the mean yolk percentage, it showed a reverse trend as shown in the mean albumen percentage; there were significantly higher (P<0.05) in CH$_{60}$ than in CON fur the Hy-line W-98, and higher in CH$_{30}$ than in CON for the Hy-line Brown. However, the mean shell percentages did not significantly differ between experimental groups and control group in both lines. In the mean yolk cholesterol levels, the CH$_{30}$ and CH$_{60}$ in both lines were lower by 0.46 mg ∼2.80 mg per gram yolk than CON. Although the interaction effect of line-by-supplementing level of chitosan in hens diet on the pooled mean of yolk cholesterol level was no significant, it showed a highly significant interaction (P<0.01) at three of four experimental ages.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.2
• /
• pp.206-210
• /
• 2017

Objective: A study was conducted to test six threonine (Thr) levels (0.39%, 0.44%, 0.49%, 0.54%, 0.59%, and 0.64%) to estimate the optimal dietary Thr requirements for Longyan laying ducks from 17 to 45 wk of age. Methods: Nine hundred Longyan ducks aged 17 wk were assigned randomly to the six dietary treatments, where each treatment comprised six replicate pens with 25 ducks per pen. Results: Increasing the Thr level enhanced egg production, egg weight, egg mass, and the feed conversion ratio (FCR) (linearly or quadratically; p<0.05). The Haugh unit score, yolk color, albumen height, and the weight, percentage, thickness, and breaking strength of the eggshell did not response to increases in the Thr levels, but the albumen weight and its proportion increased significantly (p<0.05), whereas the yolk weight and its proportion decreased significantly as the Thr levels increased. Conclusion: According to a regression model, the optimal Thr requirement for egg production, egg mass, and FCR in Longyan ducks is 0.57%, while 0.58% is the optimal level for egg weight from 17 to 45 wk of age.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.7
• /
• pp.841-846
• /
• 2008

In this study, the effects of feeding citrus byproducts on nutritional properties of Korean native chicken eggs were investigated. Two samples of Korean native chicken eggs were used for this study: T0 (Eggs of chickens that were not fed with citrus byproducts until they became 30 weeks old) and T1 (Eggs of chickens that were fed with 4% citrus byproducts when they were between 17 and 30 weeks old). There was nostatistically meaningful difference between T0 and T1 in terms of various properties, such as general components of egg albumen and yolk, total structural amino acid, and total free amino acid. Also, no significant difference was noticed between T0 and T1 in terms of various components of egg yolk, such as amount of mineral, vitamin, and xanthophyll, which showed that those components are not affected by citrus byproducts. However, the amount of cholesterol of egg yolk for T1 was 1,168 mg/100 g, which was significantly lower than that for T0 which was 1,207 mg/100 g (p<0.05). The amount of L-glutamic acid, one of the free amino acids, of the egg albumen was 39.22 and 58.54 ppm for T0 and T1, respectively. The results of this study show that citrus byproducts can be used for the feed for Korean native chicken by adding them to general feed.

• Applied Biological Chemistry
• /
• v.43 no.4
• /
• pp.260-265
• /
• 2000

To determine the quality change of the irradiated eggs during storage, fresh shell eggs were irradiated using $^{60}Co$ at 0, 1, 5, 10, 30 kGy and stored for 30 days. The york index, color, pH, viscosity, egg weight, and SDS-PAGE profile of the irradiated eggs were examined. During storage, york index values of the irradiated eggs and the control were decreased and the increase of dose decreased yolk index. However, the yolk index values were increased temporarily at 10 kGy and 30 kGy. The yolk color had a bright yellow with increases in dose level and there was no significant change during storage. The albumen viscosities were decreased with increases in dosage and were decreased during storage. Also, the albumen pH values of the irradiated eggs were higher than that of the control and were increased during storage. The weight losses of eggs were increased during storage and there were no significant changes by dose level. SDS-PAGE profile of the egg white proteins of the shell eggs showed the change in molecular weight distribution and had aggregation pattern as well as degradation. CD and fluorescence spectroscopy study showed changes in the secondary and tertiary structure of egg white proteins by ${\gamma}-irradiation$. Therefore, this study clearly indicates that irradiation dose of eggs should be appropriate to prevent the loss of egg qualities.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.3
• /
• pp.400-409
• /
• 2017

Objective: This study was conducted to evaluate the effects of dietary protein sources (soybean meal, SBM; low-gossypol cottonseed meal, LCSM; double-zero rapeseed meal, DRM) on laying performance, egg quality, and plasma parameters of laying hens. Methods: A total of 432 32-wk-old laying hens were randomly divided into 6 treatments with 6 replicates of 12 birds each. The birds were fed diets containing SBM, $LCSM_{100}$, or $DRM_{100}$ individually or in combination with an equal amount of crude protein (CP) ($LCSM_{50}$, $DRM_{50}$, and $LCSM_{50}-DRM_{50}$). The experimental diets, which were isocaloric (metabolizable energy, 11.11 MJ/kg) and isonitrogenous (CP, 16.5%), had similar digestible amino acid profile. The feeding trial lasted 12 weeks. Results: The daily egg mass was decreased in the $LCSM_{100}$ and $LCSM_{50}-DRM_{50}$ groups (p<0.05) in weeks 41 to 44. The $LCSM_{50}$ group did not affect egg production compared to the SBM group in weeks 41 to 44 (p>0.05) and showed increased yolk color at the end of the trial (p<0.05). Compared to the SBM group, the $LCSM_{100}$ and $LCSM_{50}-DRM_{50}$ groups showed decreased albumen weight (p<0.05), CP weight in the albumen (p<0.05) and CP weight in the whole egg (p<0.05) at 44 weeks. Plasma total protein (TP) levels were lower in the $LCSM_{100}$ group than in the SBM group at 44 weeks (p<0.05); however, TP, albumin, and globulin levels were not significantly different between the $LCSM_{50}$ group and the SBM group or between the $DRM_{50}$ group and the SBM group (p>0.05). Conclusion: Together, our results suggest that the $LCSM_{100}$ or $DRM_{100}$ diets may produce the adverse effects on laying performance and egg quality after feeding for 8 more weeks. The 100.0 g/kg LCSM diet or the 148.7 g/kg DRM diet has no adverse effects on laying performance and egg quality.

• Journal of Animal Science and Technology
• /
• v.55 no.2
• /
• pp.115-122
• /
• 2013

This study was conducted to evaluate the effect of dietary ${\beta}$-mannanase supplementation and palm kernel meal (PKM) inclusion (5%) on laying performance, egg quality and nutrient utilizability of laying hens with 73 weeks of age. A total of 240 Lohmann brown laying hens with average 77.5% egg production were randomly allocated with 60 hens per treatment, 4 replicates per treatment and 15 hens per replicate. Experimental design was a completely randomized design with $2{\times}2$ factorial arrangement, with the factors being (1) two levels of PKM (0 vs. 5%) and (2) with or without dietary ${\beta}$-mannanase (480 IU/kg of diet CTCzyme$^{(R)}$) supplementation. All hens were housed in cages ($35cmW{\times}35cmD{\times}40cmH$) with 2 hens per cage for six weeks feeding trial. Laying performance was recorded daily during feeding trial. Egg quality, nutrients utilizability and blood assays were done at the end of feeding trial. Egg production was improved (P<0.05) by both dietary PKM inclusion and ${\beta}$-mannanase combined supplementation. Either ${\beta}$-mannanase or PKM did not affect feed intakes and feed conversion ratio of all diets. Egg weight of hens fed diet containing 5% of PKM had heavier (P<0.05) eggs compared with hens fed without PKM. Albumen height was improved (P<0.05) by dietary mannanase supplementation. Crude fat utilization of 5% PKM diet was higher than that of no PKM diet regardless of ${\beta}$-mannanase supplementation. Both DM and total carbohydrate utilization were decreased (P<0.05) in hens fed 5% PKM diet. Serum IgG and yolk IgY contents of PKM groups were lower (P<0.05) than those of no PKM groups. This result showed that 5% PKM diet, independent of dietary ${\beta}$-mannanase supplementation, was able to improve egg production. In addition, dietary ${\beta}$-mannanase supplementation could be used for improving the albumen height of eggs.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.10
• /
• pp.1458-1463
• /
• 2016

A 42-d study with 384 Hy-line brown laying hens was conducted to assess the effects of dietary octacosanol supplementation on laying performance, egg quality and blood metabolites of laying hens. Hens were randomly allocated into 4 dietary groups of 8 cages each, which were fed basal diet supplemented with 0 (Control), 9 (OCT9), 18 (OCT18), and 27 (OCT27) mg/kg diet of octacosanol isolated from rice bran, respectively. The experiment was conducted in an environmental controlled house and hens were fed twice daily for ad libitum intake. Laying performance was determined over the 42-d period, and egg quality as well as blood metabolites were estimated on d 21 and d 42. Diets in OCT18 and OCT27 increased (p<0.05) laying rate, egg weight, egg mass, egg albumen height, Haugh unit and eggshell strength on d 42, but decreased (p<0.05) feed conversion rate and levels of total cholesterol, triglyceride and low density lipoprotein cholesterol in the serum as compared to those of Control. Feed intake, yolk color, yolk diameter, eggshell thickness and high density lipoprotein cholesterol were similar (p>0.05) among treatments. Results demonstrate that supplementing 18 to 27 mg/kg diet of rice bran octacosanol can improve laying rate and egg quality and reduce blood lipid of laying hens.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.6
• /
• pp.944-947
• /
• 2007

This study was conducted to study the effects of dietary garlic powder on laying performance, egg traits and blood serum cholesterol level of quails. A total of three hundred quails (Coturnix coturnix japonica) aged nine weeks were used. They were allocated to 3 dietary treatments. Each treatment comprised 5 replicates of 20 quails. The diets were supplemented with 0, 5 and 10 g/kg garlic powder. The experimental period lasted 21 weeks. The addition of garlic powder did not significantly affect body weight, egg production, feed consumption, feed efficiency, egg shell thickness, egg albumen index, egg yolk index and egg Haugh unit. Adding 5 and 10 g/kg garlic powder to the laying quail diets increased egg weight (p<0.01). Egg yolk cholesterol and blood serum cholesterol concentration were reduced with garlic powder supplementation. The results of this study demonstrated that garlic powder addition had a significant cholesterol-reducing effect in serum and egg yolk without adverse effects on performance and egg traits of laying quails.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.11
• /
• pp.1617-1621
• /
• 2002

Two hundred and sixteen single comb white egg layers of the White Leghorn hens of 24 weeks of age were randomly allocated to 12 groups with three replications of six hens in each. Hens were fed in a factorial arrangement 2${\times}3{\times}$2, on diets containing either 16 or 18% crude protein with 0, 3 or 6% fish meal, replacing groundnut meal with soybean meal. Soybean meal incorporation improved (p<0.05) egg production, feed intake, feed conversion efficiency and egg weights. Egg quality traits of specific gravity, shape index, albumen index, yolk index and shell thickness remained unchanged. Laying performance was significantly (p<0.05) better at 18% than on 16% dietary protein level. Use of fish meal linearly improved egg production and feed conversion efficiency on diets supplemented with groundnut meal and fish meal incorporation showed quadratic improvement on feed conversion efficiency with SBM diets at 16% dietary protein level. Therefore, use of soybean meal as substitute of groundnut meal is recommended in layer diets, at 16% dietary protein level and fish meal incorporation could be beneficial for layers.