• 한국가금학회지
• /
• 제27권3호
• /
• pp.243-254
• /
• 2000

The effect of supplemental microbial phytase and non - phytate phosphorus(NPP) levels on layer productivity and nutrient digestibility were conducted in 640 21 weeks - old HyLine brown layer for 12 weeks. Supplemented phytase levels were 0, 300, 500 and 1,000 DPU/kg diet. NPP levels were adjusted with tricalcium phosphate(TCP), which were 0(0.11% NPP), 0.5(0.20), 1.0(0.29) and 1.5%(0.38). ME, CP and Ca levels were maintained at 2,800㎉/kg diet, 16% and 3.5%, respectively. Egg production was increased with phytase compared to without phytase(P〈0.05). Increasement of egg production was higher latter of experimental period. Egg production was not different to phytase levels. Egg production in TCP levels were increased in above 0.5% compared to 0% TCP. Difference of egg production by TCP was higher after 6 week. Especially, egg production to supplemental phytase was higher in 0% TCP. Egg weight was not different to phytase and TCP levels. Egg mass was increased with phytase compared to without phytase, but not difference significantly. There was similar to phytase levels. Egg mass in TCP group was increased in TCP supplementation(P〈0.05). Feed intake was not different in phytase levels, and greater with increasing TCP levels(P〈0.05). Feed conversion was improved with phytase(P〈0.05), and not difference in TCP levels. All of nutrients digestibility tended to improve with phytase, P(P〈0.05), especially. There were not different among phytase levels. The effect of adding phytase was higher in low phosphorus diets compared normal levels. Eggshell breaking strength and eggshell thickness also improved in added phytase(P〈0.05). Tibial ash and P content were slightly increased with phytase, and Ca content also was higher(P〈0.05) compared without phytase. We concluded that supplemental phytase in low phosphorus diet was showed to increase laying performance, feed efficiency, nutrients digestibility, egg quality, and bone development. Phytase supplementation was able to compensate for low NPP diet. We also thought optimum phytase level is 300 DPU, and can decrease NPP supplementation adding phytase in later diet.

• 한국가금학회지
• /
• 제33권1호
• /
• pp.15-24
• /
• 2006

본 연구는 종계사료 내 홍화씨 및 키토산의 첨가 급여가 산란종계에서 종란 생산성 및 후기 난각질 강화에 미치는 영향을 검토하기 위하여 수행하였다. 54주령 Hy-Line Brown 산란종계 암탉 400수와 수탉 40수를 공시하여 Ca을 3.5%로 수준으로 함유한 실험사료(대조구)에 홍화씨 분말을 0.25% 및 0.50% 수준으로 첨가하거나 키토산을 0.10% 및 0.20% 수준으로 첨가한 총 5개의 실험사료(4반복)를 6주간 급여하였다. 사료섭취량 및 난생산성에서는 처리간에 차이가 없었으나, 종란율은 대조구에 비해 홍화씨 분말 및 키토산을 첨가한 모든 실험구에서 첨가 수준과 관계없이 유의하게 증가하였다(P<0.05). 평균 난각 강도는 홍화씨 분말 및 키토산 첨가에 의해 유의하게 개선되었으며(P<0.01), 난각 두께는 키토산 첨가구가 대조구에 비해 유의하게 높은 것으로 나타났다(P<0.01). 수정율 및 입란대 부화율은 대조구에 비해 키토산 첨가구에서 유의하게 개선되는 결과가 관찰되었다. (P<0.01). 경골 파쇄강도는 처리간에 큰 차이가 없었으나, 경골 내 Ca 및 P 함량은 대조구에 비해 홍화씨 분말 0.5% 첨가구와 키토산 첨가구(T3 및 T4)에서 유의하게 증가하였다. (P<0.01). 혈중 estrogen, calcitonin 및 PTH 등 호르몬 농도에서는 큰 변화가 없는 것으로 나타났다. 상기의 결과로부터 산란종계의 후기 난각질 및 생산성의 개선을 위해서는 사료 내 홍화씨 및 키토산과 같은 Ca의 이용성에 영향을 미치는 성분을 적절히 활용함으로써 후기 난각질과 부화율의 개선을 통해 종란 생산성을 향상시킬 수 있을 것으로 사료된다.

• 한국가금학회지
• /
• 제33권3호
• /
• pp.217-224
• /
• 2006

본 시험은 남은 음식물을 산란계 사료에 1, 3, 5, 10 및 20% 첨가하여, 산란계의 사료 섭취량, 산란율 및 계란 품질에 미치는 영향을 구명하고자 실시하였다. 시험축은 50주령 산란계(White Leghorn종) 162수를 이용하였으며, 처리구는 남은 음식물을 0, 1, 3, 5, 10, 20% 첨가하여 4주간 급여하였다. 시험기간 중 사료 섭취량, 난중은 첨가수준별과 주령별 처리구 사이에 차이가 없었다(p>0.05). 그러나 산란율은 FW 20% 처리구에서 1, 2, 3 주째 산란율의 감소가 있었으나, 4주째 회복하였다(p<0.05). 난각 두께와 난황 계수는 전 처리구에서 차이가 없었으나(p>0.05), 난각 강도는 3주째와 4주째에 10% FW 처리구에서 각각 $4.13kg/cm^2$와 $4.04kg/cm^2$로 나타나 첨가 수준에 따른 차이가 있었다(p<0.05). 호우 유니트와 난황색은 20% FW 처리구에서 4주째에 각각 92.3과 9.4로 남은 음식물 사료의 첨가 수준에 따라 주령별 뚜렷한 차이를 보였다(p<0.05). 본 연구 결과 FW를 20% 이상 첨가시에 산란율이 감소했지만, 5% 첨가시에 산란율이 유지되었으며, 난질이 개선되어 남은 음식물 사료의 영양소 요구량 수준 개선으로 사료 자원으로서 가치가 증진될 것으로 사료된다.

• 한국축산식품학회지
• /
• 제38권5호
• /
• pp.1080-1091
• /
• 2018

The eggshell, which is a complex and highly ordered structure, is very important factor for food safety and egg marketing. This study investigated the changes in eggshell structure and shell components in relationship to hen age. For this study, we examined the histological change of the endometrium of the 30-, 60-, and 72-wk-old commercial layers, and analyzed the ultrastructure and ionic composition of their eggshells. The results showed that histological deformation, fibrosis, atrophy and elimination of micro-villi in the uterus endometrium were found through microscopic observation that was associated with increasing hen age. Concentration of blood-ion components such as $Ca^{2+}$, $Na^+$, $K^+$, and $Cl^-$ ions did not change with age. Along with the results from the ultrastructure analysis of the eggshell, the palisade layer ratio and the density of mammillary knobs were significantly decreased in older hens. In addition, the type B mammillary knobs were frequently observed with increasing hen age. In the mineral element assay from the eggshell, $Ca^{2+}$, $S^{2-}$, and $Co^{2+}$ significantly decreased with increasing hen age, whereas $Na^+$, $K^+$, and $V^{2+}$ significantly increased. Therefore, the damages of endometrial tissue inhibit the processes of ion transmission and the crystallization of eggshell formation, resulting in a large and non-uniform mammillary knob formation. This means the conditions of endometrial cells affect the formation of the eggshell structure. In conclusion, hen aging causes the weakness of the eggshell and degrades the eggshell quality.

• 한국가금학회지
• /
• 제43권2호
• /
• pp.89-96
• /
• 2016

This study aimed to determine the effect of different dietary level of rice bran extract (RBO) on the laying performance, egg quality, blood parameter, cholesterol, and fatty acids in yolk of Hy-Line Laying hens. In all, 144 Hy-Line Brown laying hens (29 weeks old) were randomly allocated to one of 4 dietary treatments, with 4 replicates per treatment. A commercial basal diet was used and three additional diets were prepared by supplementing 2.5, 5.0 or 10.0 g/kg of RBO to the basal diet. The experimental diets were fed on an ad libitum basis to the bird during 8 weeks. Hen-day egg production increased (quadratic, p<0.05) with inclusion level of RBO, but feed intake, egg weight, and egg mass were not influenced by inclusion of level of RBO in diet. However, the supplementation of RBO did not have an effect on eggshell strength, eggshell thickness, egg yolk color, and HU during the feeding trial. There were no significant differences in the level of leukocyte. However, heterophil and lymphocytes decreased (quadratic, p<0.01) with inclusion level of RBO. H:L ratio tended to decrease (linear p=0.08) with inclusion level of RBO. As expected, increasing inclusion level of RBO in diets decreased (linear, p<0.01) the concentrations of total cholesterol in plasma. AST, ALT, glucose, and albumin were not affected by inclusion of RBO in diets. Egg yolk cholesterol increased (linear and quadratic, p<0.05) with inclusion level of RBO in diet. The results of this study indicate that dietary supplementation of RBO improves laying performance and decreased total cholesterol and egg yolk cholesterol levels in laying hens. Therefore, dietary RBO is considered a valuable functional ingredient to improve the performance of birds.

• Asian-Australasian Journal of Animal Sciences
• /
• 제33권8호
• /
• pp.1217-1223
• /
• 2020

Objective: Eggshells with a uniform color and intensity are important for egg production because many consumers assess the quality of an egg according to the shell color. In the present study, we evaluated the influence of dominant effects on the variations in eggshell color after 32 weeks in a crossbred population. Methods: This study was conducted using 7,878 eggshell records from 2,626 hens. Heritability was estimated using a univariate animal model, which included inbreeding coefficients as a fixed effect and animal additive genetic, dominant genetic, and residuals as random effects. Genetic correlations were obtained using a bivariate animal model. The optimal diagnostic criteria identified in this study were: L^🟉 value (lightness) using a dominance model, and a^🟉 (redness), and b^🟉 (yellowness) value using an additive model. Results: The estimated heritabilities were 0.65 for shell lightness, 0.42 for redness, and 0.60 for yellowness. The dominance heritability was 0.23 for lightness. The estimated genetic correlations were 0.61 between lightness and redness, -0.84 between lightness and yellowness, and -0.39 between redness and yellowness. Conclusion: These results indicate that dominant genetic effects could help to explain the phenotypic variance in eggshell color, especially based on data from blue-shelled chickens. Considering the dominant genetic variation identified for shell color, this variation should be employed to produce blue eggs for commercial purposes using a planned mating system.

• Animal Bioscience
• /
• 제34권3_spc호
• /
• pp.443-448
• /
• 2021

Objective: Astaxanthin is a natural super antioxidant. The present study was carried out to investigate the effect of astaxanthin rich Phaffia rhodozyma (PR) supplementation in diets on laying production performance, egg quality, antioxidant defenses and immune defenses in laying hens. Methods: A total of five hundred and twelve 60-week-old Lohmann Brown laying hens (2,243±12 g) were randomly assigned to four groups, each including 4 replicates with 32 birds per replicate. Astaxanthin rich PR was added to corn-soybean meal diets to produce experimental diets containing 0 (Control), 800 mg/kg, 1,200 mg/kg, and 1,600 mg/kg PR, respectively. The astaxanthin content in the diet was 0.96 mg/kg, 1.44 mg/kg and 1.92 mg/kg respectively. Results: Results showed that dietary PR supplementation tended to increase daily feed intake (p = 0.0512). There was no effect of astaxanthin rich PR on Haugh units, albumen height, egg shape index, eggshell strength, and eggshell thickness at weeks 6 (p>0.05). However, egg yolk color was significantly improved (p<0.05). In addition, astaxanthin rich PR supplementation significantly increased serum glutathione peroxidase and superoxide dismutase activity (p<0.05), increased serum immunoglobulin G content (p<0.05), and reduced malondialdehyde content (p<0.05) in laying hens. Conclusion: In conclusion, astaxanthin rich PR can improve the color of egg yolk, enhance the antioxidant defenses, and regulate the immune function.

• 한국가금학회:학술대회논문집
• /
• 한국가금학회 2003년도 제20차 정기총회 및 학술발표회
• /
• pp.84-86
• /
• 2003

An experiment was conducted to determine the effects of dietary supplementation of yeast Rhodotourula glutinis(Glutincus) on the performance and egg quality of layers. A total of 360 ISA Brown layers of 72 weeks old were assigned to one of the following 6 diets ：control, 25 ppm ${\beta}$-carotene. 0.5％, 1％, 2％ and 4％ Glutinicus supplemented diet. Each treatment was replicated three times with 20 birds housed in 2 birds cage units. Glutinicus supplemented at the level of 0.5％ significantly(p＜0.05) improved egg production and FCR. Soft and broken egge production rate decreased as the level of Glutinicus supplementation increased. Eggshell was highest in Glutinicus 4％ supplementation. Egg yolk color increased linearly as the level of Glutinicus supplementation increased up to 2％ of the diet. It was concluded that Glutinicus supplementation at the level of 0.5％ can be recommended for the improvement of egg production while 2.0％ can be recommended for egg yolk pigmentation.

• 한국가금학회지
• /
• 제25권4호
• /
• pp.177-183
• /
• 1998

한국재래닭의 육성기 및 산란기 능력을 연구하기 위하여 적갈색, 황갈색, 흑색 3계통 810수를 공시하여 64주간 사양시험을 실시하였다. 급여사료는 한국표준 닭사료급여기준(1994)에 준하여 급여하였으며 그 결과는 다음과 같다. 1. 육성률은 적갈색이 가장 높았고 흑색이 가장 낮으며, 체중은 흑색이 무거웠고 갈색계통은 비슷하였지만 통계적 유의성은 없었다. 2. 20주령까지 사료섭취량은 계통간 비슷하였으며, 50％ 산란일령은 황갈색이 가장 빨랐으나 유의성은 인정되지 않았다. 3. 전기간 평균 산란율은 황갈색, 흑색, 적갈색 순이었으며(P<0.05), 난중은 적갈색이 약간 무거웠다(P<0.05). 4. 사료섭취량은 3계통 모두 105g으로 동일하였으며, 사료요구율은 황갈색이 다른 계종에 비하여 개선되었다(P<0.05). 5. 난각강도는 계통간 차이가 없었으며 난각두께는 난중이 무거운 적갈색이 두꺼운 것으로 나타났고 (P<0.05), 난질은 계통간 차이가 없었다. 6. 수정율은 산란중기 및 후기에서 황갈색이 가장 낮았고 적갈색이 가장 높게 나타났다(P<0.05). 7, 부화율은 산란중기에서는 계통간 차이가 없었으나, 산란후기에는 갈색계통에 비하여 흑색이 낮았다(P<0.05). 8. 한국재래닭의 육성기 및 산란기 능력은 계통간 큰 차이가 없었으나, 황갈색의 산란율이 다른 계통에 비하여 높았으며 사료요구율도 개선되었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권8호
• /
• pp.1179-1189
• /
• 2006

This experiment was designed to examine the effects of supplemental vitamin D on laying performance, metabolic profile and egg quality of hens fed diets containing different fat sources and levels. Lohman strains (n = 480) were assigned to one of 10 diets: basal diet (BD), BD plus 2.5 and 5.0% sunflower oil (SO) or tallow (T) at vitamin D provided $1{\times}$ and $3{\times}$ of the current recommendation. The experiment lasted from week 30 to 44 of age. Each diet was tested in 12 replicate cages of 4 hens. Production, metabolism, and egg quality data were subjected to three-way ANOVA. Both fats decreased feed intake (FI) as compared to BD. Increasing SO and T levels linearly decreased and quadratically increased FI, respectively. The dietary factors did not affect egg production (EP) and egg weight. Vitamin D supplementation increased and decreased EP when diets contained SO and T, respectively. Feed conversion efficiency (FCE) for hens fed SO was lower than for hens fed T. However, increasing T level improved FCE, whereas increasing SO level worsened FCR. Vitamin D supplementation increased serum vitamin D and glucose concentrations. Vitamin D supplementation also caused a decrease and an increase in serum vitamin D concentration when diets contained SO and T, respectively. Serum glucose concentration for hens fed SO was lower than hens fed T. Increasing fat level linearly increased serum triglyceride and VLDL concentrations, regardless of the fat type. Increasing SO level linearly decreased serum cholesterol concentration. Vitamin D supplementation did not alter lipid metabolites. The dietary factors did not affect serum total protein, Ca, and P concentrations. As compared with BD, feeding SO decreased dry tibia and ash weights more than feeding T. Vitamin D supplementation tended to increase dry tibia weight and decrease tibia ash weight. Eggshell strength and thickness, yolk and albumen indexes, and Haugh unit were not responsive to the dietary factors. Eggshell strength quadratically increased with increasing T level. Yolk color for hens fed SO was lower than for hens fed T. The dietary factors did not affect most of yolk fatty acids. Increasing SO level quadratically decreased yolk $C_{18:2}$ concentration. Vitamin D supplementation increased and decreased yolk $C_{18:2}$ concentration when diets contained SO and T, respectively. In conclusion, increasing fat level improved laying performance without altering metabolic profile and egg quality. Vitamin D supplementation had minor alteration effects on laying performance, metabolic profile, and egg quality in response to fat feeding.