Effect of Energy and Protein on Performance,Egg Components,Egg Solids,Egg Quality,and Profits in Molted Hy-Line W-36 Hens

An experiment was conducted to determine the influence of dietary energy on performance, egg composition, egg solids, egg quality, and profits of Hy-Line W-36 hens fed different protein levels. The experiment was designed as a 4 × 3 factorial arrangement with 4 added dietary energy levels (0, 79, 158, and 238 kcal of ME/kg) and 3 protein levels (14.89, 16.06, and 17.38%). The basal diets of 17.38, 16.06, and 14.89% protein contained 2,751, 2,784, and 2,815 kcal of ME/kg, respectively. This study lasted 12 wk. Molted Hy-Line W-36 hens (n = 1,440) in phase 1 (70 wk of age) were randomly divided into 12 treatments (8 replicates of 15 hens per treatment). Protein had a significant effect on egg production, egg mass, feed intake, feed conversion, egg weight, percentage of egg shell components, yolk color, and yolk and albumen weight. As dietary energy increased from 0 to 238 kcal of ME/kg by addition of poultry oil, feed intake linearly decreased. Increasing dietary energy also significantly increased BW and egg yolk color. As dietary energy increased, percentage yolk solids increased at the 2 greater dietary protein levels, whereas egg-specific gravity linearly decreased at the 17.38% protein level. Increasing dietary energy and protein significantly improved feed conversion. Increasing protein intake significantly increased albumen and yolk weight but had no influence on yolk, albumen, or whole egg solids. Because feed ingredient and egg prices vary, there can be no fixed ideal dietary energy level for optimal profits during molt phase 1 (70 to 81 wk).     

Comparative Pigmentation Efficiency of High Dietary Levels of Apo-Ester and Marigold Extract on Quality Traits of Whole Liquid Egg of Two Strains of Laying Hens

This trial was carried out to compare the effect of the dietary supplementation of high doses of either synthetic pigment ethyl ester of β-apo-8′-carotenoic acid (apo-ester) or natural pigments, mainly lutein and zeaxanthin, extracted from Tagetes erecta, on egg quality of hens laying brown shell eggs (ISA Brown) and white shell eggs (Hy-Line White W-36). The hens of each strain were divided into 6 groups and fed a corn-soybean basal diet supplemented either with 40, 60, and 80 ppm of apo-ester (APO) or with 120, 180, and 240 ppm of marigold extract (MAR). Egg pigmentation rose linearly and significantly (P < 0.01) as the dietary levels of apo-ester increased, but this did not occur when MAR supplementation was used. The amount of β-carotene equivalents in whole liquid egg of MAR treatments was almost constant with varying pigment dietary dose and was significantly lower (P < 0.01) than in APO treatments. In both hen strains, whole liquid egg redness (a*) and yellowness (b*) were higher with APO supplementation. The egg component weights were highly affected (P < 0.01) by the hen strain, with yolk:egg ratio higher in the Hy-Line. The trial confirms that in spite of the higher level of MAR supplementation, APO has a better efficiency in whole liquid egg pigmentation. The ISA Brown hens showed a better ability to absorb dietary carotenoids than did the Hy-Line White.     

Effect of dietary defatted diatom biomass on egg production and quality of laying hens

Background： This study was to determine if feeding laying hens with defatted diatom microalgal biomass （DFA） from biofuel production affected their egg production and health status. Methods： Five replicates of 5 individually caged ISA Babcock White leghorn hens were fed 4 diets, including a corn-soybean meal control diet, a diet containing 7.5% DFA substituting for soybean meal, and diets containing 7.5% or 15% DFA substituting for corn and soybean meal. Body weights, feed intake, feed conversion ratio （FCR）, rate of egg production, egg size, egg mass, and several characteristics of eggs were determined at 4 and 8 wk. Venous blood was sampled at 4 and 8 wk for measurement of 5 biomarkers of health. Results： The15% DFA diet decreased （P 〈 0.05） feed intake, egg production, and plasma uric acid concentrations as compared with the control diet, but increased （P 〈 0.05） egg albumen weight and height compared with the 7.5% DFA diets. The two levels of DFA produced dose-dependent （P 〈 0.05） changes in three color measures of egg yolk, without affecting four hen plasma biochemical indicators of health. Conclusions： Feeding laying hens with 7.5% DFA in the corn-soybean meal diet for 8 wk had no adverse effect on their health, egg production, or egg quality, but 15% inclusion reduced feed intake, egg production, and efficiency of feed utilization.     

Parental diet effects on egg component weights and shell quality

An experiment was conducted to investigate the effects of feeding laying hens a low protein and energy diet (LPE), a high protein and energy diet (HPE), and a commercial protein and energy diet (control) on whole egg components, egg weight, and shell quality. The hens were fed their respective diets from 15 to 30 wk of age. At 30 wk of age, egg component weight and percentages were measured along with eggshell quality. The results demonstrated that birds fed the LPE diet had significantly lower albumen, yolk, and total egg weights that the control and HPE groups. The LPE group had significantly lower levels of total albumen protein than the control group. The HPE hens had significantly lower shell thickness and pore concentration than the LPE group, demonstrating that dietary levels of CP and ME can alter not only shell quality component but also albumen protein levels.     

谷氨酰胺对免疫应激蛋鸡经济性状的影响

为探讨谷氨酰胺(Gln)对免疫应激产蛋高峰期鸡生产性能和蛋品质影响,选取健康的37周龄海兰褐产蛋鸡300只,随机分为5组,每组5重复,每重复12只。Ⅰ组为对照组,饲喂基础日粮,Ⅱ、Ⅲ、Ⅳ和Ⅴ组为免疫应激组,在日粮中分别添加0%、0.6%、0.8%和1.0%的Gln。试验第4天对Ⅱ～Ⅴ组蛋鸡进行腿部肌肉注射新城疫冻干苗和油苗,Ⅰ组同部位注射等量生理盐水。结果显示,免疫应激导致蛋鸡生产性能和蛋品质有所降低,Gln添加Ⅲ组的产蛋率恢复较其他应激组快(P<0.05),Ⅱ组的料蛋比显著高于Ⅰ组(P<0.05),Ⅳ组的采食量较低,平均蛋重较高,试验后期Gln可改善蛋壳强度和蛋黄颜色(P>0.05)。免疫应激条件下,饲料添加Gln可提高蛋鸡生产性能,改善蛋品质。     

饲粮缬氨酸水平对蛋鸡生产性能、蛋品质及血清生化指标的影响

本文旨在研究饲粮不同缬氨酸水平对蛋鸡生产性能、蛋品质及血清生化指标的影响,并探讨蛋鸡饲粮中缬氨酸的最适添加量.试验选用720只体重相近的40周龄的海兰褐壳蛋鸡,随机分成5组,每组4个重复,每个重复36只鸡,分别饲喂缬氨酸水平为0.6％、0.7％、0.8％、0.9％、1.0％的饲粮,试验期为56 d.结果表明:1)0.8％水平组料蛋比和1.0％水平组平均日采食量分别最低,与其他各组均差异显著(P＜0.05);各组产蛋率、平均蛋重和日产蛋均重均无显著差异(P＞0.05).2)0.8％水平组蛋壳强度最大,1.0％水平组蛋清蛋白质含量最低,与其他各组均差异显著(P＜0.05)或有显著的趋势(P＜0.10);各组蛋壳厚度、哈夫单位、蛋黄颜色、蛋白高度、蛋黄和蛋清相对重均无显著差异(P＞0.05).3)0.8％水平组血清葡萄糖含量最高,显著高于其他各组(P＜0.05);0.8％水平组血清尿素氮和尿酸含量最低,总氨基酸含量最高,与其他各组均有差异显著的趋势(P＜0.10).4)二次曲线分析表明:当饲粮代谢能为11.31 MJ/kg、粗蛋白质水平为15.81％、赖氨酸水平为0.77％时,以料蛋比为评价指标,产蛋高峰期蛋鸡缬氨酸需要量为0.78％,以蛋壳强度和血清白蛋白含量为评价指标,缬氨酸需要量分别为0.81％和0.75％.由此可知,基础饲粮中添加一定量的缬氨酸可降低产蛋高峰期蛋鸡料蛋比,增强蛋壳强度和提高血清葡萄糖含量.     

饲料代谢能水平对农大3号小型蛋鸡生产性能的影响

180只140日龄的农大3号小型蛋鸡随机平均分为A、B、C、D、E五组,每组6个重复,每个重复6只鸡,体重大小基本一致,各组间生产性能差异不显著。分别饲喂代谢能水平11.5MJ/kg、11.3MJ/kg、11.1MJ/kg、10.9MJ/kg和10.7MJ/kg的饲料,其他营养成分含量设计上保持一致。通过30周的观察,发现在产蛋高峰前饲喂稍低能值的饲料(10.9MJ/kg)有利于采食量的增加和产蛋率的迅速上升。在一定饲料代谢能值范围内,饲料能值的高低对小型蛋鸡采食量影响不显著,所以从产蛋高峰期开始,必须使用代谢能水平较高的日粮,才能满足小型蛋鸡维持高产蛋率对能量的需求。综合来看,饲料代谢能为11.3MJ/kg时,小型蛋鸡有较高的产蛋量和饲料报酬。     

理想氨基酸模式下低粗蛋白质饲粮对蛋鸡生产性能的影响

本试验旨在研究以理想氨基酸(AA)模式配制的低粗蛋白质(CP)饲粮对21～32周龄蛋鸡生产性能、蛋品质、全血氨浓度和血浆尿酸浓度及粪氮含量的影响.试验选用540只体重相近的健康海兰灰蛋鸡,随机分为5组,每组6个重复,每个重复18只鸡,分别饲喂等能量( 11.00 MJ/kg)的5种CP水平(17.00％、16.50％、16.00％、15.50％和15.00％)的饲粮,试验期12周.结果表明:在理想AA模式下降低饲粮CP水平,蛋鸡产蛋率显著提高(P＜0.05),平均蛋重有降低的趋势(P=0.06),但对平均日采食量、日产蛋重和蛋料比无显著影响(P＞0.05);降低饲粮CP水平极显著影响了蛋白高度和哈氏单位(_P＜0.01),显著影响了蛋黄颜色(P＜0.05),未显著影响蛋壳厚度和蛋壳强度(P＞0.05);饲粮CP水平对各鸡蛋成分均无显著影响(P＞0.05),但鸡蛋蛋白含量随饲粮CP水平的降低有降低的趋势(P=0.09);饲粮CP水平对血浆尿酸浓度及全血氨浓度均无显著影响(P＞0.05);降低饲粮CP水平极显著降低了蛋鸡粪氮含量(P＜0.01).由此可见,在理想AA模式下,适当降低饲粮CP水平可提高蛋鸡产蛋率,改善鸡蛋品质,降低粪氮含量.     

Effects of supplemental L-carnitine in drinking water on performance and egg quality of laying hens exposed to a high ambient temperature

The present study was conducted to investigate effects of L-carnitine supplied with drinking water on performance and egg quality of laying hens under high environmental temperature. In the study, 47-week-old laying hens (Brown hisex) were divided into two groups (control and treatment) and fed with a standard layer diet. Treatment group was received 50 p.p.m L-carnitine with drinking water for an 8-week period. Throughout the study, 8 h hot (35-37 degrees C) and 16 h thermoneutral (20-22 degrees C) environmental temperature regime was employed daily. The results showed that L-carnitine supplementation affected some egg quality characteristics of layers under high environmental temperature. Relative albumen weight and height were increased (p < 0.05) by supplemental L-carnitine. Live weight gain, feed intake, egg mass, egg weight, yolk weight, shell weight, yolk index, egg-shape index, yolk colour score and shell thickness were not affected (p < 0.05) by L-carnitine. It is concluded that L-carnitine supplementation in laying hens could have potential to improve albumen quality under high environmental temperature.     

The effects of dietary fat and bird age on the weights of eggs and egg components in the laying hen

1. A low-fat diet or an isoenergetic and isonitrogenous high-fat diet containing 55 g maize oil/kg were fed to laying hens at different stages during the laying year in two experiments. 2. Feeding the high-fat diet to young hens resulted in a rapid increase of 2.5 g in egg weight, made up of increases in both yolk and albumen weights. 3. Switching the diets at 50 weeks caused changes in egg weight that were accounted for entirely by changes in egg albumen weight. 4. Feeding the high-fat diet from 46 weeks in a second experiment increased egg and egg albumen weights by 1.26 and 1.34 g respectively. 5. The increase in egg weight with age was associated with a greater increase in the proportion of yolk, at the expense of albumen, compared to egg weight increases related to dietary fat. 6. It is concluded that dietary fatty acids increase egg weight by a mechanism different from that causing age-related increases in weight and that the mechanism involves a stimulation of oviduct protein synthesis.     

Effect of dietary energy,protein, and a versatile enzyme on hen performance,egg solids,egg composition,and egg quality of Hy-Line W-36 hens during second cycle,phase two

This study was conducted to evaluate the effect of Rovabio, dietary energy, and protein on performance, egg composition, egg solids, and egg quality of commercial Leghorns in phase 2, second cycle. A 4 × 2 × 2 factorial arrangement of treatments comprising 4 dietary energy levels (2,791, 2,857, 2,923, and 2,989 kcal of ME/kg) and 2 protein levels (15.5 and 16.1%) with and without Rovabio was used. Hy-Line W-36 hens (n = 1,920, 87 wk old) were randomly divided into 16 dietary treatments (8 replicates of 15 hens per treatment). The trial lasted 12 wk. Dietary protein significantly increased feed consumption but decreased yolk color. As dietary energy increased from 2,791 to 2,989 kcal of ME/kg, feed consumption decreased from 98.0 to 94.9 g per hen daily, and yolk color increased from 5.27 to 5.56. There was a significant interaction among dietary protein, energy, and Rovabio on egg production, BW, egg mass, feed conversion, and yolk solids. Egg weight of hens fed the diets supplemented with Rovabio was significantly greater than that of hens fed the diets without Rovabio during wk 3 and 4. However, Rovabio did not significantly influence average egg weight (87 to 98 wk of age). Rovabio supplementation significantly increased BW of hens. These results suggest Rovabio had a small but significant influence on nutrient utilization of commercial Leghorns during phase 2 of the second cycle.     

标准回肠可消化氨基酸模式下降低饲粮粗蛋白质水平对蛋鸡生产性能、蛋品质及氮平衡的影响

本试验旨在研究标准回肠可消化(SID)氨基酸(AA)模式下,降低饲粮粗蛋白质(CP)水平对海兰灰蛋鸡生产性能、蛋品质及氮平衡的影响。选取540只20周龄体重相近且健康的海兰灰蛋鸡,随机分为5个处理,每个处理6个重复,每个重复18只鸡,预试期1周,正试期12周,采食等代谢能(11.82 MJ/kg)、等赖氨酸(Lys,SID Lys为0.831%)、相同AA模式、不同CP水平(18.0%、17.5%、17.0%、16.5%和16.0%)的试验饲粮。结果表明:SID AA模式下,降低饲粮CP水平可极显著降低平均蛋重和CP摄入量(P<0.01),显著降低鸡蛋浓蛋白高度(P<0.05),显著降低蛋鸡摄入氮和排出氮(P<0.05),有提高氮表观利用率的趋势(P=0.05);数据偏相关分析表明,饲粮中SID AA模式外的精氨酸、苯丙氨酸和亮氨酸水平下降与平均蛋重下降显著相关(P<0.05),与浓蛋白高度下降无显著相关(P>0.05)。结果提示,SID AA模式下,降低饲粮CP水平,除影响平均蛋重和浓蛋白高度外,对其他生产性能、蛋品质及血液生化指标影响较小,平均蛋重的下降与低CP饲粮中精氨酸、苯丙氨酸和亮氨酸不足有关;AA平衡的低CP饲粮,可在维持较高生产性能的同时减轻蛋鸡粪氮排出。     

苜蓿多糖对夏季高温环境下蛋鸡生产性能及蛋品质的影响

本试验旨在研究夏季高温环境下在饲粮中添加苜蓿多糖对蛋鸡生产性能及蛋品质的影响。将540只156日龄海兰褐蛋鸡随机分成6组,每组6个重复,每个重复15只鸡。对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加250、500、1 000、2 000和4 000 mg/kg苜蓿多糖的试验饲粮。试验期为6周。结果显示:与对照组相比,1)饲粮中添加不同水平苜蓿多糖对平均蛋重、平均日采食量、不合格蛋率和死淘率均无显著影响(P0.05),而添加500、1 000和4 000 mg/kg苜蓿多糖显著提高了蛋鸡的产蛋率(P0.05),添加500、1 000、2 000和4 000 mg/kg苜蓿多糖显著降低了料蛋比(P0.05)。2)饲粮中添加不同水平苜蓿多糖对蛋白高度和哈夫单位均无显著影响(P0.05);250 mg/kg苜蓿多糖添加组第4和6周末的蛋黄颜色显著提高(P0.05);500 mg/kg苜蓿多糖添加组第6周末的蛋形指数显著降低(P0.05),第1、4和6周末的蛋黄颜色显著提高(P0.05);1 000 mg/kg苜蓿多糖添加组第4和6周末的蛋壳颜色显著加深(P0.05),第1、2和4周末的蛋壳强度和蛋壳厚度显著提高(P0.05),第1和6周末的蛋形指数显著降低(P0.05),第1、2、4和6周末的蛋黄颜色显著提高(P0.05);2 000 mg/kg苜蓿多糖添加组第1和4周末的蛋壳厚度显著提高(P0.05),第6周末的蛋形指数显著降低(P0.05),第1、4和6周末的蛋黄颜色显著提高(P0.05);4 000 mg/kg苜蓿多糖添加组第4周末的蛋壳颜色显著加深(P0.05)且蛋壳强度显著提高(P0.05),第1和4周末的蛋壳厚度显著提高(P0.05),第6周末的蛋形指数显著降低(P0.05),第1、4和6周末的蛋黄颜色显著提高(P0.05)。结果表明,夏季高温环境下,在饲粮中添加适量的苜蓿多糖可以有效缓解蛋鸡的热应激,提高蛋鸡的生产性能,改善蛋品质,且适宜添加量为1 000 mg/kg。     

不同干燥工艺加工的苜蓿粗多糖对蛋鸡生产性能、蛋品质和血清、鸡蛋中抗体含量的影响

本试验旨在研究不同干燥工艺加工的苜蓿粗多糖对蛋鸡生产性能、蛋品质、器官指数和血清、鸡蛋中抗体含量的影响。选取54只38周龄的京红1号产蛋鸡,随机分为3组,每组18个重复,每个重复1只鸡,单笼饲养。对照组饲喂玉米-豆粕型基础饲粮,试验组分别饲喂在基础饲粮中添加1 000 mg/kg微波真空干燥所得苜蓿粗多糖1(ACPS1)和减压烘干干燥所得苜蓿粗多糖2(ACPS2)。试验期65 d。结果表明:与对照组相比,1)在试验第28~36天,ACPS1组蛋鸡的平均日采食量显著增加(P0.05);饲粮中添加不同干燥工艺加工的苜蓿粗多糖对蛋鸡各阶段的产蛋率和平均日增重均无显著影响(P0.05)。2)试验第63天,ACPS1组蛋鸡的蛋黄颜色显著增加(P0.05);试验第30天,饲粮中添加不同干燥工艺加工的苜蓿粗多糖对蛋鸡的蛋壳颜色、蛋黄颜色、蛋白高度和哈氏单位均无显著影响(P0.05)。3)ACPS1组蛋鸡的肝脏指数显著增加(P0.05),ACPS2组的卵巢指数显著降低(P0.05);且ACPS1组的肝脏指数和卵巢指数均显著高于ACPS2组(P0.05)。饲粮中添加不同干燥工艺加工的苜蓿粗多糖对蛋鸡的脾脏指数和输卵管指数均无显著影响(P0.05)。4)ACPS1组蛋鸡血清中免疫球蛋白Y(Ig Y)含量显著增加(P0.05),ACPS1和ACPS2组血清中新城疫抗体(NDV-Ab)、蛋黄中NDV-Ab、蛋清中免疫球蛋白A(Ig A)和免疫球蛋白M(Ig M)含量均显著增加(P0.05);且ACPS1组蛋黄中NDV-Ab、蛋清中Ig A和Ig M含量均显著高于ACPS2组(P0.05)。以上结果表明,饲粮中添加苜蓿粗多糖能加深蛋鸡的蛋黄颜色,增加血清和鸡蛋中的抗体含量,且ACPS1的效果更佳。     

Effect of dietary defatted diatom biomass on egg production and quality of laying hens

Background

This study was to determine if feeding laying hens with defatted diatom microalgal biomass (DFA) from biofuel production affected their egg production and health status.

Methods

Five replicates of 5 individually caged ISA Babcock White leghorn hens were fed 4 diets, including a corn-soybean meal control diet, a diet containing 7.5% DFA substituting for soybean meal, and diets containing 7.5% or 15% DFA substituting for corn and soybean meal. Body weights, feed intake, feed conversion ratio (FCR), rate of egg production, egg size, egg mass, and several characteristics of eggs were determined at 4 and 8 wk. Venous blood was sampled at 4 and 8 wk for measurement of 5 biomarkers of health.

Results

The 15% DFA diet decreased (P <?0.05) feed intake, egg production, and plasma uric acid concentrations as compared with the control diet, but increased (P <?0.05) egg albumen weight and height compared with the 7.5% DFA diets. The two levels of DFA produced dose-dependent (P <?0.05) changes in three color measures of egg yolk, without affecting four hen plasma biochemical indicators of health.

Conclusions

Feeding laying hens with 7.5% DFA in the corn-soybean meal diet for 8 wk had no adverse effect on their health, egg production, or egg quality, but 15% inclusion reduced feed intake, egg production, and efficiency of feed utilization.     

高铁高碘日粮对蛋品质的影响

用高铁高碘日粮饲喂产蛋母鸡,观察对蛋品质的影响。结果表明,蛋黄重、蛋黄占蛋重比略有下降,蛋白占蛋重比、哈夫单位有所上升;蛋壳占蛋重比、蛋壳厚度及蛋壳密度无明显变化。提示高铁高碘日粮不会引起蛋品质的明显下降。     

日粮中添加辣诺素对海兰褐蛋鸡产蛋性能和蛋品质的影响

本试验旨在研究日粮中添加辣诺素（辣木和诺丽果的提取物）对蛋鸡生产性能及蛋品质的影响。将产蛋高峰期（22周龄）的海兰褐商品蛋鸡540只随机分为6个处理,每个处理6个重复,每个重复15只鸡。负对照组（NC）饲喂基础日粮,正对照组（PC）饲喂添加50 mg/kg杆菌肽锌的基础日粮,4个试验组分别饲喂添加0.25、0.50、0.75和1.00 g/kg辣诺素（LNS）的基础日粮。试验期24周。结果显示：①日粮处理对蛋鸡试验前期和后期生产性能均无显著影响（P>0.05）,试验后期添加0.50和0.75 g/kg辣诺素有改善料蛋比的趋势（P=0.087）;日粮处理对试验前期和后期鸡蛋蛋形指数、蛋壳强度、蛋壳厚度、蛋黄重和哈氏单位均无显著影响（P>0.05）,但日粮中添加杆菌肽锌和辣诺素有提高蛋壳强度的趋势（P=0.062）,其中以添加0.75g/kg辣诺素组鸡蛋强度最高。②与正、负对照组相比,添加辣诺素显著增加了生蛋黄和熟蛋黄的罗氏蛋黄色比率（P<0.05）,显著降低了蛋黄胆固醇的含量（0.25 LNS组除外）（P<0.05）。③与负对照组相比,添加0.50 g/kg辣诺素显著提高了鸡蛋总黄酮、二十二碳六烯酸（DHA）、卵磷脂、亚麻酸和亚油酸含量（P<0.05）。综合以上试验结果,辣诺素作为饲料添加剂具有提高鸡蛋营养品质的功能,考虑到添加成本,产蛋鸡日粮中添加0.25~0.50 g/kg为宜。     

Performance and Egg Characteristics of Laying Hens Fed Diets Incorporated with Poultry By-Product and Feather Meals

The effects of poultry by-product meal (PBPM) and feather meal (FM) incorporated separately and in combination in the diet on laying hen performance and egg characteristics during postpeak production were determined. Bovans White strain laying hens, 42 wk of age, were fed diets with 0% PBPM and FM, 5% FM, 5% PBPM, or 4% FM + 4% PBPM. Egg production, feed intake, and egg mass were not significantly affected by dietary treatments, whereas egg weight and feed conversion ratio (FCR) were significantly affected. Egg weights of hens receiving 4% FM + 4% PBPM were significantly lower than those fed the control diet, whereas those fed 5% FM or 5% PBPM were intermediate. FCR was significantly improved by the diets containing 5% FM or 5% PBPM compared with the diet containing 4% FM + 4% PBPM. Dietary PBPM decreased Haugh units, but FM did not. Egg breaking strength, shell weight, and weights of albumen and yolk were not affected by treatments. The results suggested that FM or PBPM could be incorporated up to 5% singly or up to 8% in combination in layer diets but with possible detrimental effects on Haugh units, egg weight, and FCR.     

循环高温对蛋鸡生产性能、蛋壳品质及钙磷代谢的影响

本试验旨在模拟夏季蛋鸡舍内的循环高温,研究不同温度对蛋鸡生产性能、蛋壳品质及钙磷代谢的影响。选取28周龄高产海兰褐蛋鸡288只,随机分为21℃适温组(自由采食)、27~30℃循环高温组(自由采食)、29~35℃循环高温组(自由采食)和21℃采食配对组(按前1 d 29~35℃循环高温组的采食量饲喂),每个组6个重复,每个重复12只鸡,分别饲养于4个人工环境控制舱内,试验期4周。结果表明:与21℃适温组相比,27~30℃循环高温组蛋鸡平均日采食量、体增重和平均蛋重显著降低(P0.05),蛋壳强度显著降低(P0.05),蛋鸡钙、磷的代谢率差异不显著(P0.05),但钙、磷的吸收量显著降低(P0.05),除蛋黄颜色显著降低(P0.05)外,鸡蛋品质其他相关指标差异不显著(P0.05);而29~35℃循环高温组除平均日采食量、体增重和平均蛋重显著降低(P0.05)外,产蛋率同样显著降低(P0.05),蛋壳厚度和蛋壳强度均显著降低(P0.05),破蛋率显著升高(P0.05),蛋鸡钙、磷的代谢率差异不显著(P0.05),而钙、磷吸收量同样显著降低(P0.05),鸡蛋蛋白高度和蛋黄颜色均显著降低(P0.05)。与21℃采食配对组相比,29~35℃循环高温组平均蛋重显著降低(P0.05),料蛋比显著提高(P0.05),蛋壳强度显著降低(P0.05),钙、磷的代谢率和吸收量差异不显著(P0.05),鸡蛋品质差异不显著(P0.05)。结果提示,夏季鸡舍内温度在27~30℃波动即可显著降低蛋鸡的体增重、平均蛋重和蛋壳品质;而29~35℃不仅显著降低蛋鸡的体增重、产蛋率、平均蛋重以及蛋壳品质,还显著影响鸡蛋的蛋白高度和蛋黄颜色。高温对蛋鸡产蛋性能及蛋白高度和蛋黄颜色的影响可能与降低采食量有关;高温可能直接影响蛋壳的形成,也可能由于降低钙、磷吸收量影响蛋壳品质。     

Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens

1. The objective of the study was to investigate the effect of dietary karaya saponin on cholesterol deposition in laying hens. 2. A total of 40 Boris Brown hens were randomly assigned at 20 weeks of age to 4 treatment groups and fed on diets supplemented with 0 (control), 25, 50 or 75 mg/kg karaya saponin for an 8-week experimental period. 3. After 8 weeks of dietary supplementation, karaya-saponin-treated groups had significantly lower serum cholesterol (23·0%) and triglycerides but increased high density lipoproteins cholesterol concentration than controls, irrespective of karaya saponin content in the diet. Egg yolk cholesterol and triglycerides were also significantly reduced by dietary karaya saponin. Hepatic cholesterol and triglycerides were significantly reduced by karaya saponin but bile acids concentration in the faeces and liver were significantly increased by karaya saponin. The concentrations of oleic, linoleic and linolenic acids in the yolk were greater in hens receiving karaya saponin than in controls. Karaya saponin significantly increased egg production, feed efficiency and yolk colour compared with controls. Karaya saponin tended to increase egg weight, feed consumption, Haugh units, albumen weight and yolk index. 4. In conclusion, karaya saponin is a potential agent for reducing yolk cholesterol concentration together with an overall increase of production performance and improvement in egg quality.