共查询到13条相似文献,搜索用时 15 毫秒
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试验选用1 600只生产性能相同、体况良好的33周龄罗曼蛋种鸡,随机分为4组,在总蛋白质含量相同和满足必需氨基酸需要量的情况下,用价格较低的蛋白饲料取代蛋鸡日粮中豆粕,研究氨基酸平衡的低豆粕日粮对蛋种鸡生产性能和蛋品质的影响。结果表明:氨基酸平衡的低豆粕日粮对蛋鸡产蛋率、种蛋合格率、健雏率、蛋形指数、蛋比重、蛋壳厚度、哈氏单位等指标无显著影响(P>0.05),但当日粮中的豆粕含量降低8~15个百分点时,蛋种鸡的日平均蛋重、日采食量、受精率、孵化率等显著低于正常豆粕日粮(P<0.05),而考虑综合因素日粮中的豆粕含量降低8个百分点的第1组,与正常豆粕日粮相比,差异不显著(P>0.05),而且能降低饲料成本,可以提高蛋鸡养殖效益,具有实际意义。 相似文献
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Rare earth element‐enriched yeast improved egg production and egg quality in laying hens in the late period of peak egg production 下载免费PDF全文
L. Cai C. M. Nyachoti J. D. Hancock J. Y. Lee Y. H. Kim D. H. Lee I. H. Kim 《Journal of animal physiology and animal nutrition》2016,100(3):492-498
The objective of this study was to determine the effects of rare earth element‐enriched yeast (RY) on egg production, coefficient of total tract apparent digestibility (CTTAD), egg quality, excreta gas emission and excreta microbiota of laying hens. A total of 216 ISA brown laying hens of 52 weeks of age were used in a 5‐week feeding trial and data were collected every week. Birds were randomly allotted to three dietary treatments each with six replicates and 12 hens per replicate. Each cage (38 cm width × 50 cm length × 40 cm height) contained one hen. Treatments consisted of corn–soya bean meal‐based diet supplemented with 0, 500 or 1000 mg/kg of RY. From weeks 55 to 56, inclusion of RY linearly increased (p < 0.05) egg production. The CTTAD of nitrogen was increased (linear, p < 0.05) with increasing dietary level of RY. In week 55, yolk height and Haugh units were increased linearly (p < 0.05) with increasing dietary RY content. However, no significant effects were observed in terms of excreta emissions and excreta microbiota in laying hens. In conclusion, dietary supplementation with RY improved egg production and CTTAD of nitrogen and slightly improved egg quality in laying hens of the late period of peak egg production. 相似文献
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《The Journal of Applied Poultry Research》2009,18(2):203-209
Organic acids have been widely used as feed additives to replace antibiotics in livestock feeds. Data on the use of phenyllactic acid (PLA) are lacking. The effects of PLA on production performance, egg quality parameters, and blood characteristics in laying hens were studied in a 35-d experiment. A total of 240 ISA Brown 36-wk-old layers were divided into the following 4 treatments: 1) control (basal diet), 2) control + 0.1% PLA, 3) control + 0.2% PLA, and 4) control + 0.3% PLA. Although supplementing the diet with PLA did not affect ADFI and FE, it linearly improved egg production rate, eggshell breaking strength, and Haugh units. Egg weight, eggshell thickness, and egg yolk color were not significantly altered by supplementing the diet with PLA. White blood cell, red blood cell, total protein, and albumin concentrations were higher in the control + 0.1% PLA and control treatment groups (P < 0.05), whereas the groups fed the control + 0.2% PLA and control + 0.3% PLA diets had greater (P < 0.05) lymphocyte concentrations. In conclusion, PLA may exert some positive effects to the immune system and egg production over the short term. It may be beneficial to supplement the diets of laying hens with PLA in the absence of antibiotics. This experiment involved a small experimental sample and a short time, so the beneficial effects of PLA should be studied further in commercial farms over the long term. 相似文献
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Impact of supplementing diets with propolis on productive performance,egg quality traits and some haematological variables of laying hens 下载免费PDF全文
A. A. A. Abdel‐Kareem T. M. El‐Sheikh 《Journal of animal physiology and animal nutrition》2017,101(3):441-448
One hundred and twenty eight, 28‐weeks‐old Lohmann LSL hybrid layers were used in this experiment, which lasted 12 weeks to investigate the effect of propolis supplementation on the productive performance, egg quality traits and haematological variables of laying hens. All hens were randomly classified into four equal experimental groups, eight replicates (4 birds/each). Hens in group 1 were fed on a commercial diet and considered as control group, while those in groups 2, 3 and 4 were fed on the same commercial diet and supplemented with 250, 500 and 1000 mg propolis/kg diet. The obtained results revealed that daily feed consumption/hen increased insignificantly with increasing propolis level than that of the control group. Regarding the means of egg mass and egg production rate, it was observed that the laying hens fed diets containing 250 and 1000 mg propolis/kg significantly (p < 0.05) produced more and heaver egg in comparison with control group. External egg quality traits have not affected with increasing the level of propolis, while eggshell weight was significantly (p < 0.05) increased. The internal egg quality traits except albumen and yolk percentages increased significantly (p < 0.05) with increasing propolis level for treated hens as compared to those in the control. Concerning the haematological parameters, the results showed that the levels of total protein and globulin increased significantly with increasing propolis level, while cholesterol and liver enzymes were significantly decreased (p < 0.05). Heterophils count of hens in the treated groups significantly decreased, whereas the lymphocyte count significantly increased, resulting in a decreased H/L ratio than that of the control group. Thus, it could be concluded that the supplementation of 250 mg propolis/kg diet is highly recommended to improving egg production, blood constituent and haematological parameters of the commercial laying hens. 相似文献
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