Panda Arun Kumar, Rao Savaram Venkata Rama, Raju Mantena Venkata Lakshmi Narasimha, Niranjan Matam, Reddy Maddula Ramkoti
Project Directorate on Poultry, Rajendranagar, Hyderabad, India.
Trop Anim Health Prod. 2012 Feb;44(2):293-9. doi: 10.1007/s11250-011-0017-9. Epub 2011 Nov 19.
A study was conducted to evaluate the effect of various concentrations of metabolizable energy (ME) with graded incremental levels of crude protein (CP) and essential amino acids (lysine and methionine) on production performance, egg quality and humoral immune response of Dahlem Red laying hens. Four experimental diets based on maize-soybean meal-deoiled rice bran were prepared. Diet 1 was fed as a control diet containing 2,600 kcal ME/kg, 15% CP, 0.75% Lys and 0.36% Met, and in the other three diets (D2, D3 and D4), concentrations of the above nutrients were increased by 2.5%, 5.0% and 7.5%, respectively. The levels of Ca (3.5%) and available P (0.32) were constant in all the diets. Each diet was offered ad libitum from 28 to 40 weeks of age to eight replicates containing six birds in each replicate. The egg production, egg weight and egg mass (in grams of egg per hen per day) were not affected by increasing the nutrient density up to 7.5% (2,795 kcal ME/kg diet) compared to the control group (2,600 ME/kg diet). However, feed consumption and feed efficiency (in grams of egg per gram of feed) were influenced by the variation in the nutrient density of diets. As the nutrient density increased by 5% (2,730 ME/kg diet), birds consumed significantly (P < 0.001) less feed. The birds in the 7.5% higher density group produced significantly (P < 0.05) higher egg mass per unit feed consumption compared to the control diet. Increasing nutrient density up to 7.5% had no effect on relative weight of albumen, yolk or shell. The Haugh unit, yolk colour and shell thickness were also not affected due to variation in the nutrient density. The humoral immune response measured at 34 and 40 weeks was progressively improved by increasing the nutrient density up to 5%. Increasing the nutrient density beyond 5% in the diet had no further influence on the humoral immune response. Based on the results of the present study, it can be concluded that Dahlem Red laying hens required 2,795 kcal/kg ME, 16% CP, 0.8% lysine and 0.4% methionine for eliciting optimum performance and immune response during 28 to 40 weeks of age.
进行了一项研究，以评估不同浓度的代谢能（ME）以及粗蛋白（CP）和必需氨基酸（赖氨酸和蛋氨酸）的分级增量水平对达勒姆红蛋鸡生产性能、蛋品质和体液免疫反应的影响。制备了四种基于玉米-豆粕-脱油米糠的实验日粮。日粮1作为对照日粮，含有2600千卡ME/千克、15% CP、0.75%赖氨酸和0.36%蛋氨酸，在其他三种日粮（D2、D3和D4）中，上述营养素的浓度分别提高了2.5%、5.0%和7.5%。所有日粮中钙（3.5%）和有效磷（0.32）的水平保持不变。从28周龄到40周龄，将每种日粮随意提供给8个重复组，每组6只鸡。与对照组（2600千卡ME/千克日粮）相比，将营养密度提高至7.5%（2795千卡ME/千克日粮）对产蛋量、蛋重和蛋质量（每只母鸡每天产蛋克数）没有影响。然而，日粮营养密度的变化会影响采食量和饲料效率（每克饲料产蛋克数）。当营养密度提高5%（2730千卡ME/千克日粮）时，鸡的采食量显著减少（P < 0.001）。与对照日粮相比，营养密度高7.5%的组每单位采食量产蛋质量显著提高（P < 0.05）。将营养密度提高至7.5%对蛋白、蛋黄或蛋壳的相对重量没有影响。哈夫单位、蛋黄颜色和蛋壳厚度也不受营养密度变化的影响。在34周龄和40周龄时测定的体液免疫反应随着营养密度提高至5%而逐渐改善。日粮中营养密度超过5%对体液免疫反应没有进一步影响。根据本研究结果，可以得出结论，达勒姆红蛋鸡在28至40周龄期间需要2795千卡/千克ME、16% CP、0.8%赖氨酸和0.4%蛋氨酸以获得最佳生产性能和免疫反应。
