Department of Animal Nutrition, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, 37 Kshudiram Bose Sarani, Kolkata 700037, India.
Biol Trace Elem Res. 2010 Nov;137(2):190-205. doi: 10.1007/s12011-009-8570-z. Epub 2009 Nov 28.
Supplementation of broiler diets with copper, manganese, and zinc at levels higher than that stipulated by the National Research Council 1994 reportedly improved live weight, feed conversion, and cured leg abnormality supposedly caused by inadequate intake of Mn and Zn. The objective of the study was to ascertain the effects of plethoric supplementation of copper (Cu), manganese (Mn), and zinc (Zn) on performance and metabolic responses in broiler chickens. The study also aimed to discriminate the responses of the birds when the mineral elements were supplemented either in an inorganic or in an organic form. Cobb 400 broiler chickens (1-day old, n = 300) were assigned to three dietary treatments each containing nine replicates with ten birds for 39 days. The treatments included a control in which the diet was devoid of supplemental trace elements and treatments supplemented with an inorganic trace element premix (ITM) and supplemented with a combination of the inorganic and an organic trace element premix (OTM). The ITM contained (per kilogram) copper, 15 g; iron, 90 g; manganese, 90 g; zinc, 80 g (all as sulfated salts); iodine (as potassium iodide), 2 g; and selenium (as sodium selenite), 0.3 g. The OTM on the other hand, contained copper, 2.5 g; iron, 15 g; manganese, 15 g; zinc, 13.33 g; and chromium, 0.226 g (all as protein chelates). Plethoric supplementation of trace elements improved live weight gain and feed/gain ratio (p < 0.05). Leg abnormality developed in the 16% of the control group of birds but not in the supplemented group. Metabolizability of dry matter, organic matter, and protein was higher (p < 0.01) in the ITM and OTM groups. Excretion of Cu, Fe, and Zn decreased (p < 0.1) due to supplementation of the trace elements leading to increased apparent absorption of the said mineral elements (p < 0.01). Concentration of the concerned trace elements in serum, liver, and composite muscle samples was higher (p < 0.05) in the ITM and OTM dietary groups indicating an increased deposition of the said mineral elements due to supplementation. Although the study revealed subtle difference between the inorganic and organic mineral premixes with regards to the parameters mentioned above, it became apparent that it is possible to reduce excretion of these trace elements by a judicious escalation in the level of supplementation. The results of the present investigation further revealed that the trace mineral requirement of broiler chickens suggested by the National Research Council may not be optimum to support the maximum growth potential of the high yielding strains, and it is reasonable to consider a review of the current NRC recommendations to meet the needs of the modern birds.
据报道，在肉鸡日粮中添加铜、锰和锌，其水平高于 1994 年全国研究委员会规定的水平，可改善活重、饲料转化率和治疗因锰和锌摄入不足引起的腿部异常。本研究的目的是确定过量补充铜（Cu）、锰（Mn）和锌（Zn）对肉鸡生长性能和代谢反应的影响。本研究还旨在区分当矿物质元素以无机或有机形式补充时，鸟类的反应。将 300 只科布 400 只肉鸡（1 日龄，n=300）分为 3 种日粮处理，每种处理包含 9 个重复，每个重复 10 只，饲养 39 天。处理包括对照，其中日粮不含补充微量元素；处理 1 用无机微量元素预混料（ITM）补充；处理 2 用无机和有机微量元素预混料（OTM）组合补充。ITM 含有（每千克）铜 15 克；铁 90 克；锰 90 克；锌 80 克（均为硫酸盐）；碘（碘化钾）2 克；硒（亚硒酸钠）0.3 克。另一方面，OTM 含有铜 2.5 克；铁 15 克；锰 15 克；锌 13.33 克；铬 0.226 克（均为蛋白质螯合物）。微量元素的过量补充提高了活重和饲料/增重比（p<0.05）。在对照组的 16%的鸟类中出现腿部异常，但在补充组中没有出现。干物质、有机物和蛋白质的可利用率在 ITM 和 OTM 组中更高（p<0.01）。由于补充微量元素，铜、铁和锌的排泄减少（p<0.1），导致所述矿物质元素的表观吸收增加（p<0.01）。血清、肝脏和复合肌肉样品中与上述元素相关的痕量元素浓度在 ITM 和 OTM 日粮组中更高（p<0.05），表明由于补充，所述矿物质元素的沉积增加。尽管该研究揭示了无机和有机矿物预混料之间在上述参数方面的细微差异，但很明显，通过明智地提高补充水平，可以减少这些痕量元素的排泄。本研究的结果进一步表明，全国研究委员会建议的肉鸡微量元素需求可能不能满足高产品系最大生长潜力的需要，有理由考虑审查当前的 NRC 建议，以满足现代鸟类的需要。
