Qiu Kai, Chen Zhimin, Chang Wenhuan, Zheng Aijuan, Cai Huiyi, Liu Guohua
The Key Laboratory of Feed Biotechnology of Ministry of Agriculture, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China.
Front Vet Sci. 2023 May 15;10:1132189. doi: 10.3389/fvets.2023.1132189. eCollection 2023.
This study aimed to determine the ideal balance profile of Cu, Fe, Zn, and Mn for broilers of 1-21 days of age via a uniform experimental design. In Experiment 1, 900 1-day-old Arbor Acres male broilers were randomly allotted to 15 dietary treatments with six replicates of 10 birds. A total of 14 experimental diets were formulated with the supplementation of 816, 123160, 4080, and 60120 mg/kg of Cu, Fe, Zn, and Mn, respectively, in the basal diet, according to the uniform design method. The excretion of Cu, Fe, Zn, and Mn in the manure and the broiler performance were determined to build the ideal balance profile of these elements. Experiment 2 was conducted based on the ideal balance profile built in Experiment 1, to test its practicability using 720 broilers with two treatments. The dietary concentrations of Cu, Fe, Zn, and Mn in the control group were 15.19, 203.08, 76.78, and 86.13 mg/kg, respectively. In Experiment 1, the concentrations of Cu, Fe, Zn, and Mn in the diets were 16.96, 166.66, 46.01, and 60.26 mg/kg, respectively, when the average daily gain reached the optimum value. When the dietary concentrations of Cu, Fe, Zn, and Mn were 8.54, 130.66, 38.19, and 64.07 mg/kg, respectively, the total excretion of Cu, Fe, Zn, and Mn got the minimum value. There are corresponding ideal balance profiles for minimum excretion of a certain element. In Experiment 2, the dietary levels of Fe, Zn, and Mn were decreased by 17.93%, 40.08%, and 30.04%, respectively, which had no significant effect on average daily gain, average daily feed intake, and feed gain for 1~21 day-old broilers but markedly decreased the excretion of Cu and Mn and total excretion. It was concluded that there is a dilemma between growth performance and mineral excretion. Although dietary levels of Cu, Fe, Zn, and Mn supporting optimal growth are higher than those for minimizing mineral excretion, supplementing too many trace elements in the diets of broilers is unnecessary.
本研究旨在通过均匀试验设计确定1至21日龄肉鸡铜、铁、锌和锰的理想平衡模式。在试验1中，将900只1日龄爱拔益加雄性肉鸡随机分为15种日粮处理，每组10只，重复6次。根据均匀设计方法，在基础日粮中分别添加816、123160、4080和60120 mg/kg的铜、铁、锌和锰，共配制14种试验日粮。测定粪便中铜、铁、锌和锰的排泄量以及肉鸡的生产性能，以建立这些元素的理想平衡模式。试验2基于试验1建立的理想平衡模式进行，用720只肉鸡分两种处理来检验其可行性。对照组日粮中铜、铁、锌和锰的浓度分别为15.19、203.08、76.78和86.13 mg/kg。在试验1中，当日均增重达到最佳值时，日粮中铜、铁、锌和锰的浓度分别为16.96、166.66、46.01和60.26 mg/kg。当日粮中铜、铁、锌和锰的浓度分别为8.54、130.66、38.19和64.07 mg/kg时，铜、铁、锌和锰的总排泄量达到最小值。对于某一元素的最低排泄量存在相应的理想平衡模式。在试验2中，日粮中铁、锌和锰的水平分别降低了17.93%、40.08%和30.04%，这对1至21日龄肉鸡的日均增重、日均采食量和料重比没有显著影响，但显著降低了铜和锰的排泄量以及总排泄量。得出的结论是，生长性能和矿物质排泄之间存在两难困境。虽然支持最佳生长的日粮中铜、铁、锌和锰的水平高于使矿物质排泄量最小化的水平，但在肉鸡日粮中添加过多微量元素是不必要的。
