添喂复合微量元素对伊犁夏牧场放牧绵羊消化代谢的影响

摘要

在伊犁夏牧场分别选取中国美利奴(新疆型)成年母羊40只(分成4组,每组10只,实验1)和成年公羊20只(分成2组,每组10只,实验2),在放牧条件下添喂含有铁、铜、锰、锌、硒的复合微量元素添加剂60 d.在实验1研究对绵羊血液微量元素含量和体增重的影响,在实验2研究对绵羊自由采食、消化代谢、血液微量元素含量和体增重的影响,以阐明伊犁夏牧场放牧绵羊的微量元素营养状况.结果表明,在实验1,分别添喂营养标准量33％,66％和100％的添加剂,绵羊血液铁含量分别增加9.90％,8.53％和8.54％,铜含量分别增加2.16％,2.14％和3.07％,锰含量分别增加4.83％,－2.01％和－2.01％,锌含量分别增加11.96％(P ＜0.05),8.40％和9.00％,硒含量分别增加48.14％(P ＜0.01),46.24％(P ＜0.01)和75.40％(P ＜0.01),日增重分别增加36.62％,19.66％和102.71％(P ＜0.01).在实验2,添喂营养标准量100％的添加剂,对绵羊自由采食量无显著影响,但干物质、有机物、粗蛋白、纤维素和半纤维素的表观消化率分别提高9.7％(P ＞0.05),10.5％(P ＜0.05),7.3％(P ＜0.05),18.2％(P ＜0.01)和29.1％(P ＜0.01),氮保留和体增重分别增加8.5％和49.2％(P ＜0.01),血液铁、铜、锰、锌和硒含量分别增加7.09％,30.37％(P ＜0.01),0,22.48％(P ＜0.01)和111.57％(P ＜0.01),铁、铜、锰、锌和硒保留量分别增加9.5％(P ＞0.05),41.5％(P ＜0.01),29.2％(P ＜0.01),79.2％(P ＜0.01)和4630.3％(P ＜0.01).在本研究5种元素中,锰的吸收率最低(＜1.7％),硒的最高(＞34.0％)；添喂复合微量元素大幅度提高绵羊血液硒含量,提高铁、锌、铜含量,但对锰的影响不显著；添喂复合微量元素不影响放牧绵羊自由采食量,但提高牧草的消化率和体增重.本研究表明,在伊犁夏牧场添喂复合微量元素可提高放牧绵羊消化率,改善绵羊营养；建议添喂的硒、铜、锌量分别为0.5,＞15,＞45 mg/d,而铁、锰不需添喂.%On Yili summer pastures,the 40 of ewe (in Experiment 1,divided into 4 groups,each n =10 ) and 20 of ram (in Experiment 2,divided into 2 groups,each n =10)of Chinese Merino (Xinjiang Type) were selected and supplemented with complex trace element additives (CTEA)containing Fe,Cu,Mn,Zn and Se for 60 days,to study the nutritional status of trace element of sheep on Yili summer pastures.In ex-periment 1 the effect of supplement on the contents of trace elements in blood (CTEB)and daily body weight gain (DBWG)and in Experiment 2 the effect of supplement on the voluntary intake,digestion and metabolism,CTEB,BG were studied.The results show that in Experiment 1 when CTEA was supplemen-ted by 33%,66% and 100% of nutritional standard,the Fe contents of sheep blood were increased by 9.90%,8.53% and 8.54% respectively,the Cu contents were increased by 2.1 6%,2.14% and 3.07% respec-tively,the Mn contents were increased by 4.83%,-2.01% and -2.01% respectively,the Zn contents were increased by 1 1.96% (P 0.05 ),10.5% (P 0.05),41.5% (P 34%);the supplement of CTEA greatly increased,the content of Se in the blood of sheep,that of Fe,Zn,Cu increased,but did not significantly affect the blood content of Mn;the supplement of CTEA did not affect the voluntary intake of sheep on pasture,but the digestibility of herbage and DBWG increased.It is concluded that the supplement of CTEA could increase the digestibili-ty of pastured sheep,improve the nutritional status of sheep;the suggested supplements of Se,Cu,Zn were 0.5,>15,>45 mg/d,and there was no need for the supplements of Fe and Mn.