1～40日龄羔羊哺乳量、开食料采食量和体增重研究

Studies on the Sucked Milk,Starter Feed Intake and Body Weight Gain of 1-40 Day's Lambs

【目的】研究在自由采食条件下1-40日龄羔羊的吮乳量、开食料采食量和消化率、及对日增重的影响。【方法】选取新生双羔或三羔小尾寒羊羔羊16只,平均体重（3.02±0.23）kg,公母各半,分为四组（每组n=4,1组：公羔,21日龄断奶;2组：母羔,21日龄断奶;3组：公羔,28日龄断奶;4组：母羔,28日龄断奶）,使用吮乳前后称体重、PEG标记羔羊粪等方法。【结果】小尾寒羊母羊的泌乳高峰为产后5-12 d,之后则逐渐下降,乳的干物质含量在产后一周内高于30%,之后则逐渐降低和趋于稳定。然而,母羊的泌乳量（或羔羊吮乳量）差异较大。1-28日龄多羔小尾寒羊的平均吮乳量为0.65 kg/羔/日,为单羔的61.4%,从母乳获得的营养较少。1周龄羔羊对开食料即有较高的消化率（约60%）,之后则基本稳定。【结论】羔羊随日龄对开食料消化能力的提高主要表现为采食量的提高而不是消化率。在吮母乳和自由采食开食料条件下羔羊约28日龄时断奶较好,如果在21日龄断奶则会出现体重下降。

【Objective】To study the sucked milk,starter feed intake and its digestibility,and their effect on daily body weight gain of 1- 40 day＇s lambs in the condition of voluntary intake.【Method】16 of newborn Small Tail Han twin or triple lambs,with average body weight of 3. 02 ± 0. 23 Kg,were selected（ half for male and female）,by the methods of weighting body weight before and after sucking,PEG marking feces of lamb.The lambs were divided into 4 groups（ each n = 4） ： group 1： male,weaning at 21 day＇s; group 2： female,weaning at 21 day＇s; group 3： male,weaning at 25 day＇s; group 4： female,weaning at 25 day＇s.【Result】The results showed that the lactating peak of Small Tail Han ewe was in 5- 12 days after partum,and was gradually decreased after that. The content of dry matter of milk was 30% higher in the first week after partum,and then was gradually decreased and tended to be stable. However,the lactating amount of ewes（ or the amount sucked by lambs） was quite different. The average sucking amount by multiple lambs of 1- 28 day＇s old was 0. 65 kg/ lamb / day,only being 61. 4% of single lamb ＇s,therefore getting less nutrients from ewes. The lambs of 1week＇s old had higher digestibility on starter feed（ about 60%）,and was basically stable after that.【Conclusion】The increased digestive ability of lambs on starter feed was found in the enhance of intake,rather than its digestibility. The convenient weaning time for lamb was at 28 day＇s old,if they were weaned at 21 day＇s old,the lambs would lose their body weight.