内蒙古牧区察哈尔羔羊饲粮钙磷适宜水平研究

本试验采用4个不同钙磷水平的饲粮饲喂断奶后察哈尔羔羊,研究钙磷对断奶羔羊生长、钙磷营养消化代谢和排放量、骨骼的影响。选取70日龄健康、体重(16.27±3.33) kg断奶察哈尔羔羊120只(公母各半),随机分成4个组,每组30个重复,每个重复1只羊,分别饲喂4种饲粮,其钙磷含量分别为:Ⅰ组,0.49%、0.28%;Ⅱ组,0.55%、0.32%;Ⅲ组,0.64%、0.47%;Ⅳ组,0.87%、0.70%。饲养试验期65 d,其后,每组选6只羔羊(公母各半),全收粪法进行消化代谢试验。试验结果:1)饲粮钙磷水平对断奶羔羊平均日增重、体尺、干物质采食量和饲粮转化率影响皆不显著(P>0.05);2)血清钙含量Ⅳ组显著高于其他3组,血清碱性磷酸酶Ⅰ组显著高于其他3组(P<0.05);3)Ⅰ组钙表观消化率显著高于其他3组(P<0.05),随饲粮钙磷水平升高羔羊钙磷排放量增加(P<0.05);4)Ⅳ组胫骨灰分含量显著高于Ⅰ组(P<0.05),Ⅰ组跖骨灰分含量显著低于Ⅲ、Ⅳ组(P<0.05),胫骨磷含量Ⅳ组显著高于其他3组(P<0.05);5)冬春季节改变羔羊饲喂模式增加了内蒙古地区草原生态系统中钙磷的输入。综上所述,饲粮钙磷水平升高降低了断奶羔羊的钙表观消化率,显著增加了钙磷的排放量,提高了羔羊骨骼钙磷沉积。在本试验条件下,饲粮钙磷含量分别为0.49%、0.28%,内蒙古地区冬春季断奶羔羊即可获得较好的生长性能。

Effect of dietary calcium and phosphorus on growth,blood metabolites,and digestion in Chahaer lambs in Inner Mongolia

The present study was conducted to investigate the effect of dietary calcium (Ca) and phosphorus (P) on growth performance,digestibility and output of Ca and P,and bone characteristics of weaned Chahaer lambs.120 weaned Chahaer lambs [liveweight (16.3+3.3) kg;age 70 days] were randomly assigned into 4 groups:Ca and P levels in the diets of group Ⅰ,Ⅱ,Ⅲ and Ⅳ were 0.49％ and 0.28％,0.55％ and 0.32℃,0.64℃ and 0.47℃ and 0.87％ and 0.70％,respectively.The feeding trial lasted for 65 days;6 lambs (3 male and 3 female) were randomly selected to be slaughtered from every group to collect data on Ca and P metabolism and digestion.The results showed that dietary Ca and P levels had no effect on liveweight gain,dry matter intake and feed conversion (P＞0.05).Blood serum Ca content in group Ⅳ was the highest among the four groups (P＜0.05),whereas serum alkaline phosphatase in group Ⅰ was higher than other three groups (P＜0.05).The apparent digestibility of Ca in group Ⅰ was significantly higher than other three groups (P＜0.05).Ca and P outputs were significantly increased with increasing dietary Ca and P levels (P＜0.05).The tibia ash and P content from lambs in group Ⅳ was significantly higher than that in group Ⅰ (P＜0.05) and the metatarsal ash content in group Ⅰ was lower than those in group Ⅲ and Ⅳ (P＜0.05).Increased Ca and P in the diet of lambs increased Ca and P input into the grassland during winter and spring.It was concluded that increased Ca and P levels in the diet of weaned lambs reduced the apparent digestibility of Ca but significantly increased the Ca and P content in the feces and bones.Optimal levels of Ca and P in the diet of weaned Chahaer lambs was 0.49％ and 0.28％ respectively.