30～60kg生长猪磷需要量研究

本试验旨在研究饲粮磷水平对30 ～60kg生长猪生长性能、血清生化指标及胫骨性能的影响,探讨饲粮中磷的适宜需要量.试验采用单因子完全随机设计,将30头体重( 32.12±0.49) kg的“杜×长×大”生长猪随机分为5组,每组6个重复,每个重复1头猪,各组分别饲喂磷水平为0.38％(对照组)、0.43％、0.48％、0.53％、0.58％的玉米-豆粕型试验饲粮.预试期7d,正试期28 d.结果表明:1)与对照组相比,0.53％磷水平组平均日增重、平均日采食量极显著提高(P＜0.01),料重比极显著降低(P＜0.01)；2)各试验组血清磷含量均极显著高于对照组(P＜0.01),0.53％磷水平组血清钙含量显著低于对照组(P＜0.05),各组血清胰岛素样生长因子-Ⅰ含量差异不显著(P＞0.05)；3)随饲粮磷水平的提高,胫骨长度及胫骨钙、磷含量均呈现先升高再降低的趋势,当饲粮磷水平为0.53％时,各指标达到最大值,但差异不显著(P＞0.05)；0.53％磷水平组胫骨脱脂烘干重显著高于对照组(P＜0.05),其他各组之间差异不显著(P＞0.05).综上所述,在本试验条件下,30 ～ 60 kg生长猪饲粮磷的适宜添加水平为0.53％.

Phosphorus Requirement of Growing Pigs Weighing 30 to 60 kg

This experiment was conducted to study the effects of dietary phosphorus level on growth performance,serum biochemical indices and tibia performance of growing pigs,and to explore the optimal phosphorus level in the diet of growing pigs weighting 30 to 60 kg.A single factorial randomized design was adopted,and thirty crossed pigs(Duroc×Landrace×Yorkshire) with an average bodyweight of(32.12±0.49) kg were randomly allotted into 5 groups with 6 replicates per group and 1 pig per replicate.Pigs were fed corn-soybean experimental diets supplemented with 0.38%(control group),0.43%,0.48%,0.53% and 0.58% phosphorus,respectively.The adjustment period lasted for 7 days,and the experimental period lasted for 28 days.The results showed as follows: 1)compared with the control group,the average daily gain,average daily feed intake in 0.53% group were significantly increased(P<0.01),however,the feed/gain in 0.53% group was significantly decreased(P<0.01).2) The serum phosphorus content in experimental groups was significantly higher than that in control group(P<0.01),and the serum calcium content in 0.53% group was significantly lower than that in control group(P<0.05).The insulin-like growth factor Ⅰ(IGF-Ⅰ) content was not affected by dietary phosphorus level(P>0.05).3) The length of tibia,the content of calcium and phosphorus of tibia were increased at first and decreased subsequently with the dietary phosphorus increasing,and they got the highest values in 0.53% group(P>0.05).The dry fat-free weight of tibia in 0.53% group was significantly higher than that in control group(P<0.05),and there was no significant difference among other groups(P>0.05).In conclusion,the optimal phosphorus requirement of growing pigs weighing 30 to 60 kg is 0.53% under the conditions of this experiment.