低蛋白质补充氨基酸日粮对哺乳母猪繁殖性能、背膘厚和乳成分的影响

研究旨在探讨低蛋白质补充氨基酸日粮对哺乳母猪繁殖性能、背膘厚和乳成分的影响。选择35头胎次、体重和体况相近的哺乳母猪，采用单因子试验设计，随机分为3个处理，每处理分别为13、11、11头母猪。对照组使用常规日粮，粗蛋白质水平为17.7%，试验Ⅰ、Ⅱ组分别使用低蛋白质补充氨基酸日粮，粗蛋白质水平为15.7%、13.7%，其氨基酸水平与对照组相近，哺乳期21 d。结果表明：①与对照组相比，试验Ⅰ、Ⅱ组21日龄断奶全窝重、哺乳期母猪采食量、仔猪窝采食量及成活率均无显著差异（P>0.05），随着日粮蛋白质水平的降低母猪的失重有所增加，但各处理间差异不显著（P>0.05）；②随着日粮蛋白质水平的降低，母猪背膘损失比例减少，但各处理间差异不显著（P>0.05）；③与对照组相比，试验Ⅱ组的乳品质较好，但无显著差异（P>0.05）。以上结果说明，通过补充氨基酸降低哺乳母猪日粮粗蛋白质水平（由17.7%降至15.7%、13.7%），不会影响母猪及仔猪的生产性能，是节约蛋白质资源的有效措施。

Effect of Low Protein Diet Supplemented with Amino Acids on the Reproductive Performance,Change of Backfat Thickness and Milk Composition of Lactating Sows

The objective of the study were to investigate the effects of low protein diets supplemented with amino acids on the reproductive performance,change of backfat thickness and milk composition of the lactating sows.35 crossbred sows with similar parity,body weight and body conditions were selected and randomly divided into 3 treatments and each treatment had 13,11 and 11 sows,respectively.A single-factor experimental design was used.Pigs in control group were fed conventional commercial diet with CP level of 17.7%,and the pigs in experimental groupⅠand Ⅱ were fed the diets supplemented with amino acids,and their CP level were 15.7% and 13.7%.The amino acid concentrations were the same in all three diets.The lactation length was 21 days.The results showed that:①Compared with control group,the total litter weight at 21 days,feed intake of lactating sows,survival rate and feed intake of piglets in the experimental groups had no significant difference（P>0.05).With the decrease of protein level,sows' body weight loss increased,but the differences were not significant among the treatments（P>0.05).②With the decrease of protein level,the ratio of sows' reduced fat thickness declined,but the differences among the treatments were not significant(P>0.05).③The milk composition of sows in experimental group Ⅱ was better than that in the control group,but the difference was not significant（P>0.05).The results indicated that using the diets with reduced CP level（from 17.7% to 15.7% or 13.7%）and supplemented with amino acids did not affect the performance of sows and piglets,and it would be an effective measure saving protein resource.