本试验通过饲养试验、消化代谢试验以及微生物区系检测,研究不同来源植酸酶对猪生长性能、营养物质表观消化率及肠道微生物区系的影响。选用日龄相差不超过3 d的"杜×长×大"断奶仔猪144头,按照遗传背景相同、体重相近、性别比例一致的原则随机分为4个组,每组设6个重复,每重复6头仔猪。对照组饲喂基础饲粮,试验1、2、3组饲喂在基础饲粮的基础上降低1/3磷酸氢钙添加量的饲粮,并分别添加500 U/kg微生物来源植酸酶、500 U/kg转植酸酶基因玉米来源植酸酶和5 000 U/kg转植酸酶基因玉米来源植酸酶等比例替代玉米。试验期为90 d。结果表明:各试验组平均日增重均有高于对照组的趋势(P>0.05),以试验3组最高,较对照组提高了1.85%;各组间平均日采食量未见显著差异(P>0.05);与对照组相比,试验3组料重比降低了1.49%(P>0.05)。与对照组相比,各试验组能量、粗蛋白质、粗脂肪表观消化率未见显著变化(P>0.05),试验3组磷表观消化率显著提高(P<0.05),而钙表观消化率呈提高趋势(P>0.05)。各组间回肠和盲肠中总需氧菌、总厌氧菌、大肠杆菌、乳酸菌、双歧杆菌数量均没有显著性变化(P>0.05)。本试验条件下,在猪饲粮中使用转植酸酶基因玉米来源植酸酶与微生物来源植酸酶效果相当,如适量增加转植酸酶基因玉米来源植酸酶用量,效果更明显,不仅不影响生长性能,且可减少磷酸氢钙的使用和氮磷的排放,故在生产实践中可以替代微生物来源植酸酶。

In this experiment, the effects of different sources of phytase on growth performance, apparent digestibility of nutrients, and intestinal microflora of pigs were studied using feeding trial, digestion and metabolism trial and microflora test. A total of 144 weaner piglets (Duroc×Landrace×Large White) with the age difference less than 3 days, the same genetic background, similar body weight, and the same sex ratio were randomly divided into 4 groups with 6 replicates in each group and 6 piglets per replicate. The control group was fed a basal diet and experimental groups 1, 2 and 3 were fed the basal diet reduced 1/3 calcium monohydrogen phosphate supplemental level and added 500 (microbial source), 500 (tran-phytase-gene corn source), and 5 000 U/kg (tran-phytase-gene corn source) phytase to replace corn with an equal ratio, respectively. The experiment lasted for 90 days. The results showed as follows: compared with the control group, the average daily gain of experimental groups was higher (P>0.05) and that of experimental group 3 was the highest, and was increased by 1.85%; the average daily feed intake did not show a difference among all the groups; compared with the control group, the feed/gain of experimental group 3 was decreased by 1.49% (P>0.05). Compared with the control group, the apparent digestibility of dietary energy, crude protein, and crude fat of experimental groups did not significantly change (P>0.05), the phosphorus apparent digestibility of experimental group 3 was significantly increased (P<0.05) and the calcium apparent digestibility showed an improving trend (P>0.05). The phytase had no effect on the number of total aerobe, total anaerobe, Escherichia coli, Lactobacillus, and Bifidobacterium in ileum and cecum among all the groups (P>0.05). The results indicate that tran-phytase-gene corn source phytase and microbial source phytase in the diet of pigs have the same effect. With an increase in the dosage of tran-phytase-gene corn source phytase, the effect is more obvious. It has no negative effect on the growth performance and can reduce the calcium monohydrogen phosphate used amount and nitrogen and phosphorus emissions. Therefore, tran-phytase-gene corn source phytase can replace microbial source phytase in production practice.