Effects Of Phytase On Growth Performance And Utilization Of Nutrients For Growing Pigs

Effect of supplementary phytase in growing-pigs diet was evaluated in this paper. Firstly,the effect of two kinds of phytase(Aspergillus niger phytase,Escherichia coli phytase) supplement to growing-pigs diet on performance and utilization of nutrients was compared,then Escherichia coli phytase was used to assess the effect of different levels microbial phytase added to low-P diets on growth performance and utilization of nutrients for growing pigs.1,Effects of different kinds of phytase supplemented in diets on growth performance and nutrient availability of growing pigs.In the experiment 54 growing pigs were conducted to study the effects of two kinds of phytase substitute inorganic phosphorus in diet on the growth performance, nutrient availability,serum biochemical parameters and excretion of feces P and N. There were 3 treatments,each treatment had 3 replicates with 6 pigs per pen.The addition of phytase in low-P diet improved ADG,reduced F/G,what is more, supplement Escherichia coli phytase to diet had significantly improved the growth performance of pigs.Adding phytase in low-P diet improved the apparent digestibility of DM,CP,CF,EE,Ca,P,GE respectively(P＜0.05).The excretion of feces P and feces N was decreased by fed low-P with adding Phytase diet.The concentration of total protein,globulin,P were improved by adding phytase(P＜0.05),the concentration of BUN,serum Ca was decreased by fed diets with adding phytase(P＜0.05).The enzymatic activity of alkaline phosphatase in serum was not affected and the concentration of serum sugar was decreased by adding Aspergillus niger phytase;the enzymatic activity of alkaline phosphatase in serum was decreased(P＜0.05) by adding Escherichia coli phytase.2,Effects of phytase supplemented in low-P diets on growth performance and nutrient availability of growing pigs. (1),The growth performance significantly improved by added 300U～500U/kg phytase to low-P dietⅠ(TP,0.48%),and there had a tendency to improve growth performance by adding 500U/kg phytase to low-P dietⅡ(TP,0.48%),but adding 300U/kg phytase in low-P dietⅡwas not enough to improve growth performance of pigs.(2),Adding phytase in low-P diet improved apparent digestibility of DM,CP,Ca,P,GE(P＜0.05),respectively.Also the excretion of feces P,N was significantly decreased by fed low-P with adding phytase diet.The concentration of serum total protein,globulin,P were tended to increase in pigs fed low-P with adding phytase diet,but concentration of serum Ca,BUN and the enzymatic activity of alkaline phosphatase in serum were tended to decrease.