Effects Of Phytase On The Growth Performance, Nutrients Utilization And Serum Biochemical Parameters In Growing-finishing Pigs

The purpose of this work was to evaluate the effects of different phytase on growth performance, nutrients utilization, serum biochemical parameters in growing-finishing pigs. It was aimed to provide some scientific information for swine production. Total of336weanned piglets (DurocxLandracexYorkshire)were randomly divided into7treatment groups, consisting6replicates of8pigs(equally divided between male and female), respectively. The dietary treatments were:PC (control diet, no phytase); NC (low phosphorus, no phytase); T1(NC+500U/kg tunicatus phytase); T2(NC+1000U/kg tunicatus phytase); T3(NC+10000U/kg tunicatus phytase); T4(NC+500U/kg powdery phytase); T5(NC+500U/kg granular phytase). Trial period was100days. The period was divided into3periods:Ⅰ (60～89d), Ⅱ (90～117) and Ⅲ(118～160).1. Effects of different phytase on the growth performance, immune performance, analysis of economic benefits in growing-finishing pigs.The results showed:(1) Adding phytase with different doses and dosage-form, growth performance of group T1is highest, the second one is group T5. Period Ⅰ, growth performance of all groups was not significantly different (P>0.05). Period Ⅱ, ADG of group T1was significantly higher than the other groups (P<0.05). F:G of groups T1and T5was significantly lower than the control groups (P<0.05). Period Ⅲ, ADG of group T1is highest, which was significantly higher than the control groups (P<0.01). F:G of group T1, T4and T5, were significantly lower than the control groups(P<0.01). In the whole stage, ADG of the group T1was significantly higher than the controls (P<0.01), F:G of group T1and T2was significantly lower than the control groups (P<0.01);(2) There was a trend of decrease in diarrhea rate and diarrhea index in the whole stage of growing-finishing pigs, adding different phytase, but there were no statistal differences among all the groups (P>0.05).(3) The cost of group T1is lowest, which was reduced by2.58%and4.09%respectively, compared with the control groups. All in all, group T1showed the best economic benefits.2. Effects of different phytase on common nutrients utilization, content of mineral element in feces and amino acid digestibility in growing-finishing pigs.The result showed:(1) During the period I, there was a rising tendency on the digestibility of common nutrients with phytase supplemention, but there was no significant distinction (P>0.05). And during Ⅱ, there was the same effect on the nutrient. The group of T1had the best effectiveness except CP. The GE, DM and ASH had a significant distinction (P<0.05) to the other groups (except group T5); the group T2had the highest digestibility of CP, and had a significant distinction (P<0.05) to the other groups. During the period III, the group of T1had the highest digestibility of GE, DM and ASH and had a significant distinction (P<0.01) to the other groups (except group T5and T2). Group T2had the the highest digestibility of CP and also had a significant distinction (P<0.01) to the other groups(P<0.01).(2) During growing-finish period, every experiment group had a rising tendency on the digestibility of Ca, but there was no significant distinction(.P>0.05). During the period I, there was a degrading tendency on the contents of Fe and Mn in faece, but no significant distinction(P>0.05). And so was mineral element in faece during Ⅱ.During the period Ⅱ, the group of T1had the highest digestibility of P and had a significant distinction (P<.05) to the other groups (except group T5). Group T1showed the lowest content Cu and Zn in faece and a significant distinction (P<0.01) to the other groups. During the period Ⅲ, the digestibility of P had a significant distinction (P<0.01) to control groups and T4. Group T1had the lowest content Cu and had a a significant distinction (P<0.01) to the other groups (except groupT5).(3) During the period Ⅰ,the digestibility of Lys and Cys of T2had a significant distinction (P<0.05) to the other groups,and so did the digestibility of Met, Val, Ile and Ala. However there was no regularity on the other amino acid (AA), so was AA during the period Ⅱ. During the period Ⅲ, there was the highest digestibility of Lys、Met、Thr and Ile, and had a significant distinction (P<0.05) to control group, but there was no regularity on the other AA.3. Effects of different phytase on activity of digestive enzyme, contents of calcium, phosphorus and immune protein of serum in growing-finishing pigs. The results showed:(1)75d,100d,150d, Amylase(AMS) activity of group T1was highest in all groups of the three periods, then followed by group T5followed. There was an increasing trend on AMS activity in the three stages by adding different phytase, but the difference of all groups were not significant (P>0.05).150d, AMS activity of group T1was significantly higher than the control groups (P<0.05).75d,125d,150d, There was increase trend on lipase(LPS) activity in the three stages, adding different phytase, but the changes of all groups were not significantly different (P>0.05).100d, LPS activity of group T1is higher than the positive control group (P<0.05). Four growth stages, there was depress trend on blood urea nitrogen (BUN) in all stages of growing-finishing, adding different phytase, but the changes of all groups were not significantly different (P>0.05).(2)75d,100d, there was increase trend on contents of serum calcium (Ca) and serum phosphorus (P) in two stages, adding different phytase. Alkaline phosphatase (ALP) activity of group T1of was significantly lower than the control groups (P<0.05).125d, serum phosphorus content in group T1was the highest, which was significantly higher than the negative control group (P<0.05).125d,150d, Ca content and ALP activity of group T1in serum were the best, Group T5was the second, but the differences among the groups were not significant (P>0.05).(3)70d, the effects of group T1were the best. The contents of serum total protein (TP) and serum globulin (GLO) were significantly higher than the other groups (P<0.01).100d, the contents of TP and GLO of group T1in serum were significantly higher than the other groups (except group T5).125d and150d, there was increase trend on contents of TP and albumin (ALB) in two stages, adding different phytase, but the changes of all groups were not significantly different (P>0.05).In summary, supplementation of500U/kg phytase could significantly improve the growth performance, nutrients digestibility, but amino acids digestibility was not apparent in growing-finishing pigs, compared to other treatments. The effect of tunicatus dosage-form phytase showed the best. The second one showed granular dosage-form phytase. The powdery phytase was inferior to the formers.