Study On The Enzymatic Characteristics Of High Temperature Phytase And Its Application In Theproduction Of Yellow-feathered Broilers

Phytase is widely used in feed production.The enzymatic characteristics and application effects of phytase from different sources are different.This study chooses shandong longkete enzyme preparation co.,LTD.,the introduction of the latest scientific research achievements of strains,USES the advanced modern biological fermentation technology and post-processing technology,refined by liquid submerged fermentation extract of aspergillus Niger phytase production(super heat-resistant type),studying the characteristics of some of its enzymology,explore the super heat-resistant phytase in NDV can be isolated from the dead broilers diet effect,the application of feed production of forage super heat resistance provides the theory basis for the use of phytase,this study the following two tests are carried out.Test 1: in order to explore the enzymatic characteristics of the new type of super thermo-resistant phytase,this study compared and analyzed the activity changes of super thermo-resistant phytase at different temperatures and pH values.Results show that the active along with the change of pH value and temperature is parabolic,respectively,at about 80 ℃ and pH value of 2.5 when the highest enzyme activity;After 85 ℃ treatment remains 91.2% relative enzyme activity,after more than 90 ℃ high temperature processing,loss of enzyme activity is larger(39.5%)of the relative enzyme activity;The relative enzyme activity remained at 89.4% after pH 2 treatment.It can be seen that the super temperature phytase has strong tolerance to acid and high temperature environment,which is more suitable for the application of feed production(high-temperature granulation)and livestock and poultry production(acid environment of gastrointestinal tract).Experiment 2: in order to investigate the effect of super temperature phytase on the growth performance of yellow-feather broilers and the mechanism of action,528 broilers of healthy yellow-feather broilers at the age of 1 day were randomly divided into 8 groups with 6 replicates in each group and 11 feathers in each replicate.Eight diets were designed.The available phosphorus levels of the first four diets were 0.45%,0.38%,0.31%,and 0.24%,respectively.The remaining four diets added 500,750,1000,and 10000FTU/kg phytase into the basic diets with available phosphorus of 0.24%.The trial period was 28 days.The results showed that dietary available phosphorus level was decreased,ADG was significantly decreased(P<0.01),and feed to meat ratio was significantly increased.In a certain range of low-phosphorus diets,with the increase of phytase content,ADG and ADFI of yellow-feathered broilers were significantly increased,and F/G was significantly decreased.The heart weight and liver weight of broilers increased with the decrease of dietary available phosphorus(P> 0.05).Myogastric weight decreased(P>0.05).When phytase was added to low phosphorus diet,the liver index of the low phosphorus group was significantly higher than that of the enzyme group(P<0.01).Dietary available phosphorus level decreased,serum calcium level decreased significantly(P<0.01),alkaline phosphatase level decreased significantly(P<0.01).There was no significant difference in serum uric acid level between the two groups(P>0.05).The serum urea nitrogen level of each group showed a decreasing trend,and there was no significant difference in total serum protein of each group(P> 0.05).In addition,phytase significantly increased serum calcium level,serum phosphorus level increased,and serum alkaline phosphatase level first increased and then decreased(P<0.01).There was no significant difference in serum uric acid level between the two groups(P> 0.05).Serum urea nitrogen levels were significantly decreased between the enzyme groups(P<0.05).There was no significant difference in total serum protein between the groups(P> 0.05).When dietary available phosphorus level was decreased,there was significant difference in tibial length but no difference in tibial circumference(P> 0.05).The fresh weight of tibia decreased(P > 0.05).There was significant difference in tibial ash content(P<0.01),but no significant difference in tibial calcium content(P> 0.05).When phytase was added to low phosphorus diet,the tibial length was significantly different(P> 0.05).There was no significant difference in tibial circumference(P> 0.05).The fresh weight of tibia was significantly different(P<0.01),the ash content of tibia was significantly different(P<0.01),and the calcium content of tibia in each group was not significantly different(P> 0.05).When dietary available phosphorus level decreased,there was no significant difference in dietary calcium utilization rate(P> 0.05),but there was significant difference in dietary phosphorus utilization rate(P<0.01).Phytase was added to low phosphorus diet,and calcium utilization rate of diet was significantly increased(P<0.01).The utilization rate of total dietary phosphorus was significantly increased(P<0.01).Under the conditions of this experiment,when the available phosphorus was 0.24%,the optimal addition amount of ultra-thermophilic phytase was 1000FTU/kg.After formula conversion,1000FTU/kg thermo-resistant phytase is equal to 0.11% available phosphorus.