Study On The Effects Of Xylanase Supplementation In Low Me Diet In Broilers

The broiler chickens is the research object in this study, add the xylanase in the different levels low ME Corn-soybean meal diet, study the effects of xylanase on the growth performance, apparent digestibility of nutrients, carcass quality and immune organ index in broilers. The results are as follows:Test 1:Two hundred eighty-eight one-day-old Avain broilers were randomly divided into four groups of six repeats, each repeat had twelve chickens. One acted as control group and fed Corn-soybean basal diet, another three treated groups were separately fed-0.252MJ/kg,-0.42MJ/kg and-0.63MJ/kg low ME basal diet and all supplemented 100g/t xylanase. The test has 7 weeks and study the effect of xylanase in low ME diet on growth performance and immune organ index in broilers. The test results showed that there were on difference for hatch weight between control and three treatment groups (P>0.05); There were significant difference for finish weight and ADG between treatment 2 and control group (P<0.05), the treatment 1 and 3 had not significant difference with control group (P>0.05), but its had the rising trend. The finish weight were respectively increased by 6.18% and 0.50% with control, the average daily gain were respectively increased by 6.32% and 0.51% with control; There were extremely significantly difference for ADFI between control and three treatments (P<0.01), the ADFI of the treatment 1 and 2 were increased by 1.74% and 2.54%, but the ADFI of treatment 3 were decreased with control. There were no difference for F/W between control and the three treatments (P>0.05). To immune organ index:Thymus index of treatment 1 and 2 was significantly increased than control group (P<0.05), its were increased by 7.58% and 7.94% respectively; There were no difference for spleen index and bursa index between control and the three treatments (P>0.05), the spleen index and bursa index of treatment 3 were decreased a little with control,but its of treatment 1 and 2 had rising trend, the spleen index of treatment 1 and 2 were respectively increased by 3.42% and 9.40%, the bursa index of treatment 1 and 2 were respectively increased by 7.27% and 16.36%. In a word, add the xylanase in the different levels low ME Corn-soybean meal diet, the growth performance of the broilers in three treatments had the same even the better effect with the control group. The three treatments could increased the immune organ index, which explain increased the immunity of the broilers.Test 2:Twenty 6-week-old Avain broilers which had the similar weight were randomly divided into four groups, each group of six chickens and feed 1 week to study the effects of adding the xylanase in the different levels low ME Corn-soybean meal diet on the apparent digestibility of nutrients. The results were as follow:The apparent digestibility of each nutrient all had the changes in Varying degrees. The CP apparent digestibility of treatment 2 was significantly increased than control and treatment 1 (P<0.05), there were no significant difference between control and treatment 1 and 3 (P>0.05), but its all had the rising trend. The EE apparent digestibility of treatment 2 was significantly increased than the other groups (P<0.05), there were no significant difference between control and treatment 1 and 3 (P>0.05); The Ash apparent digestibility of treatment 2 and 3 was significantly increased than the control groups (P<0.05), there were no significant difference between control and treatment 1 (P>0.05), but the ash apparent digestibility of treatment 1 was increased by 7.15%; The Ca apparent digestibility of treatment 1 and 2 was extremely significantly increased than the control group (P<0.01), the Ca apparent digestibility of treatment 3 was significantly increased than the control group (P<0.05); The P apparent digestibility of the three treatments was extremely significantly increased than the control group (P<0.01), but there were no difference in the three treatments (P>0.05). The test results showed that adding the xylanase in the different levels low ME Corn-soybean meal diet could eliminates the disturbance effectively of the anti-trophic factors, improve the nutritional value of diets and promot nutrient digestion and absorption.Test 3:Twenty-four 7-week-old broilers were selected randomly and slaughtered to study the effects adding the xylanase in the different levels low ME Corn-soybean meal diet on carcass quality. The results as follow:The dressing percentage of the three treatments was extremely significantly increased than the control group (P<0.01), at the same time, the dressing percentage of treatment 2 was significantly increased than the treatment 3 (P<0.05); There were no difference for PHE, PBM, PTM and relative liver weight between control and the three treatments (P>0.05). The PE of the treatment 3 was extremely significantly increased than the control group (P<0.01), there were no difference for PE between control and the treatment 1 and 2 (P>0.05), but its had the rising trend. The liver weight of the treatment 2 was significantly increased than the control group (P<0.05), but there were no significant difference for liver weight between control and the treatment 1 and 3 (P>0.05).At the same time, there were no significant difference for PAF between control and the three treatments (P>0.05), but the PAF of three treatments were decreased. The results showed that adding the xylanase in the different levels low ME Corn-soybean meal diet could improve the carcass quality of broilers.