Bacterial Enzyme Preparation Fermented Straw And Its Effect On The Rumen Degradation Rate Of Sheep

Straw resources are abundant and huge crop by-products cannot be used reasonably in China,leading to a series of environmental pollution problems.The utilization efficiency of corn stalk is limited because of its low protein and high fiber.Using crop by-products reasonably and effectively,which can not only ease the contradiction between humans and animals for food,but also reduce the cost of straw treatment and reduce the environmental pollution of incineration.In this experiment,corn stalk was fermented by Phanerochaete chrysosporium and composite enzyme?cellulase,xylanase?as fermentation agents,and the supplemental ratio of fungus and enzyme composite fermentation were selected.The effects of this fermented feed on the rumen fermentation in vitro and rumen degradation rate of sheep were investigated,which provided theoretical basis for the development and utilization of unconventional feed.?1?The optimal fermentation conditions of the fermentation of corn stalkThe experiment used the uniform deign.The purpose of the experiment was NDF degradation rate and ADF degradation were used as evaluation indexes.Four factors,the inoculation amount of Phanerochaete chrysosporium,the supplemental amount of cellulase and xylanase,and the fermentation days were screened,and the fermentation effect was evaluated and compared.The results showed that:the content of DM and CP of fermented corn stalk was significantly higher than that of unfermented straw group?P<0.05?;the contents of NDF?ADF and ADL were significantly lower than that of unfermented straw group?P<0.05?;the optimal fermentation conditions were screened as follows:cellulase and xylanase were added in amounts of 0.2 g/kg and 0.1 g/kg,respectively.The inoculation amount of Phanerochaete chrysosporium was 20%,and the fermentation days were 19 d.Under this condition,the degradation rates of NDF and ADF in the corn stalk reached 23.47%and 20.13%,respectively.The verification experiment results of fermentation showed that the fermentation of corn stalk with the fungus enzyme compound preparation significantly improved its nutritional value and fermentation quality,and scored well.?2?Effects of fungus and enzyme fermentation corn stalk on rumen fermentation parameters in vitroThe single factor completely random group design was used in the experiment.The experiment was divided into 3 groups,each group was 3 repeated.The unfermented straw group was the control group,the fungus enzyme complex fermentation group and the commercial enzyme preparation group were the experiment group respectively.The rumen fermentation indices in vitro were measured at 3,6,12,24,48 h after culture.The results showed that:the gas production of the fungal enzyme complex fermentation group and the commercial enzyme preparation group was significantly higher than that of the control group?P<0.05?.From high to low in order:the fungal enzyme complex fermentation group>commercial enzyme preparation group>control group;The pH range of rumen fluid in three groups was 6.36⁶.74,all of them in the normal range,and the difference was not significant?P>0.05?;the NH₃-N concentration of the fungal enzyme complex fermentation group and the commercial enzyme preparation group were significantly higher than that of the control group?P<0.05?,from high to low in order:fungal enzyme compound fermentation group>commercial enzyme preparation group>control group;BCP concentration of fungal enzyme compound fermentation group and commercial enzyme preparation group were significantly higher than the control group at 24⁴8 h?P<0.05?,from high to low in order:fungal enzyme compound fermentation group>commercial enzyme preparation group>control group.?3?The effect of fermentation of corn stalk by fungus and enzyme on the rumen degradation rate in sheepThe Latin square design was adopted in the experiment.Six healthy and similar sheep with permanent rumen fistulas were selected and divided into three groups,fed with the same basic diet,and incubated in the rumen with nylon bag method,the degradation rates of DM,CP,NDF and ADF were determined at 6,12,24,48,and 72 h.The results showed that:the DM degradation rate of the fungus enzyme complex fermentation group and the commercial enzyme preparation group were significantly higher than that of the control group?P<0.05?at each time point.The degradation rate of CP in the fungal enzyme fermentation group and the commercial enzyme preparation group was significantly higher than that in the control group?P<0.05?at each time point.During the 24⁴8 h of culture,the fungal enzyme fermentation group were significantly higher than the commercial enzyme preparation group?P<0.05?.The degradation rates of NDF and ADF were slower at 0⁶ h,and there was no significant difference between the two trial groups and the control group?P>0.05?.The degradation rates of NDF and ADF were significantly higher in the two trial groups at 12⁷2 h than the control group?P<0.05?,and the ADF degradation rate of the fungal enzyme compound fermentation group incubated for 72 h was significantly higher than that of the commercial enzyme preparation group?P<0.05?,and its effective degradation rate was significantly higher in the two trial groups than the control group?P<0.05?,and the fungal enzyme compound fermentation group was significantly higher than the commercial enzyme preparation group?P<0.05?.In summary,the fermentation of corn stalk by the fungal enzyme compound preparation improved its nutritional value,contributed to rumen fermentation in vitro,and increased the rumen degradation rate of sheep.