Study On The Processing Technology And Application Of TMR For Sheep

Object:This paper studies the processing technology and application effect of total mixed diet(TMR)pellet feed for pregnant ewes under extreme climate conditions,aiming to improve the ability of grazing sheep to resist disasters.Methods:In this paper,the molding quality and application effect of TMR pellet feed with different concentrate to roughage ratio were studied.Part one.The effect of concentrate to roughage ratio on the molding quality of TMR pellets was studied.Three different levels of concentrate to roughage ratio(50:50?40:60?30:70)were designed.Corn straw and alfalfa hay were used as roughage.The ratios of the two were 1:2?1:1?2:1.According to the production process of TMR pellet feed,the TMR pellet feed was produced.The effects of factor A on sensory properties,flour content,pulverization rate,hardness,bulk density,density,length and diameter of TMR pellets were compared to evaluate the quality of TMR pellets.TMR pellet feed of A1B1 group was selected as control group,VE(20 IU/kg,40 IU/kg,60 IU/kg),VC(250 mg/kg,500 mg/kg,750mg/kg)and ethoxyquine(100 mg/kg,200 mg/kg,300 mg/kg)were added to the feed.According to the production process of TMR pellet.Storage at room temperature,samples were collected at 0,15,30,60,90,120 days after production.The activity of·O₂^-,H₂O₂ Content,·OH,activity and total antioxidant capacity were determined.The antioxidant capacity of different antioxidants on TMR pellet feed at different time points was studied to determine the appropriate antioxidant type and dosage.A1B1 group of TMR pellet was used as the basic feed,different levels of citric acid,alcium lactate and fumarate were added to the feed.According to the production process of compressed TMR pellet feed.The samples were collected at 0,15,30,60,90,120 and 150 days after production.The changes of environmental temperature and humidity,moisture in feed,sensory changes,total number of molds and mold distribution were determined to determine the appropriate type and dosage of mold inhibitor.Part two.The feeding experiment was carried out with the Part one of TMR pellet feed.The feeding behavior and rumination behavior of pregnant ewes were observed,digestion and metabolism tests and in vitro fermentation tests were carried out.The biochemical indexes in blood of pregnant ewes were measured to evaluate the application effect of condensed TMR pellet feed.Results:(1)With the decrease of concentrate ratio and the increase of roughage ratio,the sensory quality of TMR pellet decreased,the powder content and pulverization rate increased significantly(P<0.05),hardness decreased significantly(P<0.05),bulk density and density decreased significantl(P<0.05),particle length increased significantly(P<0.05),but the particle diameter had no significant effect(P>0.05).There was no significant difference in feed quality between corn straw and alfalfa hay ratio(P>0.05);the interaction between different concentrate to forage ratio and the composition of roughage had significant effect on grain bulk density and density(P<0.05).(2)During the storage period of 0?120 days,the oxidant addition groups could effectively remove H₂O₂,·OH,·O₂^-produced in the process of feed oxidation,and improve the total antioxidant capacity of feed.The ability of scavenging free vitamin E and vitamin C increased with the increase of concentration and time.In the initial stage of storage,there was no significant difference in antioxidant capacity(P>0.05);the antioxidant effect of different doses of antioxidants in the early and middle stage of storage was different,and the difference was not significant(P<0.05).(3)During storage,the temperature range of the storage room is 16.5??28?,the average indoor temperature is 22.02?,the relative humidity is 33%?75%,and the average relative humidity is 46.04%.On the 15th day,the water content in the feed decreased and began to rise at the30th day,with no significant difference among the groups(P>0.05).On the 60?150th day,the water content of the control group was significantly higher than that of the experimental groups(P<0.05).Within the 0?90th days,the appearance of feed in each group remained good,and there was no mildew.At the 120th days,the feed of control group showed mildewed.At the 150th days,the control group was mildly moldy.At 15?120th days,the number of molds in the feed was more than that in each fungicide group,and the difference was not significant(P>0.05).At the 120?150th days,the number of molds in the control group was significantly higher than that in the three fungicide groups(P<0.01),but there was no significant difference among the fungicide groups(P>0.05).By PCR-DGGE analysis,it was found that the main molds related to feed hygiene were Fusarium,Aspergillus and Penicillium.(4)The feed intake of ewes was significantly higher when the ratio of concentrate to roughage was 50:50,which was significantly higher than that of the 40:60 and30:70 groups,and the dry matter intake was increased by 14.76%and 19.13%respectively(P<0.05).TMR could shorten the feeding time and provide feeding speed.High proportion of concentrate could increase the frequency of drinking water and defecation.The feed with different treatment had no significant effect on the movement and rest time of pregnant ewes(P>0.05).There was no significant difference in rumination behavior between ewes fed compressed TMR diet and bulk TMR diet(P>0.05).The digestibility of CP,CF,Ca and P in TMR treated with compression was higher than that of control group.Factor a had significant effect on CP and CF,but had no significant effect on Ca and P digestibility(P>0.05).(5)In vitro fermentation for the 2-8th hours,the gas production,NH3-N concentration,MCP concentration and VFA concentration in the culture medium increased rapidly,the p H value and acetic acid/propionic acid value decreased,and the change speed slowed down from 8 to12 hours,and reached the peak value at 24 hours;with the increase of concentrate ratio in feed,p H value and acetic acid/propionic acid value in rumen fluid decreased,and gas production,NH3-N concentration,MCP concentration and VFA in culture medium increased.(6)When pregnant ewes were fed with compressed TMR,within the experimental range,the higher the proportion of alfalfa hay in feed,the higher the contents of TP,ALP,BUN and CRE in serum of pregnant ewes.Different concentrate to forage ratio and different corn straw:alfalfa hay ratio had no significant effect on serum Bl,TG,Ca,P in pregnant ewes(P>0.05),while maintaining the balance of serum concentrations of Blu,TG,Ca and P under the premise of ensuring the nutritional needs of ewes.Conclusion:When the ratio of concentrate to roughage was in the range of 50:50?30:70,the higher the concentrate ratio was,the more favorable it was for the formation of TMR pellet;under the same concentrate to forage ratio,increasing the proportion of corn straw decreased the proportion of alfalfa hay,and the grain bulk density and length decreased accordingly.Adding different levels of VC,VE and ethoxyquine in feed can improve the antioxidant capacity of feed.Adding different levels of citric acid,calcium lactate and fumaric acid can effectively inhibit the growth and reproduction of mold and prolong the shelf life of feed.Feeding TMR pellet feed can ensure the health of pregnant ewes,normal physiological and biochemical indexes,improve feed palatability,and increase dry matter intake and digestibility.