Mechanism Of Harvest,Storage And Utilization Of Typical Steepe

The major cause of the differences between the intake of hay and pellets may be the characteristics of dominant grass and pelleting process since the chemical composition was the same.Native grassland is the foundation for husbandry.Typical Steepe not only the important part for Mongolian Plateau,but also the main foundation for native grass hay.In present,the native grass hay has lower feeding value and commercial value.Because of the harvest and processing technology exist some disanvantage,the lower quality and utilization of native grass hay.On the other hand,Stipa is a dominant grass genus in Mongolian native grasslands,and the young leaves and stems in early spring and regeneration material in autumn are highly palatable.However,after harvesting,this grass has awn needles on the caryopses,which become hard and sharp at maturity,reducing the feed intake.These effects make the commercial value of native grass hay decreasing,continuously.Some researches were carried to solve the problems on harvest,processing,storage and utilization of native grass.The harvest and processing technology were confirmed based on the yield and chemical composition of native grass.Based on the former research,the effect of baling density and stack ways on chemical composition and mycotoxin of native grass hay were also studied.We also confirmed the storage condition.The native grass hay was used in the feeding expperiment.The growth performance,carcass characteristic and meat quality as the index in the feeding experiment.Based on this research,the correlations among native grass,hay and the meat product were confirmed.These results would provide the theory and technology for harvest,storage and utilization in Typical Steepe.In the present study,we selected Maodeng Farm as experimental site.The experimental material was Typical Steepe Native grassland and Mongolian lambs.The experiment was desigened by randomized block design and randomized split-plot experiment(2x3 factors).The research and production was combined.To evaluate the theory and techonology of harvest,processing,storage and utilization that the Native grass experiment and feeding wxperiment were carried in Typical Steepe.The results indicate that:(1)Combination with the hay yield,regrowth performance and nutrition quality,the native grassland should harvet in the period from heading stage to florescence.(2)The Native grasses after drying 72h have achieved safety moisture content to baling.Their interaction of cutting and drying time on DM and CP have a significant differences on hay(P<0.05).The interaction between cutting time and drying time had a significant effect on CP content of natural forage hay,which indicated that hay quality was affected by cutting time and drying time.The quality of native grass hay was determined by cutting time and drying time.The getting damp and drying time have a negative effect on native grass quality.In order to get the hay with better quality,it is necessary to harvet earlier of the day.Enhancing the speed of dry and decreasing the drying time.(3)The effect of baling density and stacking ways on chemical composition and mycotoxin of native hay in Typical Steepe indicate that baling density have no significant(P<0.05)effect on Ash,DM(dry matter,DM),NDF(neutral detergent fiber,NDF),AFB;(aflatoxin B1,AFB1),T-2(T-2 toxin)and OTA(ochratoxin A,OTA).It has a significant(P>0.05)effect on ADF(acid detergent fiber,ADF),CP(crude protein,CP),DON(deoxynivalenol,DON)and ZEN(zearalenone,ZEN).The stacking ways have no significant(P>0.05)effect on Ash,DM,ADF,NDF,CP,DON,AFB1,T-2 and OTA.And it has a significant(P<0.05)effect on ZEN.The baling density,stacking ways,and their interactions could significantly improve the contents of chemical composition and mycotoxin.Based on the chemical composition and mycotoxin content,the baling density of 160 kg/m3 and cross-stacking way were better in Typical S teepe.(4)The effect of Native grass produt has a positive effect on small ruminant.Fresh grass intake was higher than pellet intake,and hay intake was lower than pellet intake(both P<0.05).The lambs in the hay group exhibited daily weight loss,while the daily weight gains of the lambs in the grass and pellet groups were increased(P<0.05).The body weight before slaughter,carcass weight,net meat mass,loin muscle area,and FT(a measure of fat tissue thickness)were greater(P<0.05)in sheep given the grass and pellet treatments than in those given the hay treatment.Compared with the hay treatment,the marbling score,water loss,and the contents of protein were significantly increased in the grass and pellet treatments,whereas the fat,Ca,a*,and b*values were significantly decreased.The results indicate that feeding native grass or pellets is more beneficial than feeding Inner Mongolian hay for the growth performance and meat quality of Mongolian lambs.(5)The growth performance and meat quality of Mongolian lamb fed hay with or without concentrate,and the grass impact were also studied.Fresh grass intake was greater(P<0.05)and hay intake was lower(P<0.05)than HC intake.Hay group had a daily gain of-58.67 g/d,whereas they were 42.33 g/d for hay+concentrate group and 80.00 g/d for grass group.The carcass weight,net meat mass,loin muscle area and FT(a measure of fat tissue thickness)were greater(P<0.05)in the grass and HC groups than those in hay group,while the dressing percentage,bone mass,net meat percentage,moisture and ash contents of sheep did not differ among these groups.Compared with the hay group,the crude protein,calcium,marbling score and water loss rate were significantly greater for grass and HC groups,whereas the fat,phosphorus,b*and cholesterol were significantly lower.These results confirmed that feeding of native grass hay with concentrate could improve the growth performance and meat quality of Mongolian lambs,which can achieve similar results to feed grass.