Effect Of Flax Seed Cake Instead Of Soybean Meal On Growth Performance,Blood Biochemical Indicators,Rumen Fermentation Of Sheep

The objective of this experiment was to investigate the effects of substitution of soybean meal by flax seed cake on the growth performance,meat quality,fatty acid content and blood biochemical indicators of lambs.A total of 24 F1 DorperxSmall Tail Han sheep(5 month old,26±1 kg)were randomly selected and equally assigned into 4 groups according to the proportion of flax cake substituted soybean meal(0,1/3,2/3 and 3/3):control group(CK group),treatment ?,? and ?.Experiment period was 60 days.The result showed that:there was no significant difference in daily gain between treatment group and CK group(P>0.05).Compared with the CK group,the feed to gain ratio of group ? was significantly declined(P<0.05).There was no significant difference for carcass weight and net meat weight between treatment and CK group(P>0.05).The slaughter rate,net meat percentage and longissimus dorsi(LD)muscle cross area of group ? were significantly higher than those in control group(P<0.05).The organ idex of liver and lung of group ? were significantly lower than those in other three grops(P<0.05).There were no significant difference in organ idex of heart,kidney,rumen,reticilum,omasum and abomasum between treatment group and CK group(P>0.05).The substitution of soybean meal effectively declined intramuscular fat content and reduce meat tenderness(P<0.05),whereas the values of pH,water holding capacity and cooked meat percentage were not altered(P>0.05).Interestingly,dietary substitution can significantly increase the content of C20:5N3 in LD muscle,and there was no significant effect on saturated fatty acids,monounsaturated fatty acids and polyunsaturated fatty acids(P>0.05).Contents of TC,LDL and activity of SOD remained unchanged between treatment and CK groups(P>0.05).The contents of TG in group ? and ? were significantly lower than those in CK group(P<0.05).The content of HDL in group ? was greater than that in other three groups(P<0.05).The contents of UREA in group ? and ?were significantly lower than those in group CK and group ?(P<0.05).The MDA content of group ?was significantly lower than other three groups(P<0.05).The activity of CAT in group ? was significantly greater than other three groups(P<0.05).There was no significant difference in the activity of carboxymethyl cellulose enzyme in rumen fluid between treatment group and CK group(P>0.05).The activities of pesin and xylacase in rumen fluid of group ? and ? were significantly higher than CK group.The activity of ?-glucosidase in rumen fluid was significantly lower than that in the treatment(P<0.05).And the activity of pectinase in group ? was significantly higher than that in the other three groups(P<0.05).There was no significant difference in pH value,total VFA content and ammonia N concentration between the treatment group and control group(P>0.05).Compapre with the group ? and?,the ratio of acetate to butyrate and the content of mycoprotein in the rumen fluid of treatment ? and group CK(P<0.05).There was no significant difference in the activity of SOD,the T-AOC and the content between treatment and control group(P>0.05).The activity of CAT in the liner of the group ? and ? was significantly higher than that in the group ? and CK group(P<0.05).The activity of GSH-Px in the liver of group ? was significantly higher than that of other three groups(P<0.05).Dietary substitution of soybean meal by flax seed cake can reduce feed to gain ratio and improve the growth performance,reduce blood lipids,improve the activity of cellulase and pepsin in rumen fluid,improve the rumen environment and improve sheep antioxidant capacity.Therefore,oil cake of flax seed can be used as a protein source of sheep feed.The optimal substitution rate should be 2/3.