Effects Of Dietary Lactobacillus Reuteri Supplementation On Meat Quality Of Sunit Sheep

In this study,16 Sunit sheep were randomly divided into Lactobacillus reuteri group and control group,with 8 sheep in each group.The effects of dietary Lactobacillus reuteri supplementation on meat quality of Sunit sheep were studied.The growth performance,slaughter performance and meat quality of two groups of Sunit sheep were determined.The volatile flavor compounds of Sunit sheep were determined by solid phase microextraction-gas chromatography-mass spectrometry.The composition and content of fatty acids in Sunit sheep were determined by gas chromatography.The longissimus dorsi muscles of two groups of Sunit sheep were detected by non-targeted metabolomics detection technology,the differential metabolites were screened,and the enrichment pathways of differential metabolites were analyzed.The results are as follows:The loin eye area,water content and intramuscular fat content of Sunit sheep in Lactobacillus reuteri group were significantly increased（P<0.05）,and the pH_24hvalue and shear force value were significantly decreased（P<0.05）.The types of volatile flavor substances in Sunit sheep in Lactobacillus reuteri group were more than those in control group.The relative contents of benzaldehyde,dodecanal,trans-2-decenal and1-octen-3-ol were significantly higher than those in the control group（P<0.05）,and the relative contents of heptanal,nonanal,undecanal,heptanol,ethylbenzene and phenol were significantly lower than those in the control group（P<0.05）.This indicates that the types of volatile flavor substances in Sunite sheep can be increased,and the relative content of volatile flavor substances can be improved by adding Lactobacillus reuteri to the diet.In the effect of Lactobacillus reuteri on the fatty acid composition of Sunit sheep,it was found that dietary Lactobacillus reuteri significantly reduced the relative content of stearic acid and total saturated fatty acid in the longissimus dorsi muscle of Sunit sheep（P<0.05）.The relative content of cardamom oleic acid in monounsaturated fatty acids was significantly increased（P<0.05）.The relative contents ofγ-linolenic acid,arachidonic acid,eicosapentaenoic acid,tetracosenoic acid and total polyunsaturated fatty acids were significantly increased（P<0.05）.It is indicated that the composition of fatty acids in the longissimus dorsi muscle of Sunit sheep can be improved by adding Lactobacillus reuteri to the diet.Through the detection of metabolites in the longissimus dorsi muscle of the Lactobacillus reuteri group and the control group Sunit sheep,a total of 104 metabolites with significant differences were screened,including amino acids,peptides and their metabolites,fatty acids and conjugates,glycerophosphocholine,carbohydrates and conjugates,nucleotides and their metabolites,etc.Pathway enrichment analysis of differential metabolites using KEGG database showed that 33 metabolic pathways were enriched.The main metabolic pathways included Fox O signaling pathway,AMPK signaling pathway,glutathione metabolism,glycerophospholipid metabolism,purine metabolism and tryptophan metabolism.