Effects Of Different Ratios Of Peanut Seedling And Whole Plant Corn Silage On Growth Performance,Meat Quality And Rumen Micro Flora Of Simmental Crossbred Cattle

This experiment aims to study the different ratios of peanut seedlings and whole-plant corn silage in Simmental crossbred cattle diets,and to explore the appropriate ratio of peanut seedlings and whole-plant corn silage in Simmental crossbred cattle diets to Simmental crossbreds The influence of cattle performance,meat quality and rumen microflora.Choose 1 00 beef cattle that are healthy,similar in weight（about 450kg）,and similar in age（about 18 months of age）,and the breed is Simmental crossbred cattle.According to the composition of the roughage,they were randomly divided into 4 groups（5 replicates for each treatment,and 5 cows for each replicate）,which were 45%wheat straw group（wheat straw group,WG）and 25%peanut vine group（Low peanut vine group,LPG）,45%peanut vine group（Medium peanut vine group,MPG）and 65%peanut vine group（High peanut vine group,HPG）.The roughage of the WG contained 45%wheat straw,the roughage of the LPG contained 25%peanut seedlings,the roughage of the MPG contained 45%peanut seedlings,and the roughage of HPG contained 65%peanut seedlings.The pre-test period is 7 days and the official period is 90 days.Exp.1:The main research is to study the effect of different ratios of peanut seedlings and whole corn silage on the performance and economic benefits of Simmental crossbred cattle.The results showed that:（1）The final weight,average daily feed intake and average daily gain of the MPG group were significantly higher than the other three groups（P<0.05）.The difference of F/G between the four treatment groups was not significant,and the ratio of material weight in LPG group was the lowest（P>0.05）.（2）In serum,MDA in HPG and SOD in LPG were significantly higher than that in WG（P<0.05）;in liver,MDA in HPG was significantly higher than that in WG（P<0.05）;In the spleen,the SOD activity of the LPG,MPG and HPG was significantly higher than that of the WG（P<0.05）.（3）The weight gain cost of MPG was significantly higher than that of WG,LPG and HPG（P<0.05）,while the gross profit of MPG group was the highest,and it was significantly higher than that of WG and HPG（P<0.05）.Exp.2:Further study the effect of different ratios of peanut seedlings and wholeplant corn silage on the quality of Simmental crossbred beef.The results showed that:（1）The carcass weight,net meat weight and eye muscle area of the MPG group were significantly higher than WG,LPG and HPG（P<0.05）.（2）There was no significant difference in organ index among the four treatment groups（P>0.05）.（3）The four treatment groups have no significant differences in marbling,cooking loss,hydraulic power,shear force and pH48（P>0.05）,but MPG has a tendency to improve the score in terms of marbling.（4）The dry matter and crude protein of the MPG group were significantly higher than the other three groups,while the LPG group was significantly higher than the other three groups in terms of crude fat（P<0.05）.In terms of crude ash content,the four treatment groups had no significant difference（P>0.05）.（5）The content of linoleic acid in LPG,MPG and HPG was significantly higher than that in WG（P<0.05）.（6）The expression of FAS,LPL and MDH2 genes in the LPG group was significantly higher than the other three groups（P<0.05）.Exp.3:The 16S rDNA technology was used to study the effects of different ratios of peanut seedlings and whole-plant corn silage on the rumen microbial diversity and rumen microflora metabolism of Simmental crossbred cattle.The results showed that:（1）The concentration of NH3-H in WG,LPG,MPG and HPG decreased sequentially（P<0.05）.The content of acetic acid and propionic acid in the LPG group was significantly higher than that of WG,MPG and HPG（P<0.05）,and the A/P of the HPG group was significantly higher than that of WG,LPG and HPG（P<0.05）.（2）The Chao index of HPG is higher than that of WG（P<0.05）.（3）At the phylum level,the relative abundance of Firmicutes in MPG and HPG was higher than that in WG（P<0.05）;the relative abundance of Bacteroidetes in MPG and HPG was lower than that in WG（P<0.05）.（4）At the genus level,compared with the WG group,the MPG group and the HPG group can significantly reduce the relative abundance of Prevotella₁（P<0.05）,and the relative abundance of Prevotella₁ in the four treatment groups was WG>LPG>MPG>HPG;Compared with the WG group,the HPG group can significantly increase the relative abundance of Ruminococcus₂（P<0.05）,and the relative abundance of Ruminococcus₂ in the LPG group,MPG group and HPG group is higher than that of the WG group.（5）Correlation analysis of rumen microbes and metabolites and lipid metabolism-related genes at the genus level showed that Prevotella₁ was positively correlated with the content of acetic acid（P<0.05）,and Succiniciasticum was correlated with propionic acid,butyric acid and total volatile fatty acid.There was a positive correlation;Rikenelaceae_RC9_gut_group was negatively correlated with the acetic acid content（P<0.05）.（6）The function prediction analysis of rumen microflora showed that compared with the WG,LPG,MPG and HPG had an up-regulation of the functions of genes related to membrane transport,lipid metabolism,and transcription.Genes related to biosynthesis and metabolism are down-regulated.To sum up:the different ratios of peanut seedlings and whole-plant corn silage in Simmental crossbred cattle diets can improve beef cattle production performance and economic benefits,and can enhance the antioxidant capacity of beef cattle serum and tissues,but with peanut seedlings The increase of the proportion of the body reduces the oxidative stress ability,which can improve the quality of beef meat,increase the crude fat content and the deposition of linoleic acid in the beef,improve rumen fermentation and induce changes in the rumen microflora,while regulating the changes in rumen metabolic pathways.