Effects Of Different Diets On Growth Performance And Rumen Development Of Meat Calves

In view of the current reports about different effects on rumen function under different feeding effects of cattle were reported relatively few,60 healthy weaning calves with similar growth and development traits were selected while their mean body weight was(94.38 ± 0.25)kg in this study.The tested animals were randomly divided into A(80:20),B(70:30),C(60:40)and D(50:50)groups,with four different kinds of Total Mixed Rations(TMR).The total test period is105 days,of which the pre-test period is 15 days and the formal test period is 90 days.The effects of different diets on the growth performance and rumen morphology of weaning calves were investigated by feeding test and slaughter test.Secondly,the transcriptome sequencing technique and bioinformatics analysis was used to explore the effects of different diets molecular mechanisms of rumen development in Meat Calves.Experiment 1: Record the daily feed intake per calf,measuring the body weight and different index of body size of each calf every 30 days.After feeding for 3 months,which is the end of the test when the calves at 180 days of age,each group randomly selected 6 calves to be slaughtered,and at the same time collecting and processing of relevant samples,and the measuring of related indicators.The results showed that: 1)The diets had a significant effect on the average daily gain of meat calves(P <0.05),and ADG of group A is higher than that in other groups(P <0.05);2)The body slant growth rate of group was significantly less than group A(less for 21.73%)and group B(less for 21.76%),(P <0.05),and there was no significant difference between group C and group D,(P> 0.05);3)There was no significant difference in body height,chest circumference and leg circumference on different groups of calf calves(P> 0.05).Experiment 2:After feeding for 90 days,the animals were slaughtered and collect three pieces of2cm×2cm tissue samples from the right side of each of the bovine rhesus ascites.One was rinsed with physiological saline and placed in 4% formaldehyde solution for slicing.The other two With4 ? precooling PBS buffer rinse,wrapped with tin foil wrapped in liquid nitrogen quickly,then placed in-80 ? refrigerator frozen,stand-by.The total RNA was extracted from the rumen epithelium of group A and group D with large difference in ruminal epithelium development.The total RNA was extracted from the rumen morphology of slaughtered beef cattle.The results showed that: 1)248 differentially expressed m RNAs were screened by transcriptome sequencing,26 of which were up-regulated and 19 down-regulated,of which is significantly different were 56genes(P <0.05);2)According to the analysis and predicted on lnc RNA between two groups,there were 248 genes expressed differently,13 of which were up-regulated and 15 of which were down-regulated,and the significant difference were 37,(P <0.05);3)There were three significant differences between the m RNA and the lnc RNA,which may be involved in the rumen of the rnc RNA.