| With the advent of the era of banning the use of antibiotics in feed,it has become a trend for Chinese herbal medicine to replace antibiotics in feed additives.As a widely distributed Chinese herbal medicine plant,the Gelsemium elegans can improve the production performance of livestock and poultry.In order to provide theoretical basis for the development of ethanol extract of Gelsemium elegans into veterinary medicine feed additive for livestock and poultry production,yellow-feathered broilers which became full-grown after 77 days old were chosen as the trial animal and divided into four groups,which are the control group,low-dose group,medium-dose group and high-dose group.From 15 to 77 days,chickens of different dose groups were given feed with 0.1%,0.3% and 0.5% ethanol extract of Gelsemium elegans,seperately.Feed conversion ratio(FCR)was calculated by recording daily feed intake and daily gain.At the 77 days old,blood was taken to measure biochemical indicators.Samples were taken to determine the slaughter performance,muscle quality,visceral indexes.Viscera and intestinal slices were made and intestinal villus status were observed.The liver and feces were sequenced by transcriptome and 16 S r RNA respectively.The main results were as following:1.Growth performance: feed conversion ratio(FCR)of ethanol extract of Gelsemi um elegans dose groups decreased while daily body weight was no significant differe nce compared with the control group;2.Blood biochemical indicators: compared with the control group,the ALT conc entration of dose groups,Cr concentration of middle dose group,P concentration o f low dose group decreased,and the ratio of AST/ALT of high dose group incr eased(P<0.05).3.Slaughter performance: compared with the control group,the slaughter rate in creased,and abdominal fat rate and kidney index of dose groups decreased significan tly(P<0.05),but other indexes showed no significant difference(P>0.05).4.Muscle quality: compared with the control group,the p H value of pectoral m uscle of middle,high dose groups increased,and the p H value of leg muscle of high dose groups,the water loss rate of middle,low dose groups decreased(P<0.05).The water loss rate of pectoral muscle in low dose group increased after 12h(P<0.05).The water loss rate of pectoral muscle in dose groups,the water loss rate of l eg muscle in middle\high dose group decreased after 24h(P<0.05).The cooking loss and the tenderness of muscle showed no difference among groups(P>0.05).5.Observation of tissue sections: compared with the control group,the histomorphological observation of major organs in the high-dose group showed no significant changes,while villi height and the ratio of villi height to crypt depth of ileum in the low-dose group increased significantly(P<0.05).6.Transcriptome: the genetic variations in different periods of several substances in the body(carboxylic acid,keto acid,nucleic acid,etc.)on the metabolism of the enrichment were found significantly.The results were verified by fluorescence quantitative PCR,among which BLB2,PCK1,AOX1,HMGCL and IL21 R were basically consistent with the trend of the transcriptome.7.16 S rRNA sequencing: the results showed that the use of enthanol extract of Gelsemium reduced the proportion of Firmicutes/Bacteroides,and significantly increase d the relative abundance of Gastranaerophilales,Enterococcaceae,Clostridiales,Achn ospiraceae,Ruminococcus,Enterobacteriales.The systematic evaluation of the growth-promoting effect of yellow-feathered broilers and its related effects was carried.It provided experimental basis for the development of ethanol extract of Gelsemium elegans as a new veterinary drug,and the reference for the substitution of Chinese herbal medicine for growth-promoting antibiotics. |
PDF Full Text Request