Effects of Low Protein Diet Supplemented with Rumen-protected Amino Acids on Growth Performance,Nutrient Apparent Digestibility and Meat Quality of Hulun Buir Sheep
This experiment was conducted to investigate the effects of dietary rumen-protected ly-sine(RPLys)and rumen-protected methionine(RPMet)supplemented in low-protein diet on growth performance,nutrient apparent digestibility,serum biochemistry and meat quality of Hu-lun Buir sheep.Sixteen 2.5-month-old weaned healthy lambs were randomly divided into two groups evenly:control group(fed low protein diet with crude protein content of 7.84％)and treatment group(supplemented with 10 g·d-1 RPMet and 15 g·d-1 RPLys on the basis of low protein diet).The pretrial period lasted for 7 d and the experimental period lasted for 56 d.The results showed that:1)The average daily feed intake of treatment group was significantly lower(P＜0.05),but its average daily height increase was significantly higher(P＜0.05),and feed to gain ratio of treatment group was lower than that of control group.2)There was no significant difference in slaughter performance or nutrient apparent digestibility between two groups(P＞0.05).3)The contents of total protein(TP),albumin(ALB),creatinine(CREA),lactate de-hydrogenase(LDH),alanine aminotransferase(ALT)and low density lipoprotein(LDL)in the serum of treatment group were significantly lower than those of the control group(P＜0.05),and the content of free fatty acid(NEFA)was significantly higher(P＜0.05)than that of the control group.4)There was no significant difference in meat color,conventional nutrients,the composition and content of fatty acid between the two groups(P＞0.05).The content of threo-nine(Thr)in muscle of treatment group was significantly higher(P＜0.05),and the contents of isoleucine(Ile),leucine(Leu),tyrosine(Tyr)were significantly lower than those of the control group(P＜0.05).The proportion of flavor amino acids and essential amino acids in total amino acids(DAA/TAA,EAA/TAA)in muscle of treatment group were significantly higher(P＜0.05),and the ratio of essential amino acids to non-essential amino acids(EAA/NAA)was sig-nificantly higher than those of the control group(P＜0.05).In conclusion,under the condition of the current experiment,adding 10 g·d-1 RPMet and 15 g·d-1 RPLys into the low protein diet has a positive effect on the growth and development of Hulun Buir sheep,and without affecting its nutrient digestibility and slaughter performance.It can also increase the proportion of delicious amino acids and essential amino acids in muscle and improve muscle quality.
万方数据
维普
