Effects Of High-concentrate Diet Supplemented With Grape Seed Proanthocyanidins On Nutrient Digestion And Metabolism,Growth And Slaughter Performance In Fattening Lambs

This experiment was conducted to investigate the Effects of high-concentrate diet supplemented with grape seed proanthocyanidins(GSPs)on growth performance,slaughter performance,nutrient digestion and metabolism in fattening lambs.A total of forty-eight 1/2 Dorper × 1/2 thin-tailed Han ram lambs were fed a70:30 forage:concentrate diet and were randomly divided into four groups,All the lambs fed a basic diet and supplemented with 0(CON),10(10GSPs),20(20GSPs)and 40 mg/kg BW(40GSPs)GSPs.The feeding experiment l7 ed for 60 days,including a 15-day adaptation period.After the feeding experiment,six sheep were selected randomly for the slaughter and the digestion metabolism experiment.The results as follows:(1)average daily gain(ADG)and average daily feed intake(ADFI)of 10 GSPs and 20 GSPs were significantly higher than the control and 40 GSPs group(P<0.05).The final weight(FW)and shrunk body weight(SBW)of 10 GSPs and 20 GSPs were higher than the control group(P<0.05),and have no difference with 40 GSPs(P>0.05);(2)The carcass weight and net meat weight of 10 GSPs,20GSPs,and 40 GSPs groups were significantly higher than the control group(P<0.05);(3)The a*1h of 20 GSPs was higher than the control and 10 GSPs groups,and the warner-Bratzler shear force of 20 GSPs and 40 GSPs were significantly lower than the control and 10 GSPs groups(P<0.05);(4)Compared with the control group,20 GSPs and 40 GSPs had higher SOD and GSH-PX activities content in serum(P<0.05);(5)The rumen p H of the 20 GSPs and 40 GSPs groups after feeding for 0,3,and 8 h was significantly higher than the control group and 10 GSPs group(P≤0.05).The concentration of acetic acid,total volatile fatty acids and NH3-N tends to decrease(P<0.1)(6)The apparent digestibility of CP of 20 GSPs group was significantly higher than the control group(P≤0.05),the NDF of 40 GSPs group was significantly lower than the other three groups(P≤0.05),and the apparent digestibility of DM and OM in the 20 GSPs group was significantly higher than that in the control and 40 GSPs groups(P≤0.05);(7)GSPs had no significant effect on fecal and urinary nitrogen(P>0.05).The nitrogen intake and nitrogen deposition rates of the20 GSPs group were significantly higher than those of the control and 40 GSPs groups(P≤0.05).The apparent digestibility of nitrogen in the 20 GSPs group was significantly higher than that in the control group(P≤0.05).The deposition nitrogen of the 20 GSPs group was significantly higher than that of the10 GSPs group,and the deposition nitrogen of the 10 GSPs group was significantly higher than that of the40 GSPs group(P≤0.05).;(8)Allantoin,total purine derivatives and MCP in the 40 GSPs group was significantly lower than the other three groups(P≤0.05);(9)The total energy intake,apparent digestibility and apparent metabolic energy of the 10 GSPs and 20 GSPs groups were significantly higher than that of the control group and 40 GSPs group(P≤0.05).the methane energy of the 20 GSPs and 40 GSPs groups was significantly lower than that of the control group(P≤0.05).the apparent digestibility of the 10 GSPs group was significantly higher than that of the 20 GSPs and 40 GSPs groups(P≤0.05).The apparent digestibility of total energy in the 20 GSPs group was significantly higher than that in the control group(P≤0.05).The digestible energy metabolic rate of the 10 GSPs group was significantly higher than that of the control group and 40 GSPs group(P≤0.05).the digestible energy metabolic rate of the 20 GSPs group was significantly higher than that of the control group(P ≤ 0.05).In conclusion,high-concentrate diet supplemented with appropriate amount of GSPs can improve the growth performance and slaughter performance of fattening lambs,and improve the meat quality,increase the utilization rate of nutrients and the anti-oxidation ability,GSPs can alleviate the oxidative stress of fattening lambs caused by high concentrate,which suggests that GSPs can be used as a natural feed additive in lamb production,and the recommended dietary supplementation level of GSPs is 20 mg/kg BW under the condition of this experiment.