摘要
研究旨在评估日粮中添加不同比例的黑麦草对肉牛生长性能、营养物质消化、瘤胃发酵以及胴体与肉品质的效应。试验选取36头健康且体重相近[(450±15)kg]的西门塔尔杂交阉牛,随机分为3组,每组12个重复,每个重复1头牛。对照组(CON)饲喂全混合日粮(TMR),其基础粗饲料由羊草和玉米秸秆组成(分别占TMR的25%和15%);试验组T1和T2分别用黑麦草替代20%和40%的上述基础粗饲料。试验包括15 d预试期与90 d正试期。结果表明:1)生长性能:各组肉牛的末重(FBW)和平均日增重(ADG)无显著差异(P > 0.05),但T2组的干物质采食量(DMI)显著高于CON组(P<0.05)。2)消化性能:各组的干物质(DM)、粗蛋白(CP)、中性洗涤纤维(NDF)与酸性洗涤纤维(ADF)的表观消化率均无显著变化(P > 0.05)。3)瘤胃发酵:T1和T2组的瘤胃液氨态氮(NH3-N)浓度极显著低于CON组(P<0.01);同时,T2组的总挥发性脂肪酸(TVFA)浓度和乙酸/丙酸值显著高于CON组(P<0.05)。4)肉品质:与CON组相比,T2组牛肉的背最长肌剪切力值显著降低(P<0.05),肉色a*值(红度)显著提高(P<0.05);此外,T2组肌肉中多不饱和脂肪酸(PUFA)比例与ω-3脂肪酸含量均极显著提高(P<0.01),ω-6/ω-3值显著降低。结论 :用黑麦草替代40%基础粗饲料可在维持肉牛生长性能和营养物质消化的同时,优化瘤胃发酵模式,并显著改善牛肉的嫩度、肉色及脂肪酸组成,提高其营养价值。
This study was conducted to evaluate the effects of dietary inclusion of perennial ryegrass at different substitution levels on growth performance,nutrient digestibility,rumen fermentation,carcass traits,and meat quality in beef cattle.Thirty-six healthy Simmental crossbred steers with similar body weight(450±15 kg)were randomly assigned to 3 groups with 12 replicates per group and one steer per replicate.The control group(CON)was fed a total mixed ration(TMR),wherein the basal roughage consisted of Chinese wildrye and corn stover(constituting 25%and 15%of the TMR,respectively).The treatment groups T1 and T2 were fed diets in which perennial ryegrass replaced 20%and 40%of the aforementioned basal roughage,respectively.The experiment consisted of a 15-day adaptation period followed by a 90-day experimental period.The results showed that:1)Growth performance:Final body weight and average daily gain did not differ significantly among all groups(P>0.05);however,dry matter intake was significantly higher in the T2 group compared to the CON group(P<0.05).2)Digestive performance:No significant differences were observed in the apparent digestibility of dry matter,crude protein,neutral detergent fiber,or acid detergent fiber among the groups(P>0.05).3)Rumen fermentation:The concentration of ruminal ammonia-nitrogen was significantly lower in the T1 and T2 groups than in the CON group(P<0.01).Concurrently,the T2 group exhibited significantly higher total volatile fatty acid concentration and acetate-to-propionate ratio compared to the CON group(P<0.05).4)Meat quality:Compared to the CON group,the Warner-Bratzler shear force value of the longissimus thoracis muscle was significantly lower(P<0.05),and the a*value(redness)was significantly higher(P<0.05)in the T2 group.Furthermore,the proportion of polyunsaturated fatty acids and the content ofω-3 fatty acids in the muscle were significantly increased(P<0.01),and theω-6/ω-3 ratio was significantly reduced in the T2 group.In conclusion,replacing 40%of the basal roughage with perennial ryegrass can optimize the rumen fermentation pattern while maintaining growth performance and nutrient digestibility,and significantly improves beef tenderness,meat color,and fatty acid profile,thereby enhancing its nutritional value.
作者
张妍
黄雷
张金合
ZHANG Yan;HUANG Lei;ZHANG Jinhe(Hebei Tourism Vocational,College of Animal Husbandry and Veterinary Medicine,Chengde,Hebei Province 067000,China;Chengde City Beefattle Health Breeding Research Center,Chengde,Hebei Province 067000,China)
出处
《中国饲料》
北大核心
2025年第22期121-124,共4页
China Feed
关键词
黑麦草
肉牛
消化率
瘤胃发酵
肉品质
脂肪酸
perennial ryegrass
beef cattle
digestibility
rumen fermentation
meat quality
fatty acids
