摘要
牦牛低海拔舍饲是解决藏区草畜矛盾的重要手段,同时也能促进冷季牦牛生长发育,改善牦牛肉品质。旨在探讨低海拔区域开展牦牛舍饲模式对牦牛生长发育、屠宰性能、肌肉品质以及血清指标的影响,初步探索低海拔舍饲影响牦牛肌肉品质的可能因素。选用10头36月龄体重、体况相近的健康公牦牛,随机均分为舍饲组与放牧组,舍饲组于广汉农区(海拔:600 m)进行全舍饲育肥,放牧组于红原县牦牛科技园区(海拔:3500 m)按传统模式天然放牧,试验期150 d。结果表明,舍饲牦牛增重极显著高于放牧组(P<0.01),其胴体重、净肉重、屠宰率和净肉率极显著高于放牧组(P<0.01)。舍饲组背最长肌食用品质显著改善:亮度(L^*)显著高于放牧组(P<0.05),熟肉率和肌内脂肪(IMF)含量显著高于放牧组(P<0.05),剪切力显著低于放牧组(P<0.05);舍饲组背最长肌营养品质显著改善:粗脂肪(EE)含量极显著高于放牧组(P<0.01)。舍饲组棕榈酸(C16:0)、硬脂酸(C18:0)含量极显著高于放牧组(P<0.01);饱和脂肪酸(SFA)、多不饱和脂肪酸(PUFA)和反式脂肪酸(TFA)含量均显著高于放牧组(P<0.05)。鲜味氨基酸(FAA)显著高于放牧组(P<0.05)。血清指标分析结果显示,舍饲组血清中血糖(GLU)显著高于放牧组(P<0.05),甘油三酯(TG)、总胆固醇(TC)的含量极显著高于放牧组(P<0.01),β-羟基丁酸(BHBA)含量极显著低于放牧组(P<0.01);乙酰辅酶A羧化酶(ACC)活性极显著高于放牧组(P<0.01),脂肪酸合成酶(FAS)活性显著高于放牧组(P<0.05);激素敏感性脂肪酶(HSL)活性显著低于放牧组(P<0.05)。由此可见,通过冷季低海拔舍饲可达到牦牛生长肥育的效果;可激活牦牛血清中脂沉积相关酶活性,促进肌肉中脂肪的合成与沉积,改善牦牛肉食用品质及营养品质。
Indoor feeding of yaks at low altitude is an important means to overcome the winter forage supply problem for the large numbers of livestock in the Tibetan region,and it can also facilitate the growth and development of yak during the cold season and the improve the quality of yak meat.The purpose of our study is to explore the effects of indoor feeding in low-altitude areas on yak growth and development,slaughter performance,muscle quality,and serum indicators,and to provide preliminary data on factors that may influence yak muscle quality when indoor-feeding at low-altitude.Ten healthy 36-month-old male yaks of similar body weight and physical condition at 36 months of age were randomly divided into an indoor-feeding group and a grazing group.The indoor-feeding group were housed for fattening at Guanghan agricultural area(altitude:600 m),and the grazing group were naturally grazed following traditional yak farming practice at 3500 m altitude in Hongyuan County.The experiment duration was 150 days.It was found that the weight gain of yaks fed indoors was significantly higher than that of the grazing group(P<0.01),and the yak carcass weight,pure meat weight,dressing-out percentage which means ratio of carcass weight to live weight and pure meat percentage were all significantly higher than that of the grazing group(P<0.01).The dietary quality of the longissimus muscle in the indoor-feeding group was significantly improved:The brightness(L*)was significantly higher than that in the grazing group(P<0.05),the cooking percentage which is also known as cooking loss and intramuscular fat content were significantly higher than those in the grazing group(P<0.05),and the shear force was significantly lower than the grazing group(P<0.05).The nutritional quality of the longissimus dorsi muscle in the indoor-feeding group was also significantly improved:The ether extract content was significantly higher than that in the grazing group(P<0.01).The contents of palmitic acid(C16:0)and stearic acid(C18:0)in the indoor-feeding group were extremely high compared to the grazing group(P<0.01),and the contents of saturated fatty acids,polyunsaturated fatty acids,and trans fatty acids were significantly higher than those in the grazing group(P<0.05).The flavor-forming free amino acid levels were significantly higher in the indoor-feeding group than in the grazing group(P<0.05).For serum indicators,the blood glucose concentration in the indoor-feeding group was significantly higher than that in the grazing group(P<0.05),while increase in triglyceride and total cholesterol levels,compared to the grazing group were highly significant(P<0.01).The concentration ofβ-hydroxybutyric acid was significantly lower than the grazing group(P<0.01);the acetyl CoA carboxylase enzyme activity was higher than the grazing group(P<0.01);the fatty acid synthetase enzyme activity was significantly higher than the grazing group(P<0.05);and the hormone-sensitive lipase(HSL)enzyme activity was significantly lower than the grazing group(P<0.05).The test results show that yak weight gain and fattening can be achieved by indoor feeding at low altitude in the cold season.Through activation of serum enzyme activity related to lipid deposition in yak,indoor-feeding can facilitate the synthesis and deposition of fat in muscle and improve the dietary quality and nutritional quality of yak meat.
作者
杨勤
官久强
柴志欣
李华德
曹诗晓
张翔飞
柏琴
钟金城
罗晓林
YANG Qin;GUAN Jiu-qiang;CHAI Zhi-xin;LI Hua-de;CAO Shi-xiao;ZHANG Xiang-fei;BAI Qin;ZHONG Jin-cheng;LUO Xiao-lin(Sichuan Academy of Grassland Science, Chengdu 611731, China;Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Sichuan Province and Ministry of Education, Southwest Minzu University, Chengdu 610041, China)
出处
《草业学报》
CSCD
北大核心
2020年第5期33-42,共10页
Acta Prataculturae Sinica
基金
国家十三五重点研发计划项目(2018YFD0502304)
国家肉牛牦牛产业技术体系(CARS-37)
四川省科技支撑计划项目(16ZC2530)
第二次青藏高原综合科学考察研究项目(2019QZKK0302)资助。
关键词
低海拔舍饲
牦牛
肌肉品质
血清指标
脂沉积相关酶
low-altitude house-feeding
yak
muscle quality
serum index
lipid deposition-associated enzymes
