不同胎次草地藏系绵羊乳营养成分、酶活力及蛋白组分的研究  

Study on Nutrient Composition,Enzymatic Activities and Protein Components in Tibetan Sheep Milk of Different Births

作　　者：王永[1] 郑玉才[2] 梁梓[2] 吕程[2] 刘鲁蜀[2] 金素钰[2] 胡瑜[3] 傅昌秀[4] 陶永平[3] 

机构地区：[1]甘肃农业大学动物科学技术学院,甘肃兰州730070 [2]西南民族大学生命科学与技术学院,四川成都610041 [3]四川省若尔盖县畜牧局,四川若尔盖624500 [4]四川省畜禽繁育改良总站,四川成都610041

出　　处：《家畜生态学报》2006年第6期148-152,共5页Journal of Domestic Animal Ecology

基　　金：四川省十五攻关项目(02NG004-056);国家民委重点项目(03N010)的部分内容

摘　　要：对不同胎次草地藏系绵羊乳营养成分含量、乳酶活力及乳蛋白组分进行了研究。结果表明：草地藏系绵羊乳蛋白平均含量为48．45±13．21g／L，乳糖平均含量为41．93±5．06g／L，乳脂肪平均含量为69．43±11．41g／L。乳蛋白含量第二胎显著高于第一胎（P〈0．05），第四胎极显著高于第一胎（P〈0．01）；不同胎次间乳糖含量差异不显著（P〉0．05）；乳脂含量随着胎次增加呈下降趋势，第一胎乳脂含量显著高于第四胎（P〈0．05）。乳中γ-谷氨酰转肽酶（γ-GT）、碱性磷酸酶（AKP）、过氧化物酶（LP）和淀粉酶（AMY）的活力分别为268．25±89．18U／100mL、231．85±107．38U／100mL、3．97±3．68U／mL和80．65±73．91U／100mL；γ-GT的活力在不同胎次间未见明显变化（P〉0．05），而AKP和LP的活力在不同胎次间虽有的变化，但差异不明显（P〉0．05）。乳蛋白主要包括α-乳清蛋白（α-La）、β-乳球蛋白（β-Lg）、酪蛋白（CN）、免疫球蛋白（IgG）等组分。其中酪蛋白的相对含量约50％～52%，优势明显；α-La相对含量较低。不同胎次间主要蛋白组分相对含量差异不显著（P〉0．05）。对乳上皮粘蛋白（MUC1）研究发现它有4种分子量类型，分子量分别为214kD、209kD、207kD、205kD。The nutrient composition, enzyme activities and protein components were studied in Tibetan sheep milk of different births. The results showed that the contents of milk protein, lactose and fat were 48.45±13.21g/L, 41.93±5.06g/L, and 69.43±11.41g/L, respectively; the milk protein contents of 2nd and 4th birth ewe were higher than that of 1st birth ewe significantly（ P〈0.05 ）and very significantly（ P〈0.01 ） ; the differences of lactose content in milk of different births were insignificant （ P〉0.05 ） ; the content of fat were decreasing along with the increasing of births; the milk fat contents of 1st birth ewe were higher than that of 4th birth ewe significantly （ P〈0.05 ）. The activities of γ-glutamyl transpeptidase（γ-GT）, alkaline phosphatase （AKP）, lactoperoxidase （LP）, and amylase （AMY） in milk were 268.25±89. 18U/100mL, 231. 85±107.38U/100mL, 3. 97±3. 68U/mL, and 80.65±73. 91U/ 100mL, respectively. The differences of activity of γ-GT,AKP and LP in milk of different births were insignificant（ P 〉 0.05 ）. Main protein components in milk comprised α-lactalbumin（α-La）, β-1actoglobulin （β-Lg）, IgG, casein（CN） et al, the relative percentage of CN was 50%-52% approximately, but the relative content of α-Lα was low. The relative percentage of main protein components in milk were insignificant（ P〉0.05 ）in different births. Four kinds of molecular weight type of milk mucin 1 （MUC1）were discovered in this study, with molecular weights of 214 kD, 209 kD, 207 kD and 205 kD, respectively.

关 键 词：草地藏系绵羊 乳 营养成分 酶活力 蛋白组分 

分 类 号：S811.5[农业科学—畜牧学]