【作者】 姚新奎；

【导师】 雒秋江；

【作者基本信息】 新疆农业大学 ， 动物营养与饲料科学， 2011， 博士

【摘要】 本文以昭苏马场伊犁马、新吉尔吉斯马(以下简称新吉马)及其杂交马为研究对象,主要研究了三种马马乳的的理化指标、泌乳规律、各组分与泌乳特性的相关性、体尺与泌乳的相关性、PRL和PRLR基因多态性。其结果如下：理化指标研究：测定和分析了伊犁马和杂交马初乳总蛋白含量和免疫球蛋白的动态变化,伊犁马、新吉马及其杂交马常乳中的蛋白的变化规律,以及伊犁马常乳中氨基酸的种类和含量。结果显示：(1)伊犁马和杂交马初乳中的蛋白质高于常乳,随着泌乳期的延长而逐步接近常乳,在产驹后12h内急剧下降。(2)在相同泌乳阶段,伊犁马初乳中的乳蛋白与杂交马存在差异,表现为伊犁马的大部分时期值高于杂交马,随着泌乳期的延长,差异变得越来越小。(3)初乳中蛋白质含量,在产后4h里,伊犁马极显著性高于杂交马(P<0.01),在产后72h内,伊犁马显著性高于杂交马(P<0.05)。(4)杂交马和伊犁马IgG的含量在产驹后各个时间段中差异不大,但伊犁马的含量要高于杂交马。IgG的含量在产驹后6h内剧烈下降,故让新生马驹尽早吃上初乳尤为重要。(5)伊犁马、新吉马及其杂交马三者常乳中蛋白差异不显著。(6)各个品种常乳蛋白含量在泌乳周期内存在一定差异,但差异不明显。(7)伊犁马常乳属于完全蛋白质,具有良好的氨基酸比例和含量。(8)伊犁马常乳富含组氨酸、谷氨酸、天冬氨酸、蛋氨酸、精氨酸。测定和分析了伊犁马和杂交马初乳脂肪含量的动态变化,伊犁马、新吉马及其杂交马常乳中的脂肪变化规律,以及伊犁马初乳和常乳中脂肪酸的种类和含量。结果显示：(1)伊犁马和杂交马初乳脂肪含量均在产后24h达到了最高值,在产后第96h后基本趋于稳定。(2)两种马初乳的脂肪变化趋势为先升高后降低,伊犁马的变动区间大于杂交马。(3)伊犁马、新吉马及其杂交马三者常乳中脂肪差异不显著。(4)各个品种常乳脂肪含量在泌乳周期内存在一定差异。(5)马奶中不饱和脂肪酸的的含量要高于牛奶等常见乳品。(6)马奶含有丰富的中链脂肪酸。(7)马奶还有一定量的奇数和支链脂肪酸,尤其是初乳中含量较高。(8)马奶中含有丰富的必需脂肪酸,说明马奶较常见乳品更优。测定和分析了伊犁马和杂交马初乳灰分含量的动态变化,伊犁马、新吉马及其杂交马常乳中的灰分和初乳中矿物质的变化规律。结果显示：(1)伊犁马和杂交马初乳中的灰分高于常乳,随着泌乳期的延长而逐步接近常乳,在产驹后12h内急剧下降。(2)在相同泌乳阶段,伊犁马初乳中的灰分与杂交马存在差异,表现为伊犁马的大部分时期值高于杂交马,随着泌乳期的延长,差异变得越来越小。(3)在产后前72h,伊犁马初乳中的灰分显著高于杂交马(P<0.05)。(4)伊犁马、新吉马及其杂交马三者常乳中灰分差异不显著。(5)各个品种常乳灰分含量在泌乳周期内存在一定差异,但差异不明显。(6)矿物元素含量要低于常见乳品。测定和分析了伊犁马和杂交马初乳密度、电导率、非脂固形物的动态变化,伊犁马、新吉马及其杂交马常乳中的密度、电导率、非脂固形物的变化规律。结果显示：(1)伊犁马和杂交马初乳中的密度、电导率、非脂固形物高于常乳,随着泌乳期的延长而逐步接近常乳。(2在相同泌乳阶段,伊犁马初乳中的密度、电导率、非脂固形物与杂交马存在差异,表现为伊犁马的大部分时期值高于杂交马,.随着泌乳期的延长,差异变得越来越小。(3)在产后前72h,伊犁马初乳中的密度显著高于杂交马(P<0.05)。(4)伊犁马和杂交马非脂固形物的含量在产驹后12h内急剧下降。(5)伊犁马、新吉马及其杂交马三者常乳中密度、非脂固形物差异不显著。(6)各个品种常乳密度、非脂固形物在泌乳周期内存在一定差异,但差异不明显。(7)伊犁马常乳电导率的变化规律与杂交马和新吉马差异较大,伊犁马高于杂交马和新吉马。泌乳规律及性状间相关性研究：测量了伊犁马、新吉马及其杂交马三者产驹后150d的产奶量,分析三者的泌乳规律。结果显示：(1)新吉马的产奶量显著性高于杂交马和伊犁马,杂交马的产奶量显著性高于伊犁马。(2)新吉马的泌乳规律呈现先高后低的趋势,伊犁马和杂交马的泌乳规律接近,前期相对平缓,后期逐渐下降,三种马在产驹80d后产奶量急剧下降。(3)杂交马的乳用性能较伊犁马和新吉马来说不稳定。测量了伊犁马、新吉马及其杂交马三者泌乳期的产奶量及三种马的体尺指标,并分析了各组分含量、体尺指标与泌乳量的相关关系。结果显示：(1)产奶量与乳脂量、乳蛋白量、乳非脂固形物量存在极强的正相关关系；产奶量与乳脂率存在极强的正相关关系,与乳蛋白率没有相关关系,与乳非脂固形物率存在极强的负相关关系。(2)产奶量与体高、体长、胸围、管围均存在正相关关系,产奶量与胸围率、体躯指数存在正相关,产奶量与体长率、管围率没有相关关系。PRL和PRLR基因多态性极其与产奶量的相关性：测定了伊犁马、新吉马及其杂交马三者PRL和PRLR基因多态性,并分析了PRL/PRLR突变基因型频率、PRL/PRLR不同基因型序列、多态性与产奶量的相关性。结果显示：(1)PRL基因第4外显子区域未检测到多态,在第5外显子区域检测到多态,在所研究的群体中共发现4·种基因型,外显子5等位基因在654bp处发生了一个C→T突变,591bp处发生了一个T→G突变。通过对编码的氨基酸进行分析发现,碱基突变均未导致氨基酸的改变。(2)PRLR基因第3、10外显子区域未检测到多态,只在第4外显子区域检测到多态,在所研究的群体中共发现2种基因型,外显子4等位基因在156 bp处发生了一个C→T突变。通过对编码的氨基酸进行分析发现,碱基突变均未导致氨基酸的改变。(3)伊犁马群体内,PRL和PRLR基因不同基因型之间产奶量有显著和极显著差异,但是在新吉马和杂交马群体内,不同基因型个体之间产奶量差异不显著。更多还原

【Abstract】 This article mainly studied chemical-physical indicators, lactation charactor, correlation between milk yield and milk composition, correlation between milk yield and body measurement, polymorphism of PRL and PRLR gene of Yili horse New Kirgiz horse and Hybrid horse in the Zhaosu Stud. The result is as follow:Chemical-physical indicators:Content of total protein and IgG in colostrum between Yili horse and Fl hybridization mare of new Kirghiz horse and Yili horse, protein in milk of Yili horse New Kirgiz horse and Hybrid horse, the type and content of amino acids in milk of Yili horse were compared and analyzed. The results showed that:(1)Protein in colostrum of Yili horse and hybrid horse was higher than that in milk, and gradually close to milk with the extension of lactation, and decreased dramatically in 12h after foaling. (2) Protein in Yili horse colostrum were different with hybrid horse at the same lactation period, as most measured values of Yili horse were higher than hybrid horse, and the difference was gradually narrowing with extended lactation period. (3) Protein in colostrum of Yili horse after foaling in 4 h were extremely significantly higher than that in hybrid horse (P<0.01), significantly higher than that in hybrid horse after foaling in 72 h (P<0. 05).(4) The difference of IgG content in Hybrid horse and Yili horese after foaling at given time internal, but the IgG content of Yili horse was higher than Hybrid horse. Contents of IgG declined sharply after foaling within 6h, so it is particularly important to let new foal eat colostrum as soon as possible.(5) Protein of three mare breeds was non-significant. (6) Protein of every breeds was non-significant in the lactation period.(7) Content and ratio of amino acids in mare’s milk was appropriate. (8)Milk of Yili hores was rich of His, Glu, Asp, Met, Arg,Fat in colostrum between Yili horse and Fl hybridization mare of new Kirghiz horse and Yili horse, fat in milk of Yili horse New Kirgiz horse and Hybrid horse, the type and content of fatty acids in milk of Yili horse were compared and analyzed. The results showed that:(1)Fat in colostrum of Yili horse and hybrid horse reached maximum value at 24h after parturition, and were were stable after foaling in 96 h.(2) Trend in colostrum of two horse breed were first increased and then decreased, and change Interval of Yili horse was bigger than Hybrid horse. (3) Fat of three mare breeds was non-significant. (4) Fat of every breeds has some difference between different moments in the lactation period. (5) The content of unsaturated fatty acids of mare’s milk was higher than other common dairy. (6) Mare’s milk is rich in medium-chain fatty acids, so it have some health and medical capabilities. (7) There is a certain amount of OBCFA in mare’s milk, especially in the colostrum. (8)Mare’s milk was superior to other common dairy, because it was rich of EFA.Ash in colostrum between Yili horse and Fl hybridization mare of new Kirghiz horse and Yili horse, ash in milk of Yili horse New Kirgiz horse and Hybrid horse, minerals in colostrum of Yili horse New Kirgiz horse and Hybrid horse were compared and analyzed. The results showed that:(1)Ash in colostrum of Yili horse and hybrid horse was higher than that in milk, and gradually close to milk with the extension of lactation, and decreased dramatically in 12h after foaling.(2)Ash in Yili horse colostrum were different with hybrid horse at the same lactation period, as most measured values of Yili horse were higher than hybrid horse, and the difference was gradually narrowing with extended lactation period.(3)Ash in colostrum of Yili horse was significantly higher than that in hybrid horse after foaling in 72 h (P<0.05). (4) Ash of three mare breeds was non-significant. (5) Ash of every breeds was non-significant in the lactation period.(6) Content of minerals was less than other common dairy, but the ratio between minerals in mare’s milk was appropriate.Density, non-fat solids, electrical conductivity in colostrum between Yili horse and Fl hybridization mare of new Kirghiz horse and Yili horse, density, non-fat solids, electrical conductivity in milk of Yili horse New Kirgiz horse and Hybrid horse were compared and analyzed. The results showed that:(1) Density, non-fat solids, electrical conductivity in colostrum of Yili horse and hybrid horse was higher than that in milk, and gradually close to milk with the extension of lactation.(2) Density, non-fat solids, electrical conductivity in Yili horse colostrum were different with hybrid horse at the same lactation period, as most measured values of Yili horse were higher than hybrid horse, and the difference was gradually narrowing with extended lactation period.(3) Density in colostrum of Yili horse significantly higher than that in hybrid horse after foaling in 72 h (P<0.05). (4) Non-fat solids decreased dramatically in 12h after foaling.(5) Density, non-fat solids of three mare breeds was non-significant. (5) Density, non-fat solids of every breeds was non-significant in the lactation period.(6) Variation of electrical conductivity of Yili horse was different of the Yili horse, and the absolute value of Yili horse was high.Regulation of lactation and Correlation:Milk yield and body measurement of Yili horse New Kirgiz horse and Hybrid horse was determined, and correlation between milk yield and milk composition, body measurement was analyzed. The results showed that:(1)The milk yield of New Kirgiz horse was extremely significantly higher than Hybrid horse,and Hybrid horse was extremely significantly higher than Yili horse. (2)The regulation of lactation of New Kirgiz horse was first high to low. The regulation of lactation of Hybrid horse, pre relatively flat and decreasing late was similar to Yili horse. Milk yield of three mare breed decrease fast in 80d after parturition. (3)Comparing with Yili horse and New Kirgiz horse, lactation charactor of Hybrid horse was unstable. (4)There is a strong positive correlation between milk yield and content of fat, non-fat solids, protein. Correlation between milk yield and fat percentage was very strong positive, no correlation between milk yield and protein percentage,and negative correlation between milk yield and non-fat solids percentage. (5) There is a strong positive correlation between milk yield and height at withers,body length,heart girth,circumference of cannon bone. Correlation between milk yield and chest girth ratio, trunk index was very strong positive, no correlation between milk yield and body length ratio, shank circumference ratio.Polymorphism of PRL and PRLR gene and correlation:PRL and PRLR gene polymorphism of three breeds were determined, and genotype frequency distribution, base sequence of different genotypes, correlation between polymorphism and milk yield was analyzed. The results showed that:(1)Polymorphism of PRL exon 5 was detected in the 4 genotypes which was studied, but PRL exon 4 was not。Mutation of PRL exon 5 occurred at 591bp(T→G)and 654bp(C→T)。By analyzing codon of amino acid, we found that mutation do not cause the change of amino acid.(2)Polymorphism of PRLR exon 4 was detected in the 2 genotypes which was studied, but PRL exon 3,10 was not.Mutation of PRL exon 4 occurred at 156bp(C→T)。By analyzing codon of amino acid, we found that mutation do not cause the change of amino acid。(3) There were significant and extremely significant differences between milk yield of different genotypes of Yili horse, but there were no differences of New Kirgiz horse and Hybrid horse.更多还原