山西白猪SLA-DQB基因多态性研究

为评价和选育山西白猪提供分子基础数据,采用PCR(polymerase chain reaction)-RFLP(restriction fragment length polymorphism)法对202头山西白猪SLA(swine leukocyte antigen)-DQB基因外显子2的273 bp扩增产物多态性进行研究.山西白猪经HaeⅢ酶切后产生6种基因型:167 bp/23 bp/29 bp/54 bp(AA)、84 bp/83bp/23 bp/29 bp/54 bp(BB)、167 bp/4 bp/102 bp(CC)、167 bp/23 bp/83 bp(EE)、167 bp/23 bp/29 bp/54 bp/4 bp/102 bp(AC)和167 bp/106 bp/4 bp/102 bp(CD);5种等位基因(A、B、C、D和E),其中等位基因A和基因型AA有明显优势.山西白猪SLA-DQB基因外显子2 HaeⅢ-RFLP带型较多.     

合作猪SLA-DQA基因第4外显子多态性分析

合作猪的MHC-DQA基因的适应性变异,其抗原识别区域(即外显子4)通过PCR扩增和随后的单链构象多态性(SSCP)和序列分析,结果显示在439个合作猪个体,SLA-DQA第4外显子检出4个等位基因和6个基因型(AA、BB、DD、AB、AC和AD),其中A等位基因和AA基因型的频率最高,为优势基因和优势基因型。对不同型的PCR-SSCP条带测序分析,发现7个突变位点(5 068 bp T→C,5 109 bp和5 149 bp处缺失C,5 131 bp A→G导致丝氨酸变为甘氨酸,5 135 bp C→T,5 234 bp G→A,5 136 bp处插入A)。遗传学分析发现,合作猪多态信息含量(PIC)为0.240 1,属于低度多态,各种基因型的分布不显著。研究结果证实,合作猪SLA—DQA基因第4外显子为低度多态。     

猪TLR4基因外显子1新等位基因的分离及遗传变异分析

文章采用PCR-SSCP方法对亚洲野猪、3个引进的商业化品种和10个中国地方猪品种共893个个体TLR4基因外显子1的遗传变异进行了检测,旨在系统分析国内外猪种TLR4基因的多态性,为探讨该基因在免疫和防御系统中发挥的作用提供依据。结果,在猪TLR4基因外显子1中分离到新的等位基因,共检测到3个等位基因,6种基因型。其中杜洛克检测到AA、BB、CC、AB、AC、BC基因型,有杜洛克血统的苏太猪中检测到BB、CC、BC基因型,长白猪、约克夏中检测到CC、BC基因型,野猪及所有10个中国地方猪品种TLR4基因外显子1高度保守,只检测到CC基因型,中国地方猪品种和引进品种TLR4基因外显子1多态性存在极显著的差异。3种基因型中CC型与GenBank中的序列一致,BB和AA基因型分别存在G93C同义突变位点和G194A无义突变位点,这2个变异位点与抗逆性和一般抗病力的关系值得进一步深入研究。     

五指山、二花脸和皮特兰猪的SLA-DRB基因外显子2 PCR-RFLP及PCR-SSCP多态性分析

采用PCR-RFLP法和PCR-SSCP法对17头五指山猪、28头二花脸猪以及28头皮特兰猪SLA-DRB外显子2进行分型。采用PCR-RFLP技术分型,结果显示：限制酶MspⅠ酶切可分出1种RFLP带,即M：143bp／102bp;限制酶RsaⅠ酶切可分出4种RFLP带,分别为A：141bp／93bp／11bp,B：111bp／69bp／54bp／11bp,C：180bp／54bp／11bp以及D：93bp／48bp／39bp／54bp／11bp。检测发现,五指山猪有2种RFLP带型：AA和BB,二花脸猪有3种RFLP带型：AA、BB和AB,皮特兰猪有3种RFLP带型：AA、CC和BD。比较五指山猪、二花脸猪与皮特兰猪,发现3个品种都是以A带为主,分别占到0．69、0．73和0．82,品种之间差别不显著。采用PCR—SSCP技术共分出7种标记带型,分别为αα、αδ、、ββ、γγ、αγ、δδ,βε,其中五指山猪有3种带型,分别为αα、αδ和ββ,二花脸猪有3种带型,分别为αα、γγ和αγ,而皮特兰则出现5种带型,分别为αα、δδ、αδ、βε和ββ。在3个品种猪中均存在α带,且其频率在各自品种中均最高,在五指山猪和皮特兰猪中δ带出现的频率次之,相应的在这两个猪种中杂合型αδ带型出现的频率则最高。Hardy-Weinberg平衡分析表明,二花脸猪SLA—DRB基因外显子2的RFLP带型达到平衡状态,其SSCP带型也达到平衡状态,五指山猪SLA—DRB基因外显子2的RFLP带型以及SSCP带型均未达平衡状态,皮特兰猪SLA—DRB基因外显子2的RFLP及SSCP带型大部分未达平衡状态。     

猪IGF-Ⅰ基因的一个遗传多态性及其遗传效应分析

采用PCR-SSCP方法对长白猪(87头)、大白猪(79头)和马身猪(102头)的胰岛素样生长因子-Ⅰ(IGF-Ⅰ)基因外显子3和外显子4分别进行单核苷酸多态性分析.发现外显子3上有多态性,且存在3种基因型(AA、AB、BB).统计结果表明,3种基因型在各品种中的分布不一致,多重比较差异极显著(P＜0.01).固定效应模型分析结果表明,背膘厚基因型间差异显著(P＜0.05),而初生重、断奶重和6月龄重基因型间差异不显著(P＞0.05).最小二乘分析结果表明,BB基因型与其它2种基因型比较有较大的初生重,同AA和AB型比较差异极显著(P＜0.01),3种基因型在初生重的大小排列顺序为AA＜AB＜BB;BB基因型与AA基因型比较有较小的背膘厚,且差异极显著(P＜0.01).因此,推测IGF-Ⅰ基因对个体的初生重和胴体瘦肉率存在一定的影响.选择带有B等位基因的个体,有望提高个体的初生重和胴体的瘦肉率.     

FSHβ 基因PCR-SSCP多态性及其与济宁青山羊高繁殖力关系的研究

采用PCR-SSCP技术检测促卵泡素b亚基(follicle-stimulating hormone β, FSHβ)基因5′调控区、外显子1和外显子2在高繁殖力山羊品种(济宁青山羊)和低繁殖力山羊品种(辽宁绒山羊、波尔山羊、安哥拉山羊)中的单核苷酸多态性, 同时研究该基因对济宁青山羊高繁殖力的影响。结果表明: 山羊与绵羊的FSHβ 基因该段核苷酸序列同源性为98%。9对引物中, 只有P9的扩增片段存在多态性。P9的扩增片段在济宁青山羊和辽宁绒山羊中检测到AA、AB和AC 3种基因型; 在波尔山羊中检测到AA、CC和AC 3种基因型; 在安哥拉山羊中检测到AA、BB、CC、AB、AC和BC共6种基因型。测序分析发现BB型与AA型相比在外显子2的第94 bp处有G→A突变, 并引起氨基酸改变(丙氨酸→苏氨酸); CC型与AA型相比在外显子2的第174 bp有一处C→T沉默突变。济宁青山羊AA、AB和AC基因型频率分别为0.686、0.137和0.177。AA基因型济宁青山羊产羔数最小二乘均值比AB基因型的多0.78只(P<0.05), 比AC基因型的多0.64只(P<0.05)。     

糯谷猪FSHβ基因多态性与部分繁殖性能的关系

采用PCR扩增技术对贵州地方猪品种糯谷猪的FSHβ亚基基因进行了检测,结果发现有2个等位基因A和B,3个基因型AA、AB和BB.各种基因型数量BB型>AB型>AA型,BB型为优势基因型,优势等位基因为B.分析3种基因型与部分繁殖性能之间的相关性,证明AB型的总产仔数显著高于AA型(P<0.05),AA型与BB型间差异不显著(P>0.05);BB型和AB型间差异不显著(P>0.05),说明AB型为优势基因型,而在其他性状之间没有发现显著的差异.因此FSHβ亚基基因可以作为控制猪高繁殖率的候选基因.     

猪产仔数分子标记及其效应分析

初步确定了2个新的猪产仔数分子标记,雌激素受体基因ESR的第8外显子处的ESRB位点、催乳素受体基因的第7外显子的FSHRB位点。通过比较和分析多个产仔数的效应,初步确定了4个有利于产仔数提高的分子标记基因型,基因位点ESR、FSHRB的基因型BB的产仔数显著地高于AB、AA型;位点ESRB、PRLR的基因型AA的产仔数显著地高于AB、BB型;4个基因位点多态性与仔猪生长性能、母猪乳头数不存在显著的影响。     

五指山猪GH、IGFBP3基因SNPs检测及与生长性状的关联分析

以五指山猪为试验材料,采用PCR-SSCP和测序相结合技术,对GH基因和IGFBP3基因进行多态性检测,并分析其与生长性状(体质量,体高,体长和胸围)的相关性。结果表明,GH基因第2外显子存在一处G→A转换,属沉默突变,该位点与生长性状关联分析显示,BB基因型的体重显著高于AA基因型和AB基因型;IGFBP3基因第2外显子存在一处G→C颠换,属沉默突变,该位点与生长性状关联分析显示,AA基因型的体高显著高于BB基因型;IGFBP3基因第4内含子存在一处碱基C缺失,该位点与生长性状关联分析显示,AA基因型体重显著高于AB基因型和BB基因型。研究将为五指山猪生长发育规律、系统选育及矮小机制等方面研究提供了遗传学依据。     

猪IGF2基因的遗传多态性及其遗传效应分析

采用PCR-SSCP方法检测胰岛素样生长因子2 (insulin-like growth factor 2, IGF2)基因外显子7, 8, 9的多态性, 并分析其对初生重、断奶重、6月龄重和6月龄背膘厚的遗传效应。根据猪IGF2基因的DNA序列(AY044828)设计3对引物, 结果在Ex8引物对扩增的片段上发现了多态性, 并对纯合子进行测序, 发现exon8的53位存在C→T转换, 且检测到3种基因型(AA、AB、BB)。统计结果表明, 3种基因型在各品种中的分布不一致, 长白猪与大白猪比较, 莱芜猪与大薄莲猪比较, 沂蒙黑猪和里岔黑猪比较差异不显著(P > 0.05); 其他猪种间基因型分布的差异均显著(P < 0.01)。固定效应模型分析结果表明, 初生重和6月龄背膘厚基因型间差异显著(P < 0.05), 而断奶重和6月龄重基因型间差异不显著(P > 0.05)。最小二乘分析结果表明, BB基因型个体同AA和AB基因型个体比较初生重的差异显著(P < 0.05), 3种基因型在初生重的大小排列顺序为AB > AA > BB; AA基因型个体同AB和BB基因型个体比较6月龄背膘厚的差异显著(P < 0.05), 3种基因型在6月龄背膘厚的大小排列顺序为BB > AB > AA。因此, 推测IGF2基因对个体的初生重和胴体瘦肉率存在一定的影响, 将IGF2基因应用于猪育种过程中的标记辅助选择可以加快猪的育种进程。     

Ovarian development in Meishan pigs

Ovaries collected from a total of 35 Meishan gilts of various ages were morphologically and histologically examined. Vesicular follicles were first observed in ovarian sections at 45 d of age. Simultaneously, protruding follicles appeared on the surface of the ovaries, and then ovarian weight increased rapidly with an increasing number of protruding follicles. About half of the gilts between 75 and 90 d of age had ovaries with corpora lutea, indicating that some of them had started estrous cycles before reaching 75 d of age. In Meishan gilts treated with exogenous gonadotropins, ovaries were stimulated as early as 45 d of age. These results suggest that the precocity of Meishan gilts may include the development of vesicular follicles in the ovaries at an early age.     

Testicular development in Chinese Meishan boars

The developmental process of the testis and age-related changes in the morphology of rete testicular spermatozoa were investigated in Meishan boars at 1 to 364 days of age. Testicular weight and the diameter of seminiferous tubules increased rapidly until 150 to 180 days of age. Leptotene stage spermatocytes, round spermatids and spermatozoa were first found in the section of seminiferous tubules at 30 to 45, 60 and 75 days of age, respectively. However, after 105 to 120 days of age, most rete testicular spermatozoa were morphologically normal. These results indicate that Meishan boars reach puberty as early as 75 days of age, though the testes acquire the ability to produce morphologically normal spermatozoa at about 120 days.     

Some new variants of serum protease inhibitors in Meishan pigs

Serum samples of Meishan (13 animals) and Meishan x Wild Boar crosses (361 animals) were analysed by means of two-dimensional electrophoresis. Some new variants in protease inhibitor systems PO1A, PO1B and PI2 are reported.     

Germ cell development in Meishan and White Composite gilts

This study compared dynamics of the germ cell population in two swine breeds that differ in prolifacy, White Composite (WC) and Meishan (MS), during fetal and neonatal life and in mature sows. Germ cell populations developed in a similar pattern in these two diverse breeds during fetal life. Maximal germ cell number was observed at 90 days postcoitum (dpc) in both WC and MS gilts, and substantial oogonial apoptosis was evident thereafter with approximately 30% of maximal numbers present at 25 days postpartum (dpp). Neither gilt nor sow germ cell number was correlated with maternal ovulation rate. Postnatal MS gilts had larger pools of primordial follicles and consistently greater proportions and numbers of primary and secondary follicles compared to postnatal WC gilts, indicative of enhanced follicular recruitment and primordial follicle activation. Occasional antral follicles were present in MS ovaries by 25 dpp and numerous surface follicles were observed at 56 dpp in MS but not WC ovaries, indicative of more rapid ovarian maturation and early onset of puberty. Total germ cell number is unlikely to influence or to predict subsequent ovulation rate. These observations highlight important developmental events during late fetal and early postnatal life that prepare the ovarian environment for early onset of puberty and subsequent ovulation in MS gilts.     

Comparison of the semen characteristics of Fengjing, Meishan and Yorkshire boars

Semen characteristics of Chinese Fengjing, CHinese Meishan and American Yorkshire boars were examined. Samples were collected from 24 boars: 6 Fengjing, 12 Meishan and 6 Yorkshire. Three semen characteristics and 6 biochemical evaluations of semen or seminal plasma were analyzed. The whole semen parameters measured were gelatinous (gel) and gel-free volume and progressive motility. Fengjing boars were higher in gel volume than Meishan (P < 0.05) but not Yorkshire boars (P > 0.25), while Yorkshire boars were higher than Meishan boars in gel volume (P < 0.10). The gel-free volume was higher in Yorkshire and Fengjing boars than Meishan boars (P < 0.10), but Fengjing gel-free volumes did not differ from Yorkshire gel-free volumes (P > 0.80). However, the only difference detected for progressive motility was between Fengjing and Meishan boars (78.5 vs 74.5%; P < 0.10). Sperm concentration was higher in Meishan than Yorkshire boars (P < 0.01) although these breeds did not differ from Fengjing boars (P > 0.18). The biochemical messurements made were fructose, galactose, inositol, total carbohydrate and total protein in seminal plasma and pH in gel-free semen. Fengjing boars had higher concentrations of galactose in seminal plasma than Meishan or Yorkshire boars (P < 0.05), while Meishan seminal plasma had higher galactose concentrations than Yorkshire seminal plasma (P < 0.10). Fructose, inositol and total carbohydrate concentrations were all higher in Fengjing and Meishan seminal plasma than Yorkshire seminal plasma (P < 0.05). Fengjing seminal plasma had higher levels of inositol than Meishan seminal plasma (769 vs 566 mg/100 ml; P < 0.10). Furthermore, Fengjing and Meishan semen had similar fructose and total carbohydrate concentrations (P > 0.80). The pH level and total protein concentration did not differ among the 3 breeds (P > 0.30). This study indicated that breed differences were detected for several seminal parameters, although no single breed had consistantly higher values for all the parameters measured.     

Conceptus development in large white and prolific Chinese Meishan pigs

Large White (LW) and Meishan (MS) gilts were killed on Days 8, 10, 11, 12, 14 and 30 of gestation. Mean diameters (mm) for MS and LW conceptuses, respectively, were: Day 8, 0.45 and 0.69; Day 10, 2.7 and 1.9; Day 11, 5.3 and 2.7, with the differences among days being affected by breed (P less than 0.01). Variation in diameter among conceptuses from LW gilts was greater (P less than 0.01) than that for MS gilts on Days 8-11, respectively: Day 8, 20 and 46%; Day 10, 29 and 38%; and Day 11, 22 and 44%. Conceptuses had elongated in 3 of 5 MS and 1 of 4 LW gilts on Day 11, 6 and 6 MS and 2 of 4 LW gilts on Day 12 and all gilts of both breeds on Day 14. These results indicate that conceptuses of MS gilts develop more rapidly and more uniformly between Days 8 and 14 of gestation. Overall, embryonic survival for Days 8-12 for gilts not having elongated conceptuses was 90.2% for MS and 73.2% for LW gilts (P less than 0.01). On Day 30 of gestation, embryonic survival was also higher (P less than 0.01) for MS (89%) than LW (55%) gilts. However, embryonic weight, crown-rump length, placental length, allantoic fluid volume, amniotic fluid volume, as well as total glucose, fructose and protein in allantoic fluid were not affected by breed. Placental weight was greater (P less than 0.01) for LW gilts. Uterine development at Day 30 of gestation, based on total length and weight of uterine horns, width of uterine horns, total endometrial surface area and total endometrial weight was greater (P less than 0.01) for LW gilts.(ABSTRACT TRUNCATED AT 250 WORDS)     

岷江眉山段四川华鳊年龄与生长

为了解我国长江上游特有鱼类四川华鳊Sinibrama taeniatus种群资源现状,于2013年3月至2014年1月在长江一级支流岷江眉山段采集了580尾四川华鳊样本,以鳞片作为鉴定材料,对其年龄和生长特征进行了研究。结果显示:四川华鳊鳞片年轮特征明显,表现为普通疏密型,为一年一个周期。研究样品的年龄由0~+~3~+(1~4龄)4个年龄组组成,其中以1~+~2~+龄(2~3龄)为主,占样品总量的96.07%。体长(L,m)和鳞径(R,mm)具有显著相关性雌、雄鱼差异无统计学意义(P0.05)表达式为L=25.45R+65.73。体质量(W,g)与体长呈幂函数相关,雌、雄鱼差异无统计学意义(P0.05),属等速增长,表达式为W=2.4×10~(-5)L~(2.94)(R~2=0.25)。Von Bertalanffy生长方程分别为:L_t=139.57×[1-e~(-0.15(t+3.16))],W_t=47.97×[1-e~(-0.15(t+3.16))]~(2.94),生长系数为0.15,拐点年龄为4.09龄,对应的体长和体质量分别为L_i=92.06mm,W_i=14.13g。岷江眉山段四川华鳊属于生长相对较快型鱼类。建议依法取缔非法捕捞工具,减少水电工程建设,这些措施对于保护四川华鳊种质资源有重要作用。     

小梅山猪Ghrelin基因的克隆及其在生殖轴的表达

以小梅山母猪为试验材料,通过RT-PCR、克隆及荧光定量,研究Ghrelin在其生长发育不同阶段生殖轴表达情况,旨在探究Ghrelin对动物繁殖性能的影响。结果表明,初生、初情期至性成熟卵巢Ghrelin mRNA表达量呈上升趋势,不同阶段间差异显著(P<0.05)。性成熟时生殖轴不同组织Ghrelin mRNA表达量,卵巢明显高于垂体和下丘脑(P<0.05),而垂体与下丘脑间差异则不显著(P>0.05)。