鸡Camk2d基因外显子15的SNP发现、检测及与经济性状的关联分析

克隆了鸡Camk2d基因的部分片段并发现Camk2d基因第15外显子51bp处有一C→T碱基转换的沉默突变,该突变位点具有VspI酶切多态,通过PCR-RFLP技术对我国乌骨鸡、鹿苑鸡、固始鸡、白耳鸡、仙居鸡、斗鸡和大骨鸡等7个不同地方品种鸡进行了基因型检测。结果表明:在7个品种中存在3种基因型(CC、CT、TT),χ2检验显示在各品种间基因型存在不同差异。同时在藏鸡,隐性白羽鸡,杂交鸡(藏♂×隐♀)和75%血液藏鸡[藏♂×(藏♂×隐♀)♀]群体中进行了基因-性状关联分析,结果表明,该SNP位点与腹脂存在极显著相关(P<0.01),与肌肉pH值显著相关(P<0.05)。     

鸡脂滴包被蛋白基因内含子5多态性与胴体及脂肪性状的相关性分析

本试验采用PCR-RFLP方法检测脂滴包被蛋白基因(perilipin,PLIN)在济宁百日鸡、汶上芦花鸡等5个地方鸡种和1个培育品系中的遗传多态性,并分析了多态位点不同基因型与鸡胴体及脂肪性状的相关性。结果发现,在6个供试群体中检测到1个Pst Ⅰ酶切突变位点,测序证实为新发现的鸡PLIN基因2224 bp处G→T突变,该突变位点在供试群体中共检测到两种基因型(A1A1和A1A2),等位基因A1在所有供试群体中均表现为优势等位基因。关联分析结果表明,PLIN基因2224多态位点对鸡胴体性状和脂肪性状影响均不显著(P＞0.05)。多重比较结果表明,A1A1基因型个体在胴体和脂肪性状上总体优于A1A2基因型个体,但各性状均值在两种基因型个体间差异均不显著(P＞0.05)。本研究结果表明,该位点不能作为鸡胴体和脂肪性状的有效分子标记。     

淮南麻黄鸡CRBP4基因多态性与早期产蛋性状和蛋品质的相关性

旨在探索CRBP4基因与淮南麻黄鸡产蛋性状和蛋品质的相关性,寻找可作为淮南麻黄鸡产蛋性状的重要分子标记.本研究利用PCR-SSCP技术和DNA测序技术对308只淮南麻黄鸡CRBP4基因遗传多态性进行检测及基因型分析,并对CRBP4基因的多态位点与早期产蛋性状和30周龄蛋品质进行相关分析.结果表明,在CRBP4基因exon2和exon3上存在3个突变位点,即C826T、C1240T和A1241G,其中C826T和A1241G导致了49 Se→4 9Leu和97 Ile→97Val突变,这3个突变位点都属于中度多态,基因型分布都处于Hardy-Weinberg平衡状态(P＞0.05).C826T位点与母鸡的开产蛋重呈显著相关,CC基因型有利于提高开产蛋重;构建的单倍型对开产蛋重的影响达到显著水平(P＜0.05).结果提示,CRBP4基因不同基因型和单倍型组合与淮南麻黄鸡开产蛋重存在相关性.     

鸡催乳素基因外显子5的多态性及Taq I位点与边鸡繁殖性状的相关性分析

研究采用DNA池直接测序法寻找边鸡催乳素基因外显子5区域的多态位点.用PCR-RFLP技术检测发现的Taq I位点在边鸡以及3个对照鸡品种(京海黄鸡、尤溪麻鸡和AA鸡)中的单核苷酸多态性,并与边鸡的繁殖性状进行相关性分析.结果表明:在外显子5区域检测到3个突变位点(C5749T、T5821C、C25956T).T5821C位点经Taq I酶切显示3种基因型(AA、AB和BB).在4个鸡品种中都以A等位基因为优势等位基因.最小二乘分析表明,边鸡3种基因型个体的繁殖性状无显著差异(P>0.05).     

鸡OBR基因第20外显子多态性与脂肪性状的相关研究

对鸡OBR基因的单链构象多态性进行检测,在第20 外显子发现了一个新的单核苷酸多态位点。克隆测序了2种纯合子片段,在第20外显子编码区的860位碱基确认了一个由T变为C的突变,编码的氨基酸由缬氨酸突变为丙氨酸。在一个地方鸡杂交群体中检验这一多态位点与脂肪性状的相关,建立固定效应模型进行最小二乘分析,对脂肪性状的不同基因型效应进行差异显著性检验。结果表明:试验群体中AA、AB、BB基因型频率分别为0.641、0.292和0.067。不同基因型对各组杂交肉鸡腹脂率、皮下脂肪厚、肌间脂宽和肌内脂肪含量的效应均不显著(P>0.05),说明这一外显子片段上的变异位点并不是导致脂肪性状产生差异的原因。此结果为进一步研究鸡OBR基因多态性及其功能提供参考,并为丰富基因图谱的标记提供理论依据。     

鸡OBR基因第20外显子多态性与脂肪性状的相关研究

对鸡OBR基因的单链构象多态性进行检测，在第20外显子发现了1个新的单核苷酸多态位点。克隆测序了2种纯合子片段，在第20外显子编码区的860位碱基确认了1个由T变为C的突变，编码的氨基酸由缬氨酸突变为丙氨酸。在1个地方鸡杂交群体中检验这一多态位点与脂肪性状的相关，建立固定效应模型进行最小二乘分析，对脂肪性状的不同基因型效应进行差异显著性检验。结果表明：试验群体中AA、AB、BB基因型频率分别为0．641、0．292和0．067。     

鸡催乳素基因外显子5的多态性及Taq Ⅰ位点与边鸡繁殖性状的相关性分析

研究采用DNA池直接测序法寻找边鸡催乳素基因外显子5区域的多态位点。用PCR-RFLP技术检测发现的Taq I位点在边鸡以及3个对照鸡品种(京海黄鸡、尤溪麻鸡和AA鸡)中的单核苷酸多态性,并与边鸡的繁殖性状进行相关性分析。结果表明:在外显子5区域检测到3个突变位点(C5749T、T5821C、C5956T)。T5821C位点经Taq I酶切显示3种基因型(AA、AB和BB)。在4个鸡品种中都以A等位基因为优势等位基因。最小二乘分析表明,边鸡3种基因型个体的繁殖性状无显著差异(P>0.05)。     

线粒体DNA COX3基因多态性与瓢鸡生长和屠体性状的相关性分析

采用DNA测序和PCR-RFLP方法,分析了瓢鸡线粒体DNA COX3基因(mt DNA COX3)变异,并与生长和屠体性状进行了关联分析。在瓢鸡线粒体DNA COX3基因发现C10669T多态位点,建立了Eco RV PCR-RFLP分子标记,利用该标记对300日龄具有生长和屠体性状记录的82只瓢鸡进行了基因分型。结果表明,线粒体DNA COX3基因C10669T多态位点在瓢鸡群体中C基因为优势基因,基因频率为69.5%,多态信息含量和杂合度分别为0.3341与0.4240。C10669T位点基因型在体重、龙骨长、跖长、屠体重与胸肌率5个性状差异显著,C基因型个体普遍高于T基因型。线粒体DNA COX3基因对瓢鸡生长和屠体性状的作用机理有待进一步深入分析。     

北京油鸡喙畸形性状候选基因GLA多态性的研究

本实验旨在研究α-半乳糖苷酶(GLA)基因的多态性及其与北京油鸡喙畸形性状之间的关系。用直接测序的方法检测GLA基因的单核苷酸多态性。结果表明:该基因启动子的-524、-389、-242、-212 bp处,内含子6的4 494、4 505、4 552、4 691 bp处以及外显子7的4 815 bp处共发现9个突变位点。卡方检验显示,所有位点均符合Hardy-Weinberg平衡(P0.05)。群体遗传多态性结果显示,正常鸡所有位点为中度多态(0.25PIC0.5);喙畸形鸡中,C4494T、G4505A、C4691T 3个位点为低度多态(PIC0.25),其余位点为中度多态(0.25PIC0.5)。基因型差异比较发现,在外显子7的C4815T位点处,喙畸形鸡未发生突变,与正常鸡基因型差异显著(P0.05);在内含子6的A4552C位点处,正常鸡AA型频率较高,喙畸形鸡CC型频率较高,两者基因型差异极显著(P0.01),其余位点差异不显著(P0.05)。结果提示,GLA基因的多态性与喙畸形存在一定关联,C4815T和A4552C 2个位点的SNPs有望成为剔除喙畸形性状的潜在遗传标记。     

鸡PRR5L基因5'UTR多态性及其与脂肪性状、屠体性状的关联分析

试验旨在研究类富脯氨酸5（proline rich 5 like，PRR5L）基因遗传变异对鸡脂肪性状及屠体性状的影响。以矮脚黄鸡为研究对象，根据GenBank公布的鸡PRR5L基因全序列（登录号：XM_015287209.1）设计扩增引物，利用PCR直接测序技术检测PRR5L基因的5'UTR区域单核苷酸多态性（SNPs），并用统计学方法分析其与鸡脂肪性状及屠体性状的关联性。结果发现，PRR5L基因5'UTR区域存在C480G、G514A和A579G 3个多态位点，均表现出3种基因型。χ²适合性检验结果发现，群体在G514A位点处于Hardy-Weinberg非平衡状态（P < 0.05）；在C480G和A579G位点均处于Hardy-Weinberg平衡状态（P > 0.05）。基因型与性状关联分析结果显示，在脂肪性状方面，PRR5L基因3个多态位点各基因型间腹脂重、腹脂率和肌内脂肪含量差异均不显著（P > 0.05）；在屠体性状方面，在G514A位点处AG与GG基因型的胸肌重差异显著（P < 0.05），其余指标差异均不显著（P > 0.05）。因此，可推断PRR5L基因5'UTR的G514A位点可能是一个影响鸡胸肌生长发育的位点，但该位点能否作为标识鸡屠体性状的分子标记辅助选择还需要进一步探究。     

Scrapie in goats in Cyprus

Ovine scrapie was first recorded in Cyprus in 1985. Subsequently four dairy goats kept in two mixed flocks with affected sheep developed characteristic clinical signs similar to those seen in sheep. Fifteen goats from the two flocks were examined histologically and neurological lesions consistent with a diagnosis of scrapie were found in the four animals and in three others which had subsequently developed early neurological signs. These lesions were similar to those of naturally-affected sheep although neuronal degeneration and vacuolation were more severe in some cases.     

Heartworm in dogs in Canada in 1984

In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.

Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.

     

Heartworm in dogs in Canada in 1988

In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%).     

Heartworm in dogs in Canada in 1985

In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).

Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1989

In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.

Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.

     

Heartworm in dogs in Canada in 1986

In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).

Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1987

In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%).