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 5like,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A579G3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(P0.05);在C480G和A579G位点均处于Hardy-Weinberg平衡状态(P0.05)。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(P0.05);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(P0.05),其余指标差异均不显著(P0.05)。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。     

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。     

鹌鹑FATP1、TBC1D1基因多态性及其与屠宰性状的关联分析

FATP1和TBC1D1基因在禽类糖类代谢和脂肪代谢中扮演着重要的角色,在家禽选育过程中可作为影响屠宰性能的候选基因。为了提高鹌鹑的屠宰性能,本试验选择145只鹌鹑作为试验材料,通过非探针高分辨率熔解曲线(HRM)的方法对其进行FATP1和TBC1D1基因分型,并与屠宰性状(活重、屠体重、腿肌重、胸肌重、全净膛重、半净膛重、胸肌率、腿肌率)进行关联分析。结果表明:FATP1基因有一个多态位点存在AA、AG、GG 3种基因型,AA基因型鹌鹑的活重、屠体重、半净膛重、全净膛重、腿肌重和胸肌重显著高于AG、GG基因型(P0.05),且AA基因型鹌鹑的屠宰性能均明显高于其他两种类型的鹌鹑;AG、GG基因型间差异不显著(P0.05),AA基因型鹌鹑的胸肌率高于AG基因型和GG基因型,GG基因型腿肌率高于AA基因型和AG基因型,但差异均不显著(P0.05)。TBC1D1基因在变异位点处存在TT、TG和GG 3种基因型,TT基因型鹌鹑的半净膛重、全净膛重和胸肌重均显著高于TG基因型(P0.05);TT基因型鹌鹑的活重、屠体重、半净膛重、全净膛重、腿肌重和胸肌重均显著高于GG基因型(P0.05),TT基因型鹌鹑的腿肌率、胸肌率均高于TG基因型和GG基因型,但差异不显著(P0.05)。说明AA、TT基因型有可能是影响朝鲜鹌鹑屠宰性状的主效基因型,在选种中可作为辅助选择的分子标记。     

鸡PIK3C2A基因第6内含子多态性及其与体尺和屠体性状的关联分析

本研究采用直接测序法检测了无量山乌骨鸡磷脂酰肌醇-4-磷酸3-激酶催化亚基2型α(PIK3C2A)基因内含子的单核苷酸多态性(SNPs),并分析其与体尺和屠体性状的关联性。研究发现,在鸡PIK3C2A基因内含子上共检测到5个SNPs。关联分析表明,g.38511TA位点与龙骨长和胫围相关(P0.05),g.38573CT位点与盆骨宽和胫围相关(P0.05),g.38632TC和g.38662AG位点与胸角和胫围相关(P0.05),g.38729CT位点与胸角和盆骨宽相关(P0.05或P0.01);g.38511TA位点与屠体率相关(P0.05),g.38632TC位点与活重、屠体重、半净膛重、全净膛重、腹脂重和腹脂率相关(P0.05或P0.01),g.38662AG和g.38729CT位点与活重、屠体重、半净膛重、全净膛重和胸肌率相关(P0.05或P0.01)。本研究结果表明,PIK3C2A基因的5个SNPs位点与无量山乌骨鸡的体尺和屠体性状相关(P0.01),可作为鸡体尺和屠体性状的分子标记辅助选种。     

京海黄鸡MC4R基因多态性及其与部分屠体性状的关联分析

以140只京海黄鸡个体为研究对象,采用PCR-SSCP和克隆测序技术分析了鸡MC4R基因的多态性。结果表明:MC4R基因第662位发生G→C突变,第733~734位间插入1个C碱基;χ2检验结果表明,实验中发现的多态位点均处于Hardy-Weinberg不平衡状态;GLM分析结果显示,AB型个体腿肌重极显著高于BB型(P0.01),DD型个体胴体重和半净膛重显著高于CD型(P0.05),AA/DD组合型个体具有高于其他基因型的趋势。因此推测,MC4R基因可以作为影响和控制鸡屠体性状的候选基因。     

拜城油鸡肌肉生长抑制素基因多态性与生产性能的相关性研究

试验旨在研究肌肉生长抑制素（myostatin,MSTN）基因在拜城油鸡中的多态性及其与生产性能的关系,探寻可用于拜城油鸡选育的分子遗传标记。选取96只6周龄的拜城油鸡公鸡,随机分为3组,每组32只,分别在12、18和24周龄时对其生产性能指标进行测定,同时采用PCR-RFLP方法检测MSTN基因的多态性,分析MSTN基因多态性与拜城油鸡生产性能的关系。结果显示,在拜城油鸡公鸡中MSTN基因存在多态性,检测到3种基因型:AA、GA、GG,GA为优势基因型,等位基因A为优势等位基因,不符合哈代－温伯格平衡定律（P<0.05）。在12周龄时,AA基因型个体的体重、屠体重、半净膛重、全净膛重、胸肌重和腿肌重均显著高于GA基因型个体（P<0.05）;在18周龄时,GA基因型个体的体重、胸肌重和腿肌重均显著高于GG基因型个体（P<0.05）;在24周龄时,AA基因型个体的体重、屠体重和半净膛重均极显著高于GG基因型个体（P<0.01）,全净膛重和腿肌重显著高于GG基因型个体（P<0.05）,GA基因型个体的体重、屠体重、半净膛重和腿肌重均显著高于GG基因型个体（P<0.05）,其余指标在不同周龄不同基因型个体间差异不显著（P>0.05）。MSTN基因多态性与拜城油鸡部分生产性能指标密切相关,推测该基因可以作为拜城油鸡选育的分子遗传标记之一。     

荆江麻鸭GH基因第4外显子SNP及其与体性状的关联研究

采用PCR-SSCP方法检测了96只荆江麻鸭生长激素基因第4外显子序列多态性,并分析了基因多态性与屠体性状间的关系.结果发现,在荆江麻鸭生长激素基因第4外显子中检测到1个突变位点,为3701 nt处C→T碱基转换,产生AA、BB和AB3种基因型,其中野生基因型BB为优势基因型(54.17%).卡方检验结果表明,群体该位点处于遗传平衡状态(P＞0.05).最小二乘分析结果表明,AA基因型个体全净膛率显著高于BB基因型(P＜0.05).初步推断,GH基因可作为影响荆江麻鸭部分屠体性状的候选基因(标记),其中突变基因型AA为有利基因型.     

边鸡MSTN基因C.234位点对生长性状的遗传效应分析

采用PCR-RFLP技术检测连续2个世代边鸡群体肌肉生长抑制素基因外显子1的多态性,分析了多态位点对边鸡生长性状的遗传效应。结果表明,边鸡MSTN基因的C.234位点存在多态性,在外显子1编码区的234bp处发生G→A的碱基突变,产生了GG、GA和AA 3种基因型。关联分析表明,无论是一世代还是二世代的边鸡群体,在6~16周龄时,AA和GA基因型边鸡的体质量均显著或极显著的高于GG基因型（P〈0.05或P〈0.01）。结果提示,MSTN基因外显子1的C.234位点突变对边鸡的生长性状具有显著的遗传效应,初步推断该位点可用于边鸡生长性状的标记辅助选择。     

7个品种鸭MSTN基因5’-调控区单核苷酸多态性研究

为了研究肌肉生长抑制素(MSTN)基因在鸭群体中的遗传变异情况,试验以莆田黑鸭、连城白鸭、绍兴鸭、攸县麻鸭、建昌鸭、高邮鸭及北京鸭为材料,采用连接酶检测反应(LDR)的方法对MSTN基因5’-调控区第1 024位点单核苷酸多态性(SNP)进行基因分析,并统计该位点在群体中的基因型频率、等位基因频率和Hardy-Weinberg平衡情况。结果表明:在7个品种鸭中,检测MSTN基因第1 024位点均含CC、CG和GG 3种基因型。在连城白鸭、攸县麻鸭和高邮鸭中,CC基因型占优势,且以连城白鸭最高(0.72);在高邮鸭和建昌鸭中,CG基因型占优势;在北京鸭中,GG基因型占优势;在绍兴鸭中,CC基因型、CG基因型出现的频率相同。建昌鸭和北京鸭等位基因G的频率高于等位基因C的频率,其他品种鸭均为等位基因C的频率大于等位基因G的频率。莆田黑鸭、连城白鸭、绍兴鸭、攸县麻鸭、北京鸭和高邮鸭MSTN基因在第1 024位点均处于Hardy-Weinberg平衡状态(P>0.05),仅有建昌鸭不符合Hardy-Weinberg平衡状态(P<0.05)。     

肌细胞生成素基因多态性与泸宁鸡生长性状的关联研究

本研究旨在探讨肌细胞生成素(myogenin,MyoG)基因多态性与泸宁鸡生长性状的关联性.采用PCR-SSCP和DNA测序技术,对泸宁鸡MyoG基因5'调控区的多态性进行检测.结果表明,泸宁鸡MyoG基因5'调控区存在4个多态位点(A153G、A267G、A446G和C612T).在153 bp处存在A/G突变,形成3种基因型(AA、AG和GG),其中AA基因型肝脏重显著高于AG、GG基因型(P <0.05).在446 bp处存在的A/G突变,形成3种基因型(AA、AG和GG),该位点GG基因型屠宰率显著高于AA、AG基因型(P <0.05),AG、GG基因型胸肌率显著高于AA基因型(P <0.05).以上结果显示,MyoG基因5'调控区的多态性与泸宁鸡肝脏重、屠宰率、胸肌率有一定的关联性,可作为泸宁鸡相应生长性状的候选基因.     

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 1983

In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.

Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.

     

Heartworm in dogs in Canada in 1991

In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium.     

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 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 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 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%).     

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.