利用微卫星标记分析五个家兔群体的遗传多样性

利用15个微卫星座位,分析了新西兰白兔、德系安哥拉兔、美系獭兔、齐卡G系肉兔、福建黄兔5个家兔群体的遗传多样性。结果表明：15个微卫星位点的平均等位基因数和平均有效等位基因数分别为7．400±1．639个和5．694±1．470个;5个家兔群体的平均基因杂合度和平均多态信息含量分别为0．7367和0．6994;新西兰白的平均基因杂合度和平均多态信息含量最高,福建黄兔最低。5个家兔群体的平均总近交系数（F_is）为-0．03,群体内平均近交系数（F_is）为-0．151,群体平均分化系数（F_is）为0．105（P〈0．001）。采用UPGMA法进行聚类分析,5个家兔群体聚为三类：新西兰白兔和德系安哥拉兔聚为一类;齐卡兔G系和美系獭兔聚为一类,福建黄兔独自为一类。     

新西兰白兔、福建黄兔遗传多样性分析

利用经筛选多态性较好的18对微卫星引物,对新西兰白兔、福建黄兔进行遗传多样性检测。研究结果表明,2个兔品种在18个微卫星座位上的基因频率存在一定的差异;新西兰白兔群体的基因杂合度和多态信息含量分别为0.593和0.533;福建黄兔群体的基因杂合度和多态信息含量分别为0.613和0.560。福建黄兔群体基因平均杂合度和平均多态信息含量较新西兰白兔高;说明福建黄兔的遗传多样性较新西兰白兔丰富。     

长江三角洲白山羊群体遗传结构研究

应用结构基因座和微卫星DNA两种遗传标记探讨长江三角洲白山羊群体遗传结构。结果表明,检测的9个结构基因座位上7个存在多态性,座位的基因平均杂合度、多态信息含量及有效等位基因数分别为0.1767、0.1457和1.2837;7个微卫星位点上共检测到110个等位基因,位点的基因平均杂合度、多态信息含量及有效等位基因数分别为0.8867、0.8774和11.2907。群体内的遗传变异程度相对较高,反映出丰富的遗传多样性,而且微卫星DNA标记揭示的遗传变异高于结构基因座。     

略阳乌鸡黑羽和白羽群体微卫星遗传多态性分析

为了对略阳乌鸡黑羽和白羽两个群体遗传多态性进行评估,研究从FAO推荐使用的30对微卫星标记中筛选出8个有效标记进行遗传分析。结果显示:8个微卫星位点在略阳乌鸡中共检测到41个等位基因,黑羽乌鸡和白羽乌鸡两个群体的等位基因数基本一致,但不同群体存在各自的优势等位基因和特有等位基因。略阳黑羽乌鸡8个位点的平均观察杂合度、平均期望杂合度、Nei′s期望杂合度和平均多态信息含量分别为1.0、0.789 5、0.750 0和0.663 1;白羽乌鸡8个位点的平均观察杂合度、平均期望杂合度、Nei′s期望杂合度和平均多态信息含量分别为0.839 3、0.728 2、0.702 2和0.651 4。研究结果表明,略阳黑羽乌鸡和白羽乌鸡群体内均保存着较为丰富的遗传多样性,种群内不存在近交问题,该品种在选育和生产中没有导入外血,品种纯正,保留了较为原始的基因库。     

家兔群体遗传变异的微卫星标记

选用欧洲野生穴兔的5个微卫星座位,分析了5个品种(系)家兔群体的遗传变异.结果表明:Vc-Ⅱ系獭兔的群体内平均多态信息含量和平均杂合度均最大,分别为0.552 6和0.620 2;新西兰兔群体内平均多态信息含量和平均杂合度都最小,分别为0.451 5和0.526 1,说明在5个品种(系)家兔中,新西兰兔群体内变异较小,相对较纯;Vc-Ⅱ系獭兔群体内变异较大,纯度相对较小.但总的来看,5个品种(系)家兔的平均多态信息含量和平均杂合度相差都不大,说明Vc獭兔在遗传性能上已接近其他优良品种兔.聚类结果表明:Vc-Ⅰ系獭兔与Vc-Ⅱ系獭兔亲缘关系最近,与日本大耳兔、青紫蓝兔亲缘关系较近,与新西兰兔亲缘关系最远,这与Vc獭兔育种事实相符.在Sat4和Sat8座位分别检测出了一条Vc獭兔所特有的条带,从而为进一步研究Vc獭兔的遗传特性打下良好的基础.     

长江三角洲白山羊群体遗传结构研究

应用结构基因座和微卫星DNA两种遗传标记探讨长江三角洲白山羊群体遗传结构。结果表明,检测的9个结构基因座位上7个存在多态性,座位的基因平均杂合度、多态信息含量及有效等位基因数分别为0．1767、0．1457和1．2837;7个微卫星位点上共检测到110个等位基因,位点的基因平均杂合度、多态信息含量及有效等位基因数分别为0．8867、0．8774和11．2907。群体内的遗传变异程度相对较高,反映出丰富的遗传多样性,而且微卫星DNA标记揭示的遗传变异高于结构基因座。     

家兔群体遗传变异的微卫星标记

选用欧洲野兔的 5个微卫星位点 ,分析了 5个品种 (系 )家兔群体的遗传变异。结果表明 :Vc- 系獭兔的群体内平均多态信息含量和平均杂合度最大 ,分别为 0 .5 5 2 6和 0 .6 2 0 2 ;新西兰兔群体内平均多态信息含量和平均杂合度最小 ,分别为 0 .4 5 15和 0 .5 2 6 1。由此说明 ,5个品种 (系 )家兔中 ,新西兰兔群体内变异较小 ,相对较纯 ;Vc- 系獭兔群体内变异较大 ,纯度相对较小。但总的来看 ,5个品种 (系 )家兔的平均多态信息含量和平均杂合度相差都不大 ,说明Vc獭兔在遗传性能上已接近其他优良品种兔。聚类结果表明 :Vc- 系獭兔与 Vc- 系獭兔亲缘关系最近 ,与日本大耳白兔、青紫蓝兔亲缘关系较近 ,与新西兰兔亲缘关系最远 ,这与 Vc獭兔育种历史事实相符。另外 ,在 Sat4和 Sat8位点上分别检测出了 1条 Vc獭兔所特有的条带 ,从而为进一步研究 Vc獭兔的遗传特性打下良好的基础     

盘羊及其杂交后代微卫星遗传多样性分析

为了更好地了解盘羊及其杂交后代（盘羊♂×欧拉羊♀）的遗传信息,为盘羊遗传资源评价及欧拉羊的复壮改良提供理论依据。本试验选取24对微卫星引物,应用PCR扩增和毛细管电泳的方法对24只盘羊和24只杂交羊个体进行遗传多样性分析。结果显示,在24只盘羊中,24个微卫星位点上共检测到167个等位基因,平均等位基因数目为6.9583,平均有效等位基因数为3.3665,平均观测杂合度为0.4497,平均期望杂合度为0.6779,平均多态信息含量为0.6265,其中,等位基因数目最多的是位点MAF70,有效等位基因数目、期望杂合度、多态信息含量最高的是位点OarFCB193,观测杂合度最高的是位点ILSTS11;在24只杂交羊中,24个微卫星位点上共检测到154个等位基因,平均等位基因数目为6.4166,平均有效等位基因数为3.4061,平均观测杂合度为0.4566,平均期望杂合度为0.6751,平均多态信息含量为0.6265,其中,等位基因数目、有效等位基因数目、期望杂合度、多态信息含量最高的是位点MAF70,观测杂合度最高的是位点OarJMP58。从遗传学角度得出,盘羊和杂交羊遗传指标结果相近,试验所得数据可用于盘羊遗传资源评价及欧拉羊的复壮改良。     

运用微卫星标记对中国地方绵羊品种的遗传多样性分析

利用30对微卫星引物,以中国西部7个地方绵羊（Ovi saries）品种为研究对象,通过计算基因频率、平均杂合度（H）、多态信息含量（PIC）及有效等位基因数目（Ne）,并根据共祖遗传距离矩阵进行UPGMA聚类分析,评估其品种内和品种间的遗传变异。结果表明：在30个座位中,共检测到239个等位基因,平均每个座位等位基因数为8个;品种平均有效等位基因数为2.9～3.4个,座位平均有效等位基因数为1.9～5.3个;座位平均杂合度为0.320～0.818,品种平均杂合度在0.656～0.719之间,座位平均PIC为0.388～0.786,品种平均PIC在0.590～0.666之间。聚类分析表明各绵羊品种聚类结果与其来源、育成史和地理分布基本一致,其中有争议之处仍待进一步探讨。     

岷县黑裘皮羊微卫星遗传多样性分析

试验旨在分析岷县黑裘皮羊群体内遗传多样性,筛选出理想的遗传标记,为岷县黑裘皮羊的选育保种提供理论依据。选取144只岷县黑裘皮羊,颈静脉采血并提取DNA,对24对微卫星引物进行PCR扩增,用毛细管电泳技术进行基因分型,计算其等位基因数、等位基因大小及频率、有效等位基因数、杂合度和多态信息含量。结果显示,24个位点共检测到210个等位基因,平均等位基因数为8.75;群体等位基因频率为0.0104~0.7396,等位基因片段大小为97~285 bp;有效等位基因数为1.7581~8.2433个;群体平均观测杂合度为0.4839;平均期望杂合度为0.6959;平均多态信息含量为0.6527。其中MAF70位点等位基因数、有效等位基因数、期望杂合度和多态信息含量最高;OarFCB128位点观测杂合度最高;OarAE129位点等位基因数最少,SRCRSP9位点期望杂合度、多态信息含量最低;OarFCB304位点观测杂合度最低。Hardy-Weinberg平衡分析结果表明,所选位点中有19个处于非平衡状态。结果表明,岷县黑裘皮羊的遗传背景复杂,群体内遗传多样性丰富,可为其遗传资源的评估和选育保种工作提供理论依据。     

4个家兔品种MHC-DQA基因外显子2 Mbo Ⅱ酶切多态性分析

采用PCR-RFLP方法对4个不同品种家兔MHC-DQA基因外显子2的遗传多态性进行检测,并进行聚类分析。结果表明,在家兔MHC-DQA基因外显子2的第103 bp处表现出多态性;χ²适合性检验结果表明,Mbo Ⅱ酶切位点在齐卡大型新西兰白兔和齐卡巨型白兔群体均没有达到Hardy-Weinberg平衡状态(P＜0.05),而在齐兴肉兔和加利福尼亚兔群体均达到Hardy-Weinberg平衡状态(P＞0.05);聚类分析结果表明,齐卡大型新西兰白兔与齐卡巨型白兔亲缘关系最近。试验结果为进一步利用MHC进行抗病育种提供了分子生物学基础。     

Comparison of ear canal microbiome in rabbits with and without otitis externa using next generation DNA sequencing

BackgroundContemporary research has increasingly explored the clinical applicability of next-generation DNA sequencing (NGS) technologies in veterinary medicine, which has provided new and practical opportunities for rabbit otitis externa clinical interventions. The objectives of this study were to characterize the normal external ear canal microbiome of clinically healthy rabbits compared to otitis externa presenting rabbits, and to assess the diagnostic viability of NGS in aural veterinary medicine.MethodsSwabs from the external ear canal of 34 clinically healthy rabbits and 16 rabbits diagnosed with otitis externa were collected. Alongside bioinformatic analysis, library preparation was performed targeting the V1-V3 region of the 16S rRNA bacterial gene and the ITS-2 region for fungal DNA analysis.ResultsIn the clinically healthy group, the bacterial species with the highest relative abundances were an uncharacterized Phytoplasma from the family Acholeplasmataceae (8.74%) and Staphylococcus epidermidis (5.56%), while in the otitis group the species with the highest relative abundances were Staphylococcus aureus (12.59%), Corynebacterium lactis (9.27%), and Corynebacterium mastitidis (7.92%). Fungal species with the highest relative abundances in the healthy group were a species from the genus Cladosporium (14.46%), while in the otitis externa group the fungal species with the highest relative abundances were a species from the genus Cladosporium (9.89%) and Malassezia restricta (4.76%). Additionally, there was a significantly higher number of different bacterial and fungal species in the clinically healthy group compared to the otitis group (P = 0.00 and P = 0.00, respectively).Conclusions and clinical relevanceThis study provided evidence that the rabbit aural microbiome profile is distinctly different between a clinically healthy and an otitis state. It also highlighted new bacterial and fungal organisms of note in rabbits diagnosed with otitis externa compared to those previously thought to be the primary disease-causing organisms. Understanding the microbial population dynamics in the rabbit aural microbiome is particularly critical for helping clinicians recognize, prevent, or revert the progression of otitis.     

闽西南黑兔与新西兰白兔的屠宰性能及肉品质研究

本实验旨在研究闽西南黑兔及新西兰白兔的屠宰性能及肉品质,为闽西南黑兔在异地(山东省)繁育提供理论基础。选择35日龄、断奶体重(854±13)g的闽西南黑兔及断奶体重(635±18)g的新西兰白兔各20只(公、母各半),饲养管理相同,在(100±2)d全部进行屠宰,测定屠宰性能和肉品质指标。结果表明:闽西南黑兔的屠宰体重、胴体重等显著低于新西兰白兔;闽西南黑兔的背最长肌的红度值和黄度值显著高于新西兰白兔,肌肉脂肪沉积显著低于新西兰白兔;新西兰白兔的背最长肌中n-6多不饱和脂肪酸显著高于闽西南黑兔,各屠宰性能和肉品质之间没有显著的性别差异。本研究表明,相比新西兰白兔,闽西南黑兔的肌肉呈现良好的色泽,不饱和脂肪酸沉积少。     

A serial cross-sectional study of the prevalence of rabbit haemorrhagic disease on three farms in the lower North Island of New Zealand

AIM: To estimate over a 3-year period following the first release of rabbit haemorrhagic disease virus (RHDV) the prevalence of rabbit haemorrhagic disease (RHD) and the abundance of rabbits (Oryctolagus cuniculus) in an area that historically had low rabbit densities.

METHODS: Three farms grazing predominantly sheep and beef cattle, located close together and with low initial rabbit densities, were selected for study. RHDV had been deliberately released on all farms in December 1997. Farms were visited 2–3 times per year between June 1998 and April 2001. At each visit, rabbits were shot with the aid of spotlights at night and blood samples were collected for detection of RHDV antibodies. Rabbit carcasses were necropsied and the age of the animals was determined. Rabbit abundance on each property was measured throughout the study using spotlight night counts. Logistic regression was used to identify factors associated with the risk of carcasses being seropositive for RHDV.

RESULTS: Rabbit density differed initially between farms (8.2, 9.9, 2.3 rabbits per spotlight km in June 1998), and declined on all three properties over time (1.2, 2.4, 1.1 rabbits per spotlight km in November 2000). Highest antibody titres to RHDV were initially evident on the farm on which rabbits were most abundant. The average prevalence of seropositive rabbits overall was 21% (95% CI=15–28%). Female rabbits tended to be less likely to be seropositive for RHDV than males (OR=0.47; 95% CI=0.21–1.02). The odds of becoming seropositive were reduced for rabbits born in the breeding season of 1999–2000 (OR=0.17; 95% CI=0.05–0.64).

CONCLUSIONS: The temporal pattern of outbreaks measured by peaks of seroprevalence differed between closely-spaced farms when they had different rabbit densities, but were similar when rabbit densities were similar. Microclimate and vegetation influencing abundance of insect vectors for RHDV and intrinsic population-related factors like rabbit breeding behaviour are also likely to be involved in local patterns of spread.     

Conjunctival flora observed in 70 healthy domestic rabbits (Oryctolagus cuniculus)

Conjunctival swabs were taken from both eyes of 70 healthy domestic rabbits and cultured to determine the microbial population. Bacteria were recovered from 83 per cent of the specimens. DNase-negative Staphylococcus species (57 per cent) were the most commonly recovered organisms followed by Micrococcus species (25 per cent) and Bacillus species (19 per cent). Other organisms isolated included Stomatococcus species (8 per cent), Neisseria species (8 per cent), Pasteurella species (6 per cent), Corynebacterium species (6 per cent), Streptococcus species (6 per cent) and Moraxella species (4 per cent), and other bacteria were isolated less frequently. Statistical analysis showed that there appeared to be no significant difference between the bacterial isolation rates from different breeds of rabbit. Significantly more of the swabs taken from young rabbits yielded cultivable bacteria than did those taken from rabbits over 12 months of age.     

Six cases of inguinal urinary bladder herniation in entire male domestic rabbits

Six entire male rabbits, between four and eight years old, were presented with a fluctuant scrotal and/or inguinal swelling resulting from inguinal herniation of the urinary bladder. Concurrent problems included urinary sediment (two rabbits), multiple uroliths (one rabbit) and testicular tumour (one rabbit). All rabbits underwent herniorrhaphy surgery. There was a successful outcome in four of the six cases.     

A serial cross-sectional study of the prevalence of rabbit haemorrhagic disease on three farms in the lower North Island of New Zealand

AIM: To estimate over a 3-year period following the first release of rabbit haemorrhagic disease virus (RHDV) the prevalence of rabbit haemorrhagic disease (RHD) and the abundance of rabbits (Oryctolagus cuniculus) in an area that historically had low rabbit densities. METHODS: Three farms grazing predominantly sheep and beef cattle, located close together and with low initial rabbit densities, were selected for study. RHDV had been deliberately released on all farms in December 1997. Farms were visited 2-3 times per year between June 1998 and April 2001. At each visit, rabbits were shot with the aid of spotlights at night and blood samples were collected for detection of RHDV antibodies. Rabbit carcasses were necropsied and the age of the animals was determined. Rabbit abundance on each property was measured throughout the study using spotlight night counts. Logistic regression was used to identify factors associated with the risk of carcasses being seropositive for RHDV. RESULTS: Rabbit density differed initially between farms (8.2, 9.9, 2.3 rabbits per spotlight km in June 1998), and declined on all three properties over time (1.2, 2.4, 1.1 rabbits per spotlight km in November 2000). Highest antibody titres to RHDV were initially evident on the farm on which rabbits were most abundant. The average prevalence of seropositive rabbits overall was 21% (95% CI=15-28%). Female rabbits tended to be less likely to be seropositive for RHDV than males (OR=0.47; 95% CI=0.21-1.02). The odds of becoming seropositive were reduced for rabbits born in the breeding season of 1999-2000 (OR=0.17; 95% CI=0.05-0.64). CONCLUSIONS: The temporal pattern of outbreaks measured by peaks of seroprevalence differed between closely-spaced farms when they had different rabbit densities, but were similar when rabbit densities were similar. Microclimate and vegetation influencing abundance of insect vectors for RHDV and intrinsic population-related factors like rabbit breeding behaviour are also likely to be involved in local patterns of spread.     

不同水平柚叶饲粮对生长肉兔血清生化指标、消化和免疫功能的影响

本试验旨在研究不同水平柚叶饲粮对生长肉兔生理机能的影响,进一步评估柚叶作为家兔饲料原料的可行性。选取120只遗传背景相同、健康的35日龄法国伊拉商品兔,适应7 d后,按体重[(1 179.25±53.74)g]相近原则随机分为4组,每组10个重复,每个重复(笼)3只。对照组饲喂不含柚叶的基础饲粮,试验组分别饲喂含6%(Ⅰ组)、12%(Ⅱ组)和18%(Ⅲ组)柚叶的试验饲粮,4种饲粮的能、氮和纤维含量基本相等。试验期28 d。结果发现:1)除Ⅲ组血清球蛋白含量显著高于对照组和Ⅱ组(P0.05),Ⅱ组血清球蛋白含量显著低于Ⅰ组(P0.05)以及Ⅲ组白球比显著低于Ⅱ组(P0.05)外,其余血清生化指标各组间无显著差异(P0.05)。2)饲粮中添加柚叶对生长肉兔消化器官发育指标无显著影响(P0.05)。除试验组后期丙酸比例及Ⅲ组中期盲肠内容物p H和氨态氮浓度显著低于对照组(P0.05)以及Ⅱ组中期p H显著高于Ⅲ组(P0.05)外,其余盲肠发酵参数各组间差异不显著(P0.05)。3)除Ⅲ组血清免疫球蛋白A水平显著低于对照组和Ⅰ组(P0.05)以及Ⅰ组血清免疫球蛋白A水平显著高于对照组和Ⅱ组(P0.05)外,其余免疫指标各组间均无显著差异(P0.05)。由此得出,生长肉兔自由采食含6%~18%柚叶的饲粮4周,不明显负面影响血清生化指标、消化及免疫功能,进一步提示柚叶可作为家兔的饲料原料使用。     

家兔HSL基因多态性及其与生产性状关联性分析

本实验采用PCR-SSCP方法对齐卡巨型白兔和齐兴肉兔HSL基因外显子1的遗传多态性进行研究,并进一步分析HSL基因对生产性状的遗传效应。结果表明:HSL基因外显子1第784位处发生了碱基突变(A→C),共出现AA、AB和BB 3种基因型,在2个品种兔群体中AA型均为优势基因型,A均为优势等位基因;卡方适合性检验表明,2个品种兔群体均显著偏离哈代-温伯格平衡(P0.05);在齐卡巨型白兔中,HSL基因AA型和AB型个体的宰前活体重均显著高于BB型个体(P0.05),AA、BB型个体的全净膛屠宰率和半净膛屠宰率均显著低于AB型个体(P0.05);在齐兴肉兔中,HSL基因AA型个体的宰前活体重显著高于AB、BB型个体(P0.05),BB型个体的全净膛屠宰率和半净膛屠宰率均显著低于AA、AB型个体(P0.05);在2个品种兔群体中,不同基因型个体的滴水损失和剪切力差异均不显著(P0.05)。