地方、培育、引入品种资源的保存与发展的研究进展

作者就20世纪 80年代以来我国多次畜禽资源调查的结果作了详细的介绍,报道了576个品种在近30年来的变迁情况。除了常见的马、驴、黄牛、水牛、大额牛、牦牛、绵羊、山羊、猪、鸡、鸭、鹅、特禽的品种以外,尚有7种,如骆驼、兔、梅花鹿、马鹿、水貂、貉、蜂等动物。其中地方品种426个,培育品种73个,引入品种77个。已有19个地方品种灭绝,37个受严重威胁。作者回顾了20世纪末开始应用遗传检测手段,包括个体、细胞、蛋白质和分子水平4个层次的研究进展。证明多层次综合研究才能反映品种的全貌。建议资源调查中要着重选育强度带来的影响,品种调查提纲必须周密,要以品种特征和外貌为主,与遗传分析相结合,才可能提出可行的保种和开发方案。作者论证了配子和胚胎超低温保存、DNA保存的前景,并指出与企业合作进行保种的动向,国家应长期重点加以支持。     

家畜基因组遗传多态标记—微卫星标记研究进展(下)

３微卫星标记的应用自微卫星被发现以来就受到了家畜遗传育种家们的高度重视,并且充分认识到了把它作为畜种的基因组变异研究所具有的巨大的潜在价值。现在它已被十分成功地作为富含信息、又容易获得的基因标记,广泛用于构建物种的遗传连锁图,基因鉴定（基因诊断）、物...     

贵州地方猪品种毛色与KIT基因拷贝数之间的关联分析

为了研究KIT基因的拷贝数与贵州地方猪毛色之间的关系,本试验以黔北黑猪、柯乐猪、糯谷猪、香猪4个地方品种为试验材料,采用实时荧光定量PCR方法检测基因组中KIT基因的拷贝数变异,并与荣昌猪和大白猪2个白毛色猪品种相比较.结果显示,4个贵州地方猪种中,全黑/全棕毛色个体的KIT基因拷贝数以缺失为主,黑色带白斑个体的KIT基因拷贝数全部缺失,而棕色带白个体的KIT基因拷贝数增加、正常各半.大白猪的KIT基因拷贝数显著增加,荣昌猪KIT基因拷贝数以正常类型为主.表明大白猪的白毛色由KIT基因拷贝数增加决定,但荣昌猪的白毛色可能与KIT基因的拷贝数变异之间没有直接的联系;4个贵州地方品猪的全黑/全棕色毛色与KIT基因拷贝数的缺失有关,但柯乐猪和香猪中带白斑个体的KIT基因拷贝数并未增加,提示贵州地方猪品种的白斑毛色的形成机制有一定的特殊性.     

中国地方绵羊品种的地域分布及肉用相关性状的多元分析

【目的】中国畜禽遗传资源种类丰富,畜禽品种数量约占全球已知种类的1/6,是世界畜禽遗传资源最为丰富的国家之一。《中国畜禽遗传资源志》是在农业部的领导和组织下,经过8年的调查和编写而成,较好的总结了中国畜禽地方品种、培育品种和引入品种地域分布和性能特点。文章对《中国畜禽遗传资源志-羊志》中地方绵羊品种的重要生产性能相关性状作进一步分析,期望从中筛选出适合于肉用品种培育的素材。【方法】整理汇总《羊志》中地方绵羊品种的主要产地,以及体尺、胴体及繁殖方面共13个肉用相关性状信息。依据《羊志》将地方品种分为蒙古系、哈萨克系和藏系并对3大谱系进行多重比较,利用R语言中主成分分析和系统聚类分析方法对信息较全的地方绵羊品种进行聚类分析。【结果】从地理分布图可以看出中国绵羊地方品种分布广泛,以新疆、云南、内蒙古和山东4个省（自治区）品种数量最多,分别为13、7、5和5个。从地形分布来看中国地方绵羊品种主要集中在北部、西北部以及西南部高原地区。从绵羊谱系分布来看,哈萨克系品种主要集中在新疆地区,藏系品种主要分布于云贵高原,蒙古系则是品种种类最多分布最广的一支,在中国北部、中原地区及东部均有饲养;3大谱系的多重比较分析结果表明,蒙古系生产性能最好,藏系最差,哈萨克系居中;主成分分析表明通过结合前两个主成分1和2能将3大谱系区分开,可以推断出《羊志》中未明确谱系的地方品种,如大尾寒羊和广灵大尾羊为蒙古系,岷县黑裘皮羊为藏系;随后系统聚类分析又将地方绵羊品种划分3个类别并对肉用相关性状进行多重比较,根据每个类别的肉用相关性状特点分别命名为低产低繁组、高产低繁组和高产高繁组。其中高产高繁组包括7个地方品种,分别为小尾寒羊、多浪羊、大尾寒羊、洼地绵羊、太行裘皮羊、豫西脂尾羊和湖羊。【结论】挑选的绵羊相关表型信息可以用来辨别并推断未知谱系绵羊品种的谱系,未来可应用于新发现绵羊品种资源的分类。在42个地方绵羊品种中发现7个品种的生产性能接近于专门化肉用绵羊品种标准,是肉用绵羊培育或配套系杂交利用的理想材料。研究不仅是对中国地方绵羊遗传资源的再认识,也为研究《中国畜禽遗传资源志》的其他畜禽品种资源研究提供参考。     

中国6个地方鸭品种蛋品质比较

本研究测定了处于产蛋高峰6个地方鸭品种同一天各30枚种蛋的蛋重、壳重、蛋黄重、蛋白重、膜重、蛋黄蛋白比、哈氏单位、蛋壳厚度、蛋黄色泽、蛋形指数、蛋壳强度等11项蛋品质的指标。结果表明:高邮鸭除哈氏单位稍低外,其他10项指标均比其他5个鸭品种高;11项指标主成分分析说明了蛋重是蛋品质的一个重要指标,6个鸭品种分别依特征值排序的结果中,由前到后顺序为:高邮鸭、金定鸭、莆田黑鸭、山麻鸭、攸县麻鸭、连城白鸭。研究结果为进一步开发利用品种资源提供了参考依据。     

An international panorama of goat selection and breeds

The preservation of the biodiversity of animal breeds is an important condition to maintain the ability of animal production to adapt to the changing conditions of breeding and production systems in the future. The decrease of the number of animal breeds has been observed both for sheep, cattle and goats in relation with the standardisation and intensification of animal production systems.Goats are mainly concerned by the situation as they have the biggest increase in livestock numbers in 20 years. A global overlook of goats worldwide is showing a contradictory situation: On one hand, small but well organised sectors have developed in a few countries for milk and cheese, meat and fibre production. On the other hand, most of the goats are mostly still used for auto consumption of milk meat and skin or fibres in village herds. The present goat genetic situation is the direct consequence of this evolution with the high specialisation of a small number of selected and well characterised breeds for milk, meat and fibres and a majority of not well defined populations and local breeds, generally without selection schemes and organisation.A global panorama of the main families and breeds is presented. A special consideration is then pointed on the necessary financial and logistic conditions to achieve successively these selection objectives. After having observed that in many cases these conditions are not present, this report concludes by some proposals to control better the possibilities of success and express with more efficiency the genetic potentiality of this interesting species.     

Evaluation of estimated genetic merit for carcass weight in beef cattle: Blood metabolites, carcass measurements, carcass composition and selected non-carcass components

In Ireland, a new beef genetic index has been developed. Growth rate is expressed as expected progeny difference for carcass weight (EPD_CWT) and is estimated on an across-breed basis. Cross-breeding of dairy cows with both Aberdeen Angus and Belgian Blue beef sires is widely practised. The objective of this study was to compare blood metabolites, slaughter traits and carcass composition of progeny from Holstein–Friesian dairy cows and Aberdeen Angus (AA), Belgian Blue (BB), Friesian (FR) and Holstein (HO) sires. The AA and BB sires were selected, within breed, to be of either high (H) or low (L) estimated genetic merit for carcass weight. A total of 170 male progeny from spring-calving cows and 42 sires (10 AA, 13 BB, 7 FR and 12 HO) were artificially reared indoors and managed together until the end of their second grazing season when they were assigned to either a Light (560 kg) or Heavy (620 kg) slaughter weight. Blood metabolite concentrations were measured six times throughout life and feed intake was recorded during the first and second winter. Carcass measurements and selected non-carcass components were recorded after slaughter and the right side of each carcass was dissected into lean, fat and bone. Differences in blood metabolite concentrations amongst genetic groups were negligible although there were some effects of the prevailing level of nutrition. M. longissimus area scaled for carcass weight was 0.220, 0.221, 0.260, 0.255, 0.212 and 0.208 (SE 0.004) cm²/kg for AAH, AAL, BBH, BBL, FR and HO, respectively. Carcass measurements scaled for carcass weight were greater for L, AA, HO and the dairy strains than for H, BB, FR and the beef breeds, respectively. There was no effect of estimated genetic merit for carcass weight on carcass composition. Statistically significant interactions between genetic merit and beef breed existed for some traits with the genetic merit effect largely evident for AA only. BB and the beef breeds had more lean, less fat and more high value lean in the carcass than AA and the dairy strains, respectively. It is concluded that genetic group had little effect on blood metabolite concentrations but there were some feeding level effects. Estimated genetic merit for carcass weight affected carcass weight, m. longissimus area and carcass measurements scaled for carcass weight but the effects were confined to AA. There were large effects of beef breed and dairy strain on carcass composition.     

5个地方鸡种肌肉脂肪酸相对含量比较及主成分分析

以5个地方鸡品种(白耳鸡、狼山鸡、萧山鸡、北京油鸡、泰和乌骨鸡)为研究对象,比较13项肌肉脂肪酸组成指标的相对含量在品种间的差异,并对13项脂肪酸组成指标进行因子分析和系统聚类分析.结果表明:泰和乌骨鸡和狼山鸡的饱和脂肪酸相对含量最高(分别为44.96%和43.26%),均与白耳鸡的饱和脂肪酸相对含量之间存在显著差异(P<0.05).白耳鸡的不饱和脂肪酸相对含量最高(63.99%),与泰和乌骨鸡、狼山鸡的不饱和脂肪酸相对含量之间存在显著差异(P<0.05).白耳鸡的必需脂肪酸相对含量最高(6.76%),且与狼山鸡(3.84%)、泰和乌骨鸡(4.17%)相对含量间存在显著差异(P<0.05),但与萧山鸡(5.98%)、北京油鸡相对含量(6.72%)之间差异不显著(P>0.05).主成分分析获得的前3个主成分可以解释全部变异的94.865%,其中第1、2、3主成分分别解释总变异的58.632%、22.479%和13.754%.基于主成分值的UPGMA聚类图和3-D聚类图,将5个地方鸡种聚为3大类,萧山鸡、狼山鸡和北京油鸡聚为一类,白耳鸡、泰和乌骨鸡分别形成独立分支.     

我国家禽产业化育种及制种的研究

探索家禽良种的社会经济的地位、属性、发展历史和现状。提出21世纪家禽育种、制种的发展方向和方法,建议采用生态优选育种方案与双选育种法及核心群选育法培养优质家禽良种,同时用生物技术进行辅助选择。用科学发展观构建我国家禽育种制种基地。     

应用微卫星标记分析云南、西藏4个地方特色鸡种的遗传多样性

利用18对微卫星引物测定云南省、西藏自治区4个地方特色鸡种(‘藏鸡’、‘勐腊茶花鸡'、‘贡山土鸡'、‘武定鸡’)的遗传多样性,对等位基因频率、等位基因数、有效等位基因数、群体杂合度和多态信息含量等遗传多样性参数进行了统计分析,并依据Nei氏DA遗传距离,采用NJ法和UPGMA法构建了系统聚类树.结果表明:18个微卫星座...