调节耗牛繁殖时间提高犊牛成活率的可行性探讨

牦牛的繁殖性能受日照、气温、营养等环境因素的影响。依据牦牛研究已取得的成果特别是母牦牛发情、排卵规律、性周期激素水平特性作为应用基础研究成果,结合国内外先进的动物繁殖新技术,建立调节牦牛繁殖时间,提高犊牛成活率的技术方案,人为的控制母牦牛发情,调节繁殖时间,将母牦牛的发情时间推迟1-2个周期,调整、控制在水草丰茂的7月中旬至9月初集中发情、配种,把产犊时间调节在气候较为暖和、牧草返青的4-5月集中产犊,达到提高受胎率、繁殖成活率是完全可行的。     

诱导牦牛同期发情试验

应用生殖激素处理诱导牦牛同期发情 ,结果表明 :LRH -A3 +PMSG和PG -CL +FSH处理的试验母牦牛 96h以内的发情率分别达 83 3 3 %和 73 3 3 %,极显著地高于未处理的对照牛(2 0 0 0 %) (P <0 0 1 ) ,两试验组之间差异不显著 (P >0 0 5 ) ;不同繁殖类型母牦牛外周血浆P4和 1 7β -E2 含量的测定结果 :牙日玛母牦牛外周血浆P4 和 1 7β -E2 的含量略高于青麻和干巴母牦牛 (P >0 0 5 )。     

牦牛繁殖科学研究进展

主要分析总结了近五年来牦牛繁殖科学在生殖内分泌调节机制、诱导发情与同期发情、超数排卵、牦牛及牦牛与普通牛体外受精、牦牛与普通牛异种体细胞核移植等方面的研究进展和存在的问题,并提出了如何将这些研究进展应用到牦牛生产中以提高牦牛业的经济效益以及进一步开展牦牛繁殖科学研究的思路.     

牦牛同期发情试验效果初报

牦牛是青藏高原的特有畜种。由于长期受分布地区社会经济,自然条件的作用,牦牛仍处于生产性能较低的原始品种状态。母牦牛一般3—4岁开始配种,每年集中在7—9月发情,其营养好坏,对发情与否的影响很大。据调查,1979年全省牦牛的繁活率为40.7％,(皇城公社1979年牦牛的繁活率为51％,)多数产犊母牦牛当年不发情,一般母牦牛为二年一产,繁殖率较低。     

州科研院畜科所“牦牛同期发情技术研究”项目取得重大突破

由阿坝州科技局立项支持的"牦牛同期发情技术研究"项目,于2004年和2005年共同期处理全奶母牦牛76头,经人工授精加自然交配,妊娠68头,受胎率为89.47%;其中:人工授精受胎率为18.42%,自然交配受胎率为71.05%。通过牦牛同期发情研究及技术示范,达到快速扩大牦牛种间杂交改良群     

牦牛发情周期血浆中LH、P_4、17β-E_2的变化规律及其与卵巢功能的关系

选择13头5—7岁的健康母牦牛做试验牛,用成年阉牦牛做试情牛,结合直肠检查卵泡发育情况。从发情之日起,每天一次(发情期每天两次)用真空采血管从颈静脉采血2.0ml,离心分离血浆。血浆用液氮滴冻成颗粒,保存于液氮罐中。血浆LH、P4、17β-E_2含量用放射免疫分析法测定。结果表明,牦牛发情周期血浆P4水平在发情期较低,平均0.1785±0.0928ng/ml;黄体期较高,平均5.1824±0.3475ng/ml。17β-E_2在发情盛期上升到峰值,平均27.2918±2.1057Pg/ml,发情结束后降至基础水平,黄体期,在第4和9天时分别出现一峰值,到第16天时又上升到发情盛期水平。LH在发情初期较低,友情盛期上升到峰值,平均17 1824±2 1174ng/ml,发情结束后降至基础水平,黄体期在1～3ng/ml间波动。本文根据牦牛发情周期血浆LH、P4、17β-E_2的变化特点,结合直肠检查结果,探讨了牦牛发情周期血浆LH、P4、17β-E_2的变化规律及其与卵巢功能的关系。认为:母牦牛的发情应以静立接受试情牛爬跨为指征,牦牛的排卵发生在LH峰后约24小时内,即在母牦牛静立接受试情牛爬跨后24小时内。     

阿尔泰山牦牛的种间杂种

阿尔泰山具有低矮植被的辽阔草原,普通牛、绵羊和山羊难以利用、而牦牛及其种间杂种能很好的利用。牦牛对饲料要求不严和不需建筑畜舍的投资,终年放牧在草场,被毛能极好地防寒。牦牛的繁殖力和普通牛一样,先进牧工由100头母牦牛可获得100头犊牛。牦牛是群居的家畜,一名牧工可放牧200—300头。牦牛成熟晚,7岁才能生长结束,成年母牦牛活重     

影响牦牛繁殖力的因素

牦牛是高原特有品种 ,而影响牦牛繁殖力的因素有遗传、环境、营养、配种时间、管理等 ,所以进行影响牦牛繁殖力各种因素的系统研究 ,直接制约着当地畜牧业的可持续发展     

母犬阴道角化上皮细胞与最适交配期的研究

实验用阴道涂片法检测经激素处理的空怀8个月、1年以上母犬,产后45、60、90天诱导发情以及自然发情母犬阴道角化上皮细胞的变化,作为确定母犬最适交配时间的依据.结果表明,激素处理后第13—17天,空怀母犬阴道角化上皮细胞比例迅速增高,达到81%后7—10天接受交配;产后45、60和90天的母犬经激素处理诱导发情后,分别于处理的第22、17和24天达到80%角化上皮细胞,此后2—4天接受交配.自然发情大、小型母犬发情出血后第8天达到80%角化上皮细胞,持续2—4天后接受交配.自然发情的大、小型母犬,发情出血后第10—11天, 角化上皮细胞比例均超过80%.试验结论:可依阴道涂片法确定母犬发情最适交配期的检测指标之一用于生产实践     

母犬阴道角化上皮细胞与最适交配期的研究

实验用阴道涂片法检测经激素处理的空怀８个月和１年以上母犬，产后４５天、６０天、９０天诱导发情以及自然发情母大阴道角化细胞的变化，作为确定母犬最适交配时间的依据。结果表明：可依阴道涂片法确定母犬发情最适交配期，并以此作为检测指标之一用于生产实践．     

大鼠APKD基因分子克隆研究(Ⅱ)大鼠基因组文库中APKD基因同源顺序的克隆——筛选与鉴定

以人ＡＰＫＤ基因探针２１８Ｅｐ６在大鼠基因组文库中筛选到阳性克隆ｐＭ１,经充分鉴定证实含有探针的同源顺序     

Genome sequence and analysis of the tuber crop potato

Potato (Solanum tuberosum L.) is the world's most important non-grain food crop and is central to global food security. It is clonally propagated, highly heterozygous, autotetraploid, and suffers acute inbreeding depression. Here we use a homozygous doubled-monoploid potato clone to sequence and assemble 86% of the 844-megabase genome. We predict 39,031 protein-coding genes and present evidence for at least two genome duplication events indicative of a palaeopolyploid origin. As the first genome sequence of an asterid, the potato genome reveals 2,642 genes specific to this large angiosperm clade. We also sequenced a heterozygous diploid clone and show that gene presence/absence variants and other potentially deleterious mutations occur frequently and are a likely cause of inbreeding depression. Gene family expansion, tissue-specific expression and recruitment of genes to new pathways contributed to the evolution of tuber development. The potato genome sequence provides a platform for genetic improvement of this vital crop.     

人类基因组计划及研究

近年来,采用ＤＮＡ序列测定、基因克隆、基因组文库的构建等方法对人类基因组进行了研究,完成了大部分人类基因组的物理图谱、转录图谱及单核苷酸多态性图谱的分析。进而发现、克隆和研究了许多新基因,如青光眼基因、肿瘤抑制基因等,这些结果使人类第一次在分子水平上认识自我,并有助于从人灰基因组中去除有害基因。最后本文探讨了人类基因组研究可能带来的问题。     

采用基于GSS序列的极大节旋藻(Arthrospira maxima)的基因克隆策略及其应用实例

电子克隆是随着基因组计划的实施而发展起来的利用生物信息学手段进行基因克隆的新方法,已经公布的极大节旋藻GSS序列使得电子克隆极大节旋藻的功能基因成为可能.为建立极大节旋藻功能基因的高效克隆策略,应建立利用GSS序列克隆极大节旋藻功能基因的基本策略并加以应用.具体操作方法：对dbGSS数据库中的605条极大节旋藻GSS序列进行拼接及功能注释,并在分析编码区完整性的基础上设计引物并进行PCR扩增以获得基因全长序列,利用以上策略成功克隆了极大节旋藻功能基因ureaseβ和dUTPase的全长序列.     

Functional annotation of a full-length mouse cDNA collection

The RIKEN Mouse Gene Encyclopaedia Project, a systematic approach to determining the full coding potential of the mouse genome, involves collection and sequencing of full-length complementary DNAs and physical mapping of the corresponding genes to the mouse genome. We organized an international functional annotation meeting (FANTOM) to annotate the first 21,076 cDNAs to be analysed in this project. Here we describe the first RIKEN clone collection, which is one of the largest described for any organism. Analysis of these cDNAs extends known gene families and identifies new ones.     

A physical map of the mouse genome

A physical map of a genome is an essential guide for navigation, allowing the location of any gene or other landmark in the chromosomal DNA. We have constructed a physical map of the mouse genome that contains 296 contigs of overlapping bacterial clones and 16,992 unique markers. The mouse contigs were aligned to the human genome sequence on the basis of 51,486 homology matches, thus enabling use of the conserved synteny (correspondence between chromosome blocks) of the two genomes to accelerate construction of the mouse map. The map provides a framework for assembly of whole-genome shotgun sequence data, and a tile path of clones for generation of the reference sequence. Definition of the human-mouse alignment at this level of resolution enables identification of a mouse clone that corresponds to almost any position in the human genome. The human sequence may be used to facilitate construction of other mammalian genome maps using the same strategy.     

SMART法构建蚕豆全植株cDNA文库

采用了一种简单而快速的全长cDNA文库构建法,即SMART法,并应用cDNA片段与质粒共转化大肠杆菌的方法,成功地构建了蚕豆全植株cDNA文库.     

Primary structure and genomic organization of the histidine-rich protein of the malaria parasite Plasmodium lophurae

The nucleotide sequence of a complete genomic clone for the histidine-rich protein of Plasmodium lophurae has been determined. The deduced amino acid sequence of the mature protein shows numerous tandemly repeated units preceded by a signal and a pro peptide. The gene is interrupted by an intron with a separate exon coding for the signal peptide. The signal peptide-encoding exon detects multiple cross-hybridizing sequences in the parasite genome.     

Genome sequence and comparative analysis of the model rodent malaria parasite Plasmodium yoelii yoelii

Species of malaria parasite that infect rodents have long been used as models for malaria disease research. Here we report the whole-genome shotgun sequence of one species, Plasmodium yoelii yoelii, and comparative studies with the genome of the human malaria parasite Plasmodium falciparum clone 3D7. A synteny map of 2,212 P. y. yoelii contiguous DNA sequences (contigs) aligned to 14 P. falciparum chromosomes reveals marked conservation of gene synteny within the body of each chromosome. Of about 5,300 P. falciparum genes, more than 3,300 P. y. yoelii orthologues of predominantly metabolic function were identified. Over 800 copies of a variant antigen gene located in subtelomeric regions were found. This is the first genome sequence of a model eukaryotic parasite, and it provides insight into the use of such systems in the modelling of Plasmodium biology and disease.