温岭高峰牛的染色体研究

用C带、G带、RBA带、核仁组织者区银染色和常规+RBA带连续染色技术研究了我国南方的9头温岭高峰公牛、2头母牛和1头温岭(♀)利本赞(♂)的杂种公牛的染色体。温岭牛2n=60,公牛xy,母牛xx,x为一大的亚中着丝点杂色体,Y为小的近端着丝点染色体。杂种公牛的Y为小的亚中着丝点染色体。温岭牛的Ag—NORs除定位于2、3、4、11、28号染色体上之外,在21号染色体上也有银染颗粒,但出现频率很低。21号和28号染色体末端Ag—NOR出现频率分别为每细胞0.11个和1.79个。温岭牛中存在2/27罗伯逊易位。     

晋南黄牛的染色体分析

以晋南黄牛为实验材料,做了染色体的常规分析。测量了各号染色体的相对长度、着丝点指数及臂比,并做了染色体的C带、R带及银染核仁组织者区(Ag-NORs)的分析。染色体常规染色及C带、R带分析表明:晋南黄牛公牛的核型为2n=60,XY。Y染色体有两种形态,一为近端着丝点染色体,另一为中着丝点染色体。Ag-NORs定位于第2、8、4、11、21(或22)及28号常染色体的末端,银染频率为每细胞6.109。讨论了另一品种双核型现象。认为晋南黄牛是我国北方普通牛与南方肩峰牛两大牛群汇合的交汇点之一。     

蒙古牛和延边牛的染色体研究

做了4头蒙古牛(♂)和12头延边牛(11♂,1(?))的染色体研究。做了两种牛的常规染色、C带和核仁组织者区银染色的核型和蒙古牛的G带核型分析。蒙古牛的Y染色体为亚中着丝点,而延边牛为中着丝点,存在形态上的差别,但他们的大小均位于24—25号常染色体之间。蒙古牛和延边牛的Ag—NORs均定位于2.3.4.11.28号常染色体末端,但发现延边牛的Ag—NORs也定位于21(或22)号染色体末端。根据两种牛的Y染色体和Ag—NORs多态性讨论了它们的起源问题。     

峨边花牛的染色体分析

四川省峨边花牛核型为2n=60,公牛为X、Y,母牛为XX,Y染色体为近端着丝粒染色体,根据其核型特征,峨边花牛应为瘤牛后裔.用C带和R带可以容易地鉴别峨边花牛的Y染色体.     

四川黄牛的分类地位与染色体G带核型研究

为了进一步研究四川黄牛的遗传特性及分类地位,本文以瘤牛(印度辛地红牛,我国海南牛)和普通牛(西门塔尔牛、成都黑白花牛)为对照,采用GTG技术进行四川黄牛G带核型研究。结果表明,四川黄牛G带核型与瘤牛相似,与普通牛不同。主要表现在Y染色体的形态和结构顺序上,四川黄牛和瘤牛Y=AG带带型:近端区至少2条暗带,远端为较宽明带,末端为狭窄暗带。普通牛Y=SM,长臂至少2条暗带、短臂为较宽明带,末端狭窄暗带,短臂G带分布与前两种牛长臂远端一致,可能是臂间倒位的结果。G带研究支持前文认为四川黄牛分类应属Bos indicus的研究结果。     

云南小耳猪核型分析

本文采用外周血淋巴细胞短期培养方法,以及G—带、C—带技术,对云南小耳猪染色体进行了核型分析。其结果表明小耳猪二倍体细胞染色体数为20=38。雄性为18对常染色体和1对性染色体XY;雌性为18对常染色体和1对性染色体XX。根据染色体测量结果,将所有常染色体分为四组:A组,1—5对,为近中着丝点染色体;B组、6—7对、为近端着丝点染色体;C组,8—12对,为中着丝点染色体;D组,13—18对,为端着丝点染色体。性染色体X为中着丝点染色体,Y为最小的近中着丝点染色体。G—带分析表明,每一对同源染色体都有其特殊的染色体带型。C—带分析揭示,1号和13—18号染色体的着丝点区域皆为深染,而Y染色体的着丝点区和整个长臂深染尤为明显,其余各对染色体的C—带染色则随着不同细胞而有所不同。     

秦川牛CEBPA基因遗传变异对体尺和胴体性状的影响

试验以CCAAT增强子结合蛋白A(CEBPA)为候选基因,采用直接测序的方法寻找秦川牛CEBPA基因SNP,筛查到一个新的多态位点T963G,该突变位于基因的编码区。运用PCR-RFLP方法验证并分析该位点在215头秦川牛群体中的多态性。结果表明:在秦川牛群体中分布A、B 2个等位基因,处于中度多态。经过χ2适合性检验,秦川牛群体在该位点达到Hardy-Weinberg平衡状态(P0.05)。将该T963G位点的基因型与体尺、胴体性状进行关联分析,表明该位点与胴体重显著相关(P0.05),BB为有利基因型,B等位基因为有利等位基因,提示该位点有可能作为秦川牛胴体性状标记辅助选择的标记之一。     

四川黄牛的研究

本研究对四川黄牛、黑白花奶牛、西门达尔牛、雷琼牛、辛地红牛进行了细胞遗传和生化遗传的研究,结果表明:四川黄牛在遗传基础上[柴色体的一般核型、G—带核型、C—核型、Ag—NOR的频率分布与定位、血液蛋白(Tf、Tb)基因种类及频率分布]与瘤牛(Bos indicus)基本一致,而和普通牛(Bos taurus)有明显的差异。在外形上具有瘤牛的三种峰型及发达的垂皮和体格特征,在生物学特性方面具有瘤牛的耐热、耐粗饲、抗湿、抗蜱等特点,根据上述细胞遗传、生化遗传的证据,结合形态学、生物学特征的研究,根据进化细胞学观点,哺乳动物核型进化理论及生化遗传在分类中的应用原理表明:四川黄牛应属瘤牛种。同时对四川黄牛的发生演化作了初步探讨。     

中国四个地方黄牛品种的染色体研究(论文详细摘要)

采用外周血淋巴细胞培养法,以 G-,C-分带和银染技术,对我国4个地方黄牛品种延安地区蒙古牛(10 ♂;5♀)、关中秦川牛(12♂;4),商洛山阳的岭南牛(6♂;5♀)以及陕南西乡的西镇牛(9♂;12)共计63头黄牛的染色体核型,G 带和C 带以及 Ag—NoRs 数目和分布进行了详细的研究。结果发现,性染色体(x 和 y)和     

东北民猪的染色体组型及分带研究

本文采用外周血淋巴细胞短期培养方法,骨髓细胞染色体直接制片技术,以及G—分带、C—分带和银染技术,对东北民猪的染色体组型、G—分带带型以及结构性异染色质的分布.18S+28S rDNA的定位和数目进行了分析。结果表明,东北民猪二倍体细胞染色体数为2n=38。雄性为18对常染色体和1对性染色体XY;雌性为18对常染色体和1对性染色体XX。根据染色体测量结果,将所有常染色体分为四组:A组1—5对,为近中着丝点染色体;B组6—7对,为近端着丝点染色体;C组8—12对,为中着丝点染色体;D组13—18对,为端着丝点染色体。性染色体X为中着丝点染色体,其大小介于8号与9号染色体之间。Y为最小的中着丝点染色体。东北民猪染色体的G—分带带型与国内外其它品种的G—分带带型基本一致。经胰酶—Giemsa分带处理后,同一染色体在不同的长度可以显示出不同数目的G—带;染色体越长,所显带的数目就越多。C—分带分析揭示,东北民猪染色体的着丝点区均有结构性异染色质的分布,其中1—4号,13—18号染色体的着丝点区显著的深染,13—18号染色体的着丝点区,结构性异染色质分布范围大并呈现多态现象。几乎整个Y染色体都有结构性异染色质的分布。银染分析揭示,18S+28S rDNA定位于8号和10号染色体的次缢痕处,每个细胞18S+28S rDN A的分布范围为1—3     

C- AND G- BANDING PATTERNS AND CHROMOSOMAL MORPHOLOGY OF SOME BREEDS OF AUSTRALIAN CATTLE

A cytogenetical study using metaphase chromosomes from cultured lymphocytes, was made of 2 Banteng (Bibos banteng) steers and 218 bulls representing 13 purebreeds (Bos taurus type, Bos indicus type and Sanga) and 7 cross-breeds. Studies were made of photographic karyotypes of Giemsa stained and C-banded chromosomes of bulls of each breed and of B-banded chromosomes from 3 breeds of Bos indicus and one cross-breed Australian Friesian Sahiwal) cattle. The relative lengths of chromosomes of Bos taurus and Bos indicus bulls were compared and significant difference in relative lengths of the X chromosomes were noted between these two species. There was a differences in morphology of the Y chromosomes; Sanga, Banteng and Bos taurus type breeds had a small submetacentric Y chromosome, except for the Jersey which had a metacentric Y chromosome. All Bos indicus type bulls had an acrocentric Y chromosome but the Droughtmaster breed had two forms of the Y chromosome (submetacentric and acrocentric). The C-banding patterns of the autosomes and X chromosomes were similar for all breeds while those of the Y chromosomes of Bos indicus type cattle allowed their accurate identification. G-banding patterns of Bos indicus resembled those of Bos taurus and enabled pairing of homologous chromosomes. Centromeres of the autosomes were unstained but those of the sex chromosomes were darkly stained.     

Y CHROMOSOME MORPHOLOGY OF CATTLE

Metaphase chromosomes from cultured lymphocytes were prepared from 246 bulls including Bos indicus, Bos taurus. Bos (Bibos) banteng, Sanga and interspecific and intra-specific breed crosses. Morphology and karyotype position of the Y chromosome for each bull were noted. Karyotype position of the Y chromosome varied between bulls from 25th to 29th pair and the Y chromosomes of Bos indicus and breeds derived from Bos indicus bulls were acrocentric while those of Bos taurus, Sanga and breeds derived from these bulls were metacentric/submetacentric. Two forms of Y chromosome were noted in the Droughtmaster breed. C-banding patterns of the acrocentric Y chromosome were characteristic and enabled easy identification.     

秦川牛Y染色体多态性与精液品质,体尺及外貌特征关系的探讨

在秦川牛品种中，Ｙ染色体具有多态性，即中或亚中及近端着丝点Ｙ染色体。对不同类型Ｙ染色体公牛的精液品质，体尺及外貌特征进行了统计分析。结果表明，Ｙ染色体多态性与精液品质，体尺及外貌特征不存在一定的相关关系。并对其意义和原因进行了讨论。     

Karyotypes of three shrew species (Soriculus nigrescens,Episoriculus caudatus and Episoriculus sacratus) from Nepal

The karyotypes of three shrew species (Mammalia, Soricomorpha, Soricidae) from Nepal were examined for the first time. Based on the karyotypes and overall differences in skull size, the current Episoriculus caudatus appeared to include two distinct species: the larger E. caudatus and the smaller Episoriculus sacratus. Episoriculus sacratus has three subspecies, E. s. soluensis in Nepal and Sikkim, E. s. umbrinus in Assam, Myanmar and the Yunnan Province of China, and E. s. sacratus in the Sichuan Province of China. Soriculus nigrescens had a diploid chromosome number (2n) and fundamental number (FN), including two X chromosomes, of 64 and 92, respectively, consisting of 11 metacentric or submetacentric, two subtelocentric and 18 acrocentric pairs of autosomes, a metacentric X and an acrocentric Y chromosome. Episoriculus sacratus soluensis had 2n = 74 and FN = 126, consisting of 12 metacentric or submetacentric, 13 subtelocentric and 11 acrocentric pairs of autosomes, a submetacentric X and an acrocentric Y chromosome. Episoriculus caudatus had 2n = 60 and FN = 118, consisting of 19 metacentric or submetacentric, nine subtelocentric and one acrocentric pair of autosomes, a subtelocentric X and an acrocentric Y chromosome. The karyotypes of these three species are characterized by their large 2n and FN values compared with other Soricidae.     

哈白兔×日本大耳兔F1的染色体核型分析

采用常规细胞遗传学手段,对青海省畜牧兽医科学院饲养的哈白兔×日本大耳兔Ｆ１的染色体核型进行分析,结果表明,Ｆ１的染色体数目２ｎ＝４４,染色体臂数ＮＦ＝７８（♂）;常染色体类型１～７对为中着丝粒染色体（Ｍ）,８～１０对为亚中着丝粒染色体（ＳＭ）,１１～１６对为近端着丝粒染色体（ＳＴ）,１７～２１对为端着丝粒染色体（Ｔ）,性染色体Ｘ为亚中着丝粒染色体（ＳＭ）,Ｙ为中着丝粒染色体（Ｍ）,公兔核型式为４４,ＸＹ（♂）。     

Chromosomes of gaur cross domestic cattle hybrids

The chromosomes of five gaur (Bos gaurus hubbacki) domestic cattle (B indicus cross B taurus) hybrids (three females, two males) were studied using the leucocyte culture method and centromeric (C) banding technique. All the hybrids had a diploid chromosome number of 2n = 58, made up of two submetacentric autosomes (different in size) and 54 acrocentric autosomes, most of which could be arranged in pairs in descending order of size. The sex (X) chromosomes in females were a pair of submetacentric chromosomes smaller than the submetacentric autosomes. The Y chromosome in males was a small submetacentric chromosome. The C banding patterns were useful in identifying the X and Y chromosomes and the inherited submetacentric autosomes from the gaur sire. Phenotypically, the hybrids resembled normal B indicus cross B taurus calves except for the presence of a distinct hump-like dorsal ridge containing the spinous processes of the third to 11th thoracic vertebrae, upright 'deer-like' ears and long lean legs. The potential of these hybrids as important genetic resources for meat production is stressed.     

A note on the somatic Y chromosome of reindeer (Rangifer tarandus L.)

Recently a report on the reindeer chromosomes was published (Nes et al. 1965). The chromosome complement was described as consisting of 70 autosomes and a sex chromosome set of the XY-type. All autosomes were acrocentric except one pair which was submetacentric. The X was found to be submetacentric and also the largest chromosome of the complement. The Y was characterized as being the smallest acrocentric chromosome, and the authors stated that the Y chromosome could only occasionally be distinguished from the autosomes by its shorter length.In our studies of the same species we have found a quite different appearance concerning the Y chromosome.     

荒漠猫染色体的首次研究

采用外周血淋巴细胞培养和常规染色体制备分析技术，对青海省珍稀兽类荒漠猫染色体进行首次研究，结果显示：荒漠猫的染色体数目为２ｎ＝３８，常染色体形态类型为１０Ｍ＋１０ｓＭ＋１２ｓＴ＋４Ｔ（或Ａ），性染色体形态类型Ｘ为ｓＭ，Ｙ为ｓＴ，染色体总臂数ＮＦ＝７２，公母猫核型式为３８，ＸＹ和３８，ＸＸ。     

西藏黄牛染色体的研究

研究了西藏黄牛的普通核型和Ｃ带核型，着重分析了Ｙ染色体的形态。结果表明，西藏黄牛核型为２Ｎ＝６０，公牛为ＸＹ，母牛为ＸＸ，常染色体为近端着丝粒染色体。Ｘ染色体为亚中着丝粒染色体，Ｙ染色体中中部着丝粒杂色体。根据Ｙ染色体的形态讨论了西藏黄牛的起源。     

马鹿染色体核型分析

采用常规细胞遗传学分析手段，对青海省西宁动物园饲养的马鹿染色体核型进行分析，结果：马鹿染色体数目为２ｎ＝６８，染色体臂数ＮＦ＝７０（♀）、７１（）；常染色体类型为２条中（Ｍ）着丝粒，６４条近端或端（Ａ）着丝粒；性染色体类型Ｘ为近端（Ａ），Ｙ为近中（ｓＭ）着丝粒；公母鹿核型式为６８，ＸＹ和６８ＸＸ。