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利用位于绵羊不同染色体的9个微卫星标记对新疆紫泥泉国家二级种羊场中国美利奴(新疆军垦型)A品系、B品系绵羊基因组DNA的遗传多样性进行了检测。统计了中国美利奴(新疆军垦型)A品系、B品系绵羊在9个位点的平均杂合度(H)、有效等位基因数(E)、9个微卫星位点的等位基因频率多态信息含量(PIC)和位点平物多态信息含量(PIC)以及中国美利奴(新疆军垦型)A品系、B品系绵羊基因座频率的抽样估计等遗传指标。研究表明:9个微卫星位点在中国美利奴(新疆军垦型)A品系、B品系中均存在遗传多态性,其中5个与产毛性状相关的位点可作为区分A、B品系的依据(5个位点为BM6438、ILSTS004、BM143、BM6516、BM1824);通过分析各品系的遗传结构和特性,如等位基因频率等,对中国美利奴绵羊的选育提高有帮助。 相似文献
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苏丹草主要性状遗传的初步研究 总被引：2，自引：0，他引：2
以不同来源的６个苏丹草品系为材料，研究了与产草量有关的８个性状的基本遗传参数、性状间相关和遗传参数、性状相关和遗传通径分析。结果表明，遗传变异系数以叶宽最大，抽穗期最小；单株干重的遗传力最低，抽穗期的遗传力最高；株高和叶宽的遗传也很高，与株得的正向遗传系数达显著水平，对株重的直接和间接效应最大。因此，株高和叶宽既是田间直接选择的主要性状，又是对株高进行间接选择的主要性状。 相似文献
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扁蓿豆不同品系ISSR标记遗传差异和遗传多样性 总被引：4，自引：1，他引：3
采用ISSR分子标记技术对扁蓿豆4个品系的遗传多样性、遗传差异和遗传结构进行了研究。用7个有效引物对4个品系进行PCR扩增,共获得73个等位基因位点,每条引物平均检测出10.4个位点,其中多态性位点69个,多态位点百分率为94.5%。各品系的Nei’s遗传多样性为0.2569,Shannon’s信息指数为0.4046。Nei’s指数估算和分子方差分析均表明,扁蓿豆4个品系的遗传多样性主要存在于品系内,4个品系间亦出现了较大的遗传分化(Gst=0.1324)。品系00-61、90-36、00-81和93-21的多态位点百分率分别为73.97%、79.45%、82.19%和83.56%;Nei’s遗传多样性(H)分别为0.2050、0.2153、0.2264和0.2474;Shannon’s信息指数(I)分别为0.3222、0.3396、0.3538和0.3821。各品系的遗传参数大小排序均为品系93-21品系00-81品系90-36品系00-61。采用系统聚类和主坐标分析(PCA)两种方法所获得的聚类结果一致,即品系00-61和00-81遗传差异相对较小,其次是品系90-36,品系93-21与各品系的遗传差异较大。 相似文献
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应用单引物PCR指纹技术分析Vc-獭兔的分子遗传结构 总被引：2，自引：0，他引：2
采用1条小卫星引物M13(5’GAGGGTGGCGGTTCT3’)和2条微卫星引物(GTG)5、(GACA)4，对Vc—Ⅰ系、Vc—Ⅱ系獭兔、日本大耳白兔(JWR)和青紫蓝(QZL)4个品系各8只，总计32个个体的遗传结构进行了DNA指纹分析。结果，3条引物的扩增产物都呈现良好的多态性和稳定性；对每个品系混合DNA池进行分析，计算出了4个品系间及32个个体间的共有带率及遗传距离指数，通过聚类分析，得出各品系间和个体间欧式遗传距离，并绘制出4个品系间及各品系32个个体问的亲缘关系树状聚类图，从而初步建立了4个品系兔的SPAR指纹图谱。 相似文献
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本文讨论了性状间遗传相关的遗传机制和育种应用问题,认为造成性状间遗传相关的主要原因有时可能是基因连锁有进可能是一因多效,但一般可是二者共存,互有强弱。不管哪 种原因为主,高度遗传相关的性状总是可以认为受同一连锁群的基因所控制,所以育种实践中用性状间遗传相关的平方为指标对全部目标性状进行聚类分析,同类性状属同一连锁群,所以就做为同一品系的目标性状而不宜放在不同品系中分别选育,且连锁群多少可做为品种内 相似文献
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金定鸭3个品系间的杂交效果分析 总被引：2，自引：0，他引：2
金定鸭３个品系间的杂交效果分析赖垣忠，陈奕欣，陈小麟，吕良炬，潘丽娉（福建厦门大学生物学系３６１００５）纵观现代国际家禽业，就家食品种而言，几乎都采用商品配套品系。虽然，品系的育成方法不尽一致，但都是在现代遗传育种理论指导下，获得加性和非加性遗传效应... 相似文献
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分析了3个纯系商品肉鸡MHC和非-MHC位点的遗传多态性。用Southern杂交技术检测MHC-Ⅰ型和Ⅳ型位点，并判定RFLP的基因型。在这些肉鸡品系中，检测到4种MHC一Ⅱ型和8种Ⅳ型基因型，它们的基因频率不同。检测了各个品系的特异性MHC基因型。杂合度(59％～67％)显示这些品系的MHC位点具有高度的多态性，MHC位点至少9％的遗传变异是由品系差异引起的。为了检测非-MHC基因，对这3个品系肉鸡非MHC基因组上41微卫生位点进行研究，结果发现它们的微卫星位点存在遗传变异；每个位点等位基因数范围为1～8个。每个品系的平均等位基因数分别为3．5、2．8、3．1。座位的杂合度范围为0％～89％。通过对固定指数(Fst)的分析，发现该基因微卫星座位的遗传差异19％是品系间差异造成的。对MHC和非-MHC座位进行Hardr-Weinberg平衡定律检验，结果2个位点处于连锁不平衡。这可能是由遗传选择或非等位基因存在造成的。本研究主要阐明了商品代肉鸡的群体分子遗传特性和遗传结构。MHC和非-MHC位点的研究结果表明：肉种品系仍具有丰富的遗传多样性，可为继续提高肉鸡的生产性能提供有用的基因资源。 相似文献
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三个鸡品系的遗传差异与杂种优势关系的研究 总被引：1，自引：0，他引：1
采用RAPD标记分析了武定鸡快羽系、绿壳蛋系和合成系间的遗传差异,进行了三个鸡品系间的杂交试验,并应用简单的线性相关分析了遗传距离指数与杂种优势的关系。分析结果表明快羽系与绿壳蛋系间的遗传差异较小,而快羽系与合成系间的遗传差异较大。品系间遗传距离指数与F1代各性状观察值均为正相关,但相关不显著;与杂种优势率之间也均为正相关,但只与13周龄存活率、种蛋受精率有显著的相关关系。表明RAPD标记在预测杂种优势上具有一定参考价值。 相似文献
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Response of white leghorn chickens of various genetic lines to infection with avian leukosis virus subgroup J 总被引：2，自引：0，他引：2
In Experiment 1, chickens from various white leghorn experimental lines were inoculated with strain ADOL-Hcl of subgroup J avian leukosis virus (ALV-J) either as embryos or at 1 day of age. At various ages, chickens were tested for ALV-J induced viremia, antibody, and packed cell volume (PCV). Also, at 4 and 10 wk of age, bursal tissues were examined for avian leukosis virus (ALV)-induced preneoplastic lesions with the methyl green-pyronine (MGP) stain. In Experiment 2, chickens harboring or lacking endogenous virus 21 (EV21) were inoculated with strain ADOL-Hcl of ALV-J at hatch. All embryo-inoculated chickens in Experiment 1 tested positive for ALV-J and lacked antibody throughout the experimental period of 30 wk and were considered viremic tolerant, regardless of line of chickens. By 10 wk of age, the incidence of ALV-J viremia in chickens inoculated with virus at hatch varied from 0 (line 0 chickens) to 97% (line 1515); no influence of ALV-J infection was noted on PCV. Results from microscopic examination of MGP-stained bursal tissues indicate that ALV-J can induce typical ALV-induced transformation in bursal follicles of white leghorn chickens. Lymphoid leukosis and hemangiomas were the most common ALV-J-induced tumors noted in chickens in Experiment 1. At termination of Experiment 2 (31 wk of age), 54% of chickens harboring EV21 were viremic tolerant compared with 5% of chickens lacking EV21 after inoculation with ALV-J at hatch. The data indicate that genetic differences among lines of white leghorn chickens, including the presence or absence of EV21, can influence response of chickens to infection with ALV-J. 相似文献
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Gizzard lesions were formed in specific-pathogen-free (SPF) white leghorn chickens inoculated with fowl adenovirus (FAV). The virus, serotype 1 FAV 99ZH strain (FAV-99ZH), was originally isolated from the gizzard mucosa of commercial broiler chickens exhibiting gizzard erosion with intranuclear inclusion bodies. Five-day-old and 53-day-old SPF white leghorn chickens were inoculated with FAV-99ZH by both oral and ocular routes and then examined at necropsy on days 3, 5, 7, 10, 14, and 21 postinoculation (PI). There were no clinical signs in any of the chickens after the inoculation. Focal gizzard lesions occurred macroscopically, however, in inoculated chickens at several experimental periods. FAV was recovered from tissue samples of the proventriculus, gizzard, pancreas, and rectum by day 10 or 7 PI but was not recovered from liver samples of any of the chickens. These results indicate that FAV isolated from gizzard erosion is able to reproduce gizzard lesions as necrosis and erosion in SPF white leghorn chickens and that it may have a greater degree of tissue tropism in gizzards and other digestive organs than in the liver. 相似文献
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Thirty-eight 7-week-old white leghorn chickens of two strains (high and low antibody response to sheep erythrocytes) were divided into groups for exposure to high and low levels of social stress. They were then challenged orally with a toxic dose of the organophosphate insecticide malathion (250 mg/kg body weight) and evaluated 60 min later for muscarinic signs (diarrhea, lacrimation, respiratory secretions), nicotinic signs (muscle weakness), plasma cholinesterase activity, and brain acetylcholinesterase activity. A significant correlation was shown between clinical and biochemical indices of organophosphate toxicity. The correlation between social stress and malathion toxicity was less well defined. Chickens with low antibody response preexposed to high social stress were most resistant to organophosphate toxicity. 相似文献
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Two field occurrences of protein-deficiency disease were reported in turkeys and chickens. The disease caused unthriftiness, poor growth, and the exhibition of pica in flocks of 15-week-old pedigree large white turkeys, and it resulted in a sharp drop (18%) in egg production in a flock of 60-week-old white leghorn layers. In each case, the disease was cured by replacing the protein-deficient diet with a protein-sufficient one. 相似文献
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Chicken kidney cells, derived from the eggs of white leghorn chickens that had serological evidence of prior exposure to both adenovirus and the adeno-associated virus (AAV), produced AAV antigenic proteins upon challenge with purified adenovirus. Antigen was detected by indirect immunofluorescence using monoclonal antibody to AAV. The number of fluorescent cells were few and did not increase during the course of adenovirus infection. Similar results were obtained using cells prepared from specific-pathogen-free chicks with no previous exposure to adenovirus or AAV. It is postulated that the avian AAV can exist as a latent infection in the germ line of chickens. 相似文献
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Myeloblastosis-associated virus type 1 (MAV-1) is an exogenous avian retrovirus with oncogenic potential. MAV-1 was detected in young chicks hatching from eggs produced by an experimental genetic line of egg-type chickens. Transmissibility of MAV-1 had not been documented previously. This investigation was intended to partially characterize the virus involved and to study its transmissibility and oncogenicity in naturally and contact-infected chickens. Commercially produced white and brown layer pullets free of exogenous avian leukosis viruses were commingled at hatch with naturally MAV-1-infected chickens. The original MAV-1-infected chickens were discarded after approximately 8 wk, and the contact-exposed chickens were maintained in isolation for 36 wk. Young specific-pathogen-free (SPF) single comb white leghorn chickens were added to the group to study possible horizontal transmission of MAV-1 in young chickens. Upon weekly virus isolation attempts, MAV-1 was readily isolated from the contact-exposed white layers but not from the brown layers between 36 and 53 wk of age (18 wk in total). Three-week-old SPF chickens were readily infected with MAV-1 by contact as early as 1 wk postexposure. Throughout 22 hatches derived from the white and brown MAV-1-contact-exposed layers (between 36 and 53 wk of age), MAV-1 was frequently detected in the white layer progeny, whereas the virus was seldom isolated from the progeny produced by the brown layers during the same 18-wk period. MAV-1 induced a persistent infection in some of the SPF chickens that were exposed by contact at 3 wk of age. Gross tumors were not detected in any of the originally infected experimental chickens at 8 wk of age, in the contact-exposed brown or white layers at the termination of the study at 53 wks of age, or in the contact-exposed SPF chickens at the end of the study at 12 wk of age. Exogenous avian leukosis-related viruses may still be detected in egg-type chickens, emphasizing the importance of thorough screening before incorporation of experimental genetic material into commercial genetic lines of egg-type chickens. 相似文献
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Richard OSEI‐AMPONSAH Boniface B. KAYANG Augustine NAAZIE Yaa D. OSEI Issaka A. K. YOUSSAO Valentine C. YAPI‐GNAORE Michèle TIXIER‐BOICHARD Xavier ROGNON 《Animal Science Journal》2010,81(3):297-303
The characterization of indigenous animal genetic resources is a requisite step in providing needed information for the conservation of useful genotypes against future needs. Thus, in this study, 22 microsatellite markers were used to genotype 114 local chickens from the Forest (n = 59) and Savannah (n = 55) eco‐zones of Ghana and the results compared to those of the ancestral red junglefowl (n = 15) and two European commercial chicken populations – a broiler (n = 25) and white leghorn (n = 25). A total of 171 alleles were observed, with an average of 7.8 alleles per locus. The local Ghanaian chickens showed higher diversity in terms of the observed number of alleles per locus (6.6) and observed heterozygosity (0.568) compared with the combined control populations (6.0 and 0.458, respectively). However, Wright's F‐statistics revealed negligible genetic differentiation (FST) in local Ghanaian chicken populations. In addition, 65% of the Savannah chickens were inferred to be more likely from the Forest, suggesting a south‐north dispersal of chickens from their probable original location in the Forest zone to the Savannah areas. It is concluded that the Forest and Savannah chickens of Ghana are a single, randomly mating unselected population, characterized by high genetic diversity and constitute a valuable resource for conservation and improvement. 相似文献
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A clone bank of Mycoplasma gallisepticum (MG) strain A5969 DNA was prepared in the expression vector phage lambda gt11. Approximately 75% of the resulting phages were recombinants, based upon the insertional inactivation of the lacZ gene of the vector. Clones were screened immunologically with serum prepared from specific-pathogen-free white leghorn chickens that had been infected with aerosolized MG. Approximately 250 clones, or less than 1% of the recombinant phage, reacted positively to various degrees with the test serum and failed to react with serum from uninfected specific-pathogen-free control chickens. A single clone was chosen at random for comparison with a vector control by western immunoblot, revealing a polypeptide of 140,000 molecular weight in the clone profile but not the control profile that reacted with immune serum. Clones expressing MG antigens recognized during infection may provide an improved means for antigen preparation for serologic diagnosis of mycoplasmosis. 相似文献
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Groups of approximately 20 one-day-old chickens were inoculated with G-4260, the reference strain of avian nephritis virus (ANV), or saline. Based on mortality rates from severe nephritis in comparable experiments, light Sussex chickens generally were more susceptible than Rhode Island red (RIR) chickens. Mortality was greater in those given broiler starter than those given other feeds, and was greater when light Sussex chickens were given broiler starter feed and cold-stressed at 15 +/- 1 C for 2 hr daily during the first week rather than brooded normally. Inoculation with G-4260 either orally or by intraperitoneal injection produced similar results in RIR chickens. Thirty-three inoculated chickens died of severe nephritis between 4 and 12 days postinoculation, and 24 (73%) of them had visceral urate deposits. Inoculated inbred white leghorn Line 15 chickens with maternal antibody to ANV were brooded normally and given broiler feed: they were susceptible to infection as evidenced by subsequent histological lesions in the kidneys and serology, but mortality was not a feature. There were no deaths from nephritis in inoculated non-inbred white leghorn chickens free of maternal antibody to ANV that were given broiler feed and brooded normally. These results have implications in standardizing experimental conditions for the study of mortality induced by G-4260 and similar viruses. 相似文献
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An outbreak of urolithiasis characterized by high mortality and emaciation in a flock of leghorn pullets is reported. The etiology was not ascertained. Other signs were swollen feet associated with articulate gout. Visceral gout, atrophy, or irregular hypertrophy of the kidneys were also observed. Many birds had one or both ureters enlarged with white uroliths. Microscopic lesions were urate granulomas, necrosis and loss of kidney parenchyma associated with tubular dilation, and edematous and fibrotic interstitium. 相似文献