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1.
绵羊7号染色体46843356位点多态性与尾脂沉积相关性研究   总被引：1，自引：0，他引：1  
为探讨绵羊7号染色体上46843356位点多态性与绵羊尾脂沉积的关系,以尾型极端差异的阿勒泰羊、小尾寒羊、中国美利奴细毛羊以及萨福克羊为研究对象,利用PCR-RFLP检测该位点在群体中的多态性。结果表明:46843356位点在尾脂沉积能力较差的中国美利奴细毛羊和萨福克羊群体以AA基因型为主,而尾脂沉积能力强的阿勒泰羊群体则以GG和GA基因型为主,阿勒泰羊和小尾寒羊G/A等位基因频率比值为2.48和4.22,分别是萨福克羊的83倍和141倍。卡方检验结果表明,阿勒泰羊和小尾寒羊在该位点上处于Hardy-Weinberg平衡状态(P>0.05),而中国美利奴细毛羊和萨福克羊在该位点上处于Hardy-Weinberg极度不平衡状态(P<0.01)。以上结果提示,绵羊7号染色体上46843356SNP位点在脂尾(臀)与瘦尾绵羊群体中存在较大差异,可作为理想的分子标记应用于高、低脂绵羊品种选育。  相似文献   

2.
为了研究碱基突变对miRNA成熟加工的影响,以绵羊let-7c(oar-let-7c)为研究对象,探讨了其前体序列在阿勒泰羊和中国美利奴羊(军垦型)群体中的突变情况,及相关突变对oar-let-7c前体二级结构和稳定性的影响。结果表明:oar-let-7c前体序列在阿勒泰羊和中国美利奴羊(军垦型)群体中可检测到1处CT突变,该突变位于oar-let-7c成熟序列下游,且在阿勒泰羊群体中以C等位基因为主,而在中国美利奴羊(军垦型)群体中则以T等位基因为主,该突变改变了oar-let-7c前体二级结构且使其自由能值升高了46.89 kJ/mol,推测该突变将对oar-let-7c成熟加工产生影响,进而影响oar-let-7c在阿勒泰羊和中国美利奴羊(军垦型)体内的水平。  相似文献   

3.
绵羊跨膜蛋白154基因(Transmembrane protein 154,TMEM154)多态性与进行性肺炎的易感或抗性有关。本研究以绵羊TEME154基因第2外显子G103A(E35/K35)位点SNP为候选分子标记,利用PCR直接测序法检测TEME154基因型,对该基因在新疆地区8个绵羊品种(阿勒泰羊、哈萨克羊、巴音布鲁克羊、多浪羊、策勒黑羊、巴什拜羊、德国美利奴羊和中国美利奴羊)的遗传多态性进行分析。结果表明:绵羊TMEM154基因在第2外显子103bp处发生了G-A突变,PCR测序共检测到3种基因型;即AA、AG和GG,G103A位点的GG(E35)基因型与绵羊进行性肺炎的高敏感性相关,在阿勒泰羊、哈萨克羊、巴音布鲁克羊、多浪羊、策勒黑羊和巴什拜羊群体中属于优势基因型,而在中国美利奴羊和德国美利奴羊群体中比例较低。方差分析表明,该位点的基因型频率在阿勒泰羊、哈萨克羊、巴音布鲁克羊、多浪羊、策勒黑羊和巴什拜羊等进行性肺炎高敏感群体和中国美利奴羊和德国美利奴羊等低敏感群体间存在显著差异(P0.05)。本研究结果提示,绵羊TMEM154基因第2外显子G103A位点多态性在进行性肺炎高敏感与低敏感的绵羊群体中分布存在较大差异,该SNP可作为一个理想的分子标记应用于绵羊的抗病育种。  相似文献   

4.
试验旨在分析6个绵羊群体骨形态蛋白受体1B(bone morphogenetic protein receptor-1B,BMPR-1B)基因多态性,为绵羊繁殖力的标记辅助选择和育种提供理论依据。采集新吉细毛羊、中国美利奴羊(无角型)、东北细毛羊、杜×寒杂交羊(F1)、杜×寒杂交羊(F3)、白头杜泊羊6个绵羊群体共381只个体的血样,通过PCR-RFLP技术检测BMPR-1B基因多态性,并用DNAStar软件预测蛋白质二级结构,利用Excel 2003软件计算基因频率、基因型频率、Hardy-Weinberg平衡,以及遗传多样性参数(杂合度(He)、纯合度(Ho)、有效等位基因数(Ne)和多态信息含量(PIC))。结果显示,新吉细毛羊、东北细毛羊、中国美利奴羊(无角型)、白头杜泊羊BMPR-1B基因均不存在多态性;杜×寒杂交羊(F1)、杜×寒杂交羊(F3)具有多态性,存在3种基因型:++、B+和BB。杜×寒杂交羊(F1)χ2值达到显著水平,处于Hardy-Weinberg不平衡状态;杜×寒杂交羊(F3)χ2值未达到显著水平,处于Hardy-Weinberg平衡状态。杜×寒杂交羊(F1)、杜×寒杂交羊(F3)的PIC分别为0.311和0.264,为中度多态。推测BMPR-1B基因不是新吉细毛羊、东北细毛羊、中国美利奴羊(无角型)、白头杜泊羊4个绵羊群体多胎性状的主效基因,但可作为杜×寒杂交羊(F1)、杜×寒杂交羊(F3)多胎性状的主效基因。  相似文献   

5.
为了探究KAP2基因在不同绵羊群体的多态性,本次试验利用PCR-SSCP的方法,分析新吉细毛羊、道赛特羊和小尾寒羊的基因型和突变位点,并对KAP2基因编码区序列进行多态性分析。结果:新吉细毛羊基因序列第292位点处发生T→C的突变,绵羊群体基因型可分为AA、AB、BB基因型;A基因频率中新吉细毛羊、道赛特羊、小尾寒羊分别为0.3261、0.3696、0.5217,B基因频率中新吉细毛羊、道赛特羊、小尾寒羊分别为0.6739、0.6304、0.4783,AA基因型频率新吉细毛羊、道赛特羊、小尾寒羊分别为0.2609、0.3043、0.3913,AB基因型频率新吉细毛羊、道赛特羊、小尾寒羊分别为0.1304、0.2174、0.2609,BB基因型频率新吉细毛羊、道赛特羊、小尾寒羊分别为0.6087、0.4783、0.3478。结论:绵羊群体分为AA、AB、BB基因型,BB基因型为优势基因型。  相似文献   

6.
试验旨在研究Toll样受体2（Toll-like receptor,TLR2）基因的多态性及其与中国美利奴羊布鲁氏菌病易感性的相关性。利用生物信息学方法对NCBI上公布的绵羊TLR2基因序列进行比对,选出多态位点丰富的片段进行扩增,运用PCR-SSCP的方法对206个中国美利奴布鲁氏菌病阴性样本和80个中国美利奴羊布鲁氏菌病阳性样本进行TLR2基因的多态性检测,然后对不同等位基因的PCR产物进行测序,确定该基因的多态性位点,经卡方检验分析每个SNP位点的等位基因频率、基因型频率及其多态性与布鲁氏菌病易感性的相关性,利用生物信息学软件分析RNA二级结构及蛋白质的二级结构。结果表明,在279 bp的序列中共检测到3个SNPs,分别为：C1731T、G1737C和G1749T,均未引起对应氨基酸的改变,属于无义突变。这些位点在病例组和对照组之间的等位基因频率及基因型频率均不存在显著差异（P>0.05）。各突变位点均能引起RNA二级结构和最小自由能的改变,而蛋白质的二级结构均未改变。由此得出,中国美利奴羊TLR2基因的3个SNPs位点（C1731T、G1737C和G1749T）与中国美利奴羊布鲁氏菌病易感性无相关性。  相似文献   

7.
试验旨在研究Toll样受体2(Toll-like receptor,TLR2)基因的多态性及其与中国美利奴羊布鲁氏菌病易感性的相关性。利用生物信息学方法对NCBI上公布的绵羊TLR2基因序列进行比对,选出多态位点丰富的片段进行扩增,运用PCR-SSCP的方法对206个中国美利奴布鲁氏菌病阴性样本和80个中国美利奴羊布鲁氏菌病阳性样本进行TLR2基因的多态性检测,然后对不同等位基因的PCR产物进行测序,确定该基因的多态性位点,经卡方检验分析每个SNP位点的等位基因频率、基因型频率及其多态性与布鲁氏菌病易感性的相关性,利用生物信息学软件分析RNA二级结构及蛋白质的二级结构。结果表明,在279bp的序列中共检测到3个SNPs,分别为:C1731T、G1737C和G1749T,均未引起对应氨基酸的改变,属于无义突变。这些位点在病例组和对照组之间的等位基因频率及基因型频率均不存在显著差异(P0.05)。各突变位点均能引起RNA二级结构和最小自由能的改变,而蛋白质的二级结构均未改变。由此得出,中国美利奴羊TLR2基因的3个SNPs位点(C1731T、G1737C和G1749T)与中国美利奴羊布鲁氏菌病易感性无相关性。  相似文献   

8.
不同绵羊品种FGF5基因的多态性分析   总被引：10，自引：0，他引：10  
根据人和小鼠成纤维细胞生长因子5（FGFS）基因的同源序列设计引物对绵羊基因组进行PCR扩增，将扩增片段进行克隆和测序，并与人和小鼠的成纤维细胞生长因子5基因序列进行同源性比较，确定扩增的片段为绵羊的FGF5基因片段。采用PCR-SSCP技术分析了FGF5基因外显子在小尾寒羊、湖羊、藏羊、中国美利奴等4个绵羊品种的多态性。结果表明：FGF5基因在P1和P2引物扩增片段中存在PCR-SSCP多态性。经克隆测序分析，位于外显子1的引物1扩增产物存在G→T突变，该突变位点使编码的氨基酸发生A→S的改变；引物2扩增产物发生了碱基序列C→T的突变，这一突变位点没有引起编码氨基酸的改变，属于同义突变。对不同绵羊品种的基因型和基因频率统计结果表明，引物1扩增产物小尾寒羊、湖羊、藏羊以等位基因A为主，而中国美利奴羊则以等位基因B为主，且各群体均处于Hardy-Weinberg平衡；引物2扩增产物小尾寒羊、湖羊、中国美利奴羊均以等位基因E为主，而藏羊的基因型频率与其它品种有显著差异，中国美利奴羊在引物2位点的基因频率处于Hardy-Weinberg不平衡状态。  相似文献   

9.
试验旨在分析6个绵羊群体骨形态蛋白受体1B（bone morphogenetic protein receptor-1B，BMPR-1B）基因多态性，为绵羊繁殖力的标记辅助选择和育种提供理论依据。采集新吉细毛羊、中国美利奴羊（无角型）、东北细毛羊、杜×寒杂交羊（F1）、杜×寒杂交羊（F3）、白头杜泊羊6个绵羊群体共381只个体的血样，通过PCR-RFLP技术检测BMPR-1B基因多态性，并用DNAStar软件预测蛋白质二级结构，利用Excel 2003软件计算基因频率、基因型频率、Hardy-Weinberg平衡，以及遗传多样性参数（杂合度（He）、纯合度（Ho）、有效等位基因数（Ne）和多态信息含量（PIC））。结果显示，新吉细毛羊、东北细毛羊、中国美利奴羊（无角型）、白头杜泊羊BMPR-1B基因均不存在多态性；杜×寒杂交羊（F1）、杜×寒杂交羊（F3）具有多态性，存在3种基因型：++、B+和BB。杜×寒杂交羊（F1）χ2值达到显著水平，处于Hardy-Weinberg不平衡状态；杜×寒杂交羊（F3）χ2值未达到显著水平，处于Hardy-Weinberg平衡状态。杜×寒杂交羊（F1）、杜×寒杂交羊（F3）的PIC分别为0.311和0.264，为中度多态。推测BMPR-1B基因不是新吉细毛羊、东北细毛羊、中国美利奴羊（无角型）、白头杜泊羊4个绵羊群体多胎性状的主效基因，但可作为杜×寒杂交羊（F1）、杜×寒杂交羊（F3）多胎性状的主效基因。  相似文献   

10.
绵羊FGF5基因Exon 3多态性对毛用性状的影响   总被引：1，自引：0，他引：1  
为探寻不同细毛羊品种FGF5基因多态性及其对毛用性状的影响,采用PCR-SSCP方法对苏博美利奴羊和东北细毛羊两个群体的FGF5基因Exon 3区进行了多态性分析,并在苏博美利奴羊群体中对不同基因型个体与其毛用性状进行了差异显著性分析。结果表明:苏博美利奴羊群体FGF5基因Exon 3区存在5种基因型,分别是DD、EE、FF、DE和EF,而东北细毛羊群体只存在DD、EE和DE三种基因型;苏博美利奴羊F等位基因由CDs区c.618和c.733多态位点构成,其中c.733位点C-G突变导致E等位基因型个体氨基酸L-V变异。苏博美利奴羊群体只有FF基因型个体在产毛量指标上显著高于DD基因型个体(P0.05)。不同毛用绵羊品种FGF5基因多态性及其与毛用性状相关性的研究可为利用FGF5基因进行毛用性状选育奠定基础。  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

13.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

14.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

15.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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16.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

17.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

18.
A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L3) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L3 developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.  相似文献   

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