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111.
尾脂沉积能力在脂尾型绵羊和瘦尾型绵羊问存在很大的差异,但其沉积脂肪的遗传特性与分子机制仍不明晰。为此,本研究选择尾型极端差异的阿勒泰羊(巨型脂臀)、湖羊(短脂尾)和黑萨福克羊(长瘦尾),采用PCR-RFLP方法检测绵羊X染色体59194976位点多态性,分析其与尾(臀)脂沉积能力的相关性。结果表明:在阿勒泰羊群体中G等位基因属优势等位基因,其两等位基因比值(G/A)分别是湖羊和黑萨福克羊的6倍和68倍,且G等位基因在阿勒泰羊中趋于纯合。卡方检验结果表明,阿勒泰羊在该位点均处于Hardy-Weinberg平衡状态(p〉0.05),而湖羊和黑萨福克羊在该位点均处于Hardy-Weinberg极不平衡状态(p〈0.01)。以上结果提示,绵羊x染色体59194976位点SNP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
112.
Evaluation of grain yield and its components in wheat cultivars and landraces under near optimal and drought conditions 总被引:3,自引:0,他引:3
In a 2-years experiment, 30 wheat cultivars and 21 landraces from different countries were tested under near optimum and drought
stress conditions. Plant height, number of sterile spikelets per spike, spikelets per spike, number of kernels per spike,
kernel weight per spike, 1000 kernel weight and grain yield were evaluated. The number of kernels per spike, 1000 kernel weight
and especially yield were more sensitive to drought stress in the cultivars than plant height and number of spikelets per
spike, while in the landraces these traits did not differ under drought stress compared to near optimum conditions. The average
yield of cultivars was significantly better than the average yield of landraces under near optimum as well as drought stress
conditions. Path coefficient analysis showed that for cultivars under near optimum conditions there was no significant direct
association of any of the analysed characters with yield, while under drought stress conditions, number of kernels per spike
had a significant positive direct effect. Under drought stress conditions, the number of sterile spikelets displayed a negative
direct effect, while kernel weight per spike had a positive direct effect on yield. Hierarchical cluster analysis was used
as a tool to classify cultivars and landraces according to their yield ability under near optimum and drought stress conditions.
Among the cultivars, two groups out of five and among one of three in the landraces were characterised by high yields in both
near optimum as well as under drought stress conditions. These genotypes may serve as sources of germplasm for breeding for
drought tolerance.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
113.
Staatsoberförster i. R. A. Zimmermann 《Journal of pest science》1933,9(2):26-27
Ohne Zusammenfassung
Mit 2 Abbildungen. 相似文献
114.
115.
116.
Matthäi 《Forstwissenschaftliches Centralblatt》1922,44(11):405-419
Ohne Zusammenfassung 相似文献
117.
Matthäi 《Forstwissenschaftliches Centralblatt》1922,44(12):463-484
Ohne Zusammenfassung 相似文献
118.
A. Kovačić I. Listeš C. Vučica L. Kozačinski I. Tripković K. Šiško‐Kraljević 《Zoonoses and public health》2013,60(4):269-276
Consumption of poultry contaminated with Campylobacter jejuni has been recognized worldwide as the leading cause of campylobacteriosis. Therefore, the aim of our study was to investigate the prevalence and genotype diversity of Campylobacter jejuni in poultry meat intended for consumption in Split and Dalmatia County, which is the second biggest County in Croatia. Furthermore, we also wanted to discover possibly stable clones of C. jejuni appearing in different samples and periods of time, which would indicate their ability to persist in or adapt to poultry. In the period from March 2008 until June 2010, 834 samples of poultry from various sources were examined using a surface swab technique. Isolation of C. jejuni was performed by Preston broth and Karmali agar. Identification of the isolates was carried out using biochemical tests. C. jejuni was found in 84 of 574 chicken samples (14.6%) and in nine of 260 samples of turkey (3.5%). Pulse‐field gel electrophoresis (PFGE) was used to analyse 61 obtained isolates using SmaI and KpnI. Of 22 different macrorestriction profiles (MRP) that were found, five were detected in poultry from both different locations and periods of time. Samples from 11 locations were found to be contaminated with more than two different genotypes of C. jejuni. Interestingly, the same MRP were found both in poultry declared to be of domestic origin and in the poultry imported from abroad. The prevalence of C. jejuni in poultry samples was in accordance with previously reported results. Genotypic analysis indicated that the population of C. jejuni in Split and Dalmatia County was diverse and that multiple strains of C. jejuni could be found in the same poultry samples. Furthermore, the same genotypes were identified from the samples obtained from different locations and periods of time, which could support the theory of a global existence of certain MRP that are able to persist in or adapt to poultry. 相似文献
119.
抗热应激药物对肉仔鸡血浆激素及组织学的影响 总被引:1,自引:0,他引:1
本试验研究了抗应激药物(抗应激Ⅱ、Ⅲ号)对人工高温下肉仔鸡血浆部分激素和组织学的影响。分别于升温至28℃、32℃、36℃后半小时及36℃维持5天后采血测定。结果表明:抗热应激Ⅱ和Ⅲ号均可降低热应激时肉仔鸡血浆中的ACTH、GLU(P<0.05)和皮质酮(Ⅲ号,P<0.01);使温度上升期间血浆T3浓度增加(P<0.05)而T4降低(P<0.05),使在36℃维持5天的血浆T3、T4含量均降低(P<0.05);升高血中的淋巴细胞,而降低中性粒细胞;减轻热应激时主要器官的组织学改变。提示抗应激Ⅱ、Ⅲ号药物具有较好的抗热应激效果,以饲料中添加0.225%的Ⅲ号效果最佳。 相似文献
120.
Rough vaccines in animal brucellosis: structural and genetic basis and present status 总被引:14,自引:0,他引:14
Moriyón I Grilló MJ Monreal D González D Marín C López-Goñi I Mainar-Jaime RC Moreno E Blasco JM 《Veterinary research》2004,35(1):1-38
Brucellosis control and eradication requires serological tests and vaccines. Effective classical vaccines (S19 in cattle and Rev 1 in small ruminants), however, induce antibodies to the O-polysaccharide of the lipopolysaccharide which may be difficult to distinguish from those resulting from infection and may thus complicate diagnosis. Rough attenuated mutants lack the O-polysaccharide and would solve this problem if eliciting protective immunity; the empirically obtained rough mutants 45/20 and RB51 have been used as vaccines. Strain 45/20 is reportedly unstable and it is not presently used. RB51 is increasingly used instead of S19 in some countries but it is rifampicin resistant and its effectiveness is controversial. Some controlled experiments have found good or absolute protection in adult cattle vaccinated orally (full dose) or subcutaneously (reduced dose) and in one field experiment, RB51 was reported to afford absolute protection to calves and to perform better than S19. Controlled experiments in calves, however, have shown reduced doses of RB51 to be ineffective, full doses only partially effective, and RB51 less effective than S19 against severe challenges. Moreover, other observations suggest that RB51 is ineffective when prevalence is high. RB51 is not useful in sheep and evidence in goats is preliminary and contradictory. Rough mutants obtained by molecular biology methods on the knowledge of the genetics and structure of Brucella lipopolysaccharide may offer alternatives. The B. abortus manBcore (rfbK) mutant seems promising in cattle, and analyses in mice suggest that mutations affecting only the O-polysaccharide result in better vaccines than those affecting both core and O-polysaccharide. Possible uses of rough vaccines also include boosting immunity by revaccination but solid evidence on its effectiveness, safety and practicality is not available. 相似文献