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Association analysis of novel polymorphisms in 2′, 5′‐oligoadenylate synthetase gene with reproductive traits in indigenous and cross‐bred cattle of Indian Origin 
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下载免费PDF全文 R Alex KP Ramesha U Singh S Kumar RR Alyethodi R Deb S Rai S Sharma GS Sengar A Kumar B Prakash 《Reproduction in domestic animals》2018,53(2):442-449
2′, 5′‐Oligoadenylate synthetases (OAS) are important components of an interferon‐mediated antiviral pathway. No polymorphisms in exonic regions of bovine OAS1 gene have been identified and associated with reproduction traits. The objective of the study was to detect and evaluate the effects of mutations in exonic region of bovine OAS1 gene with reproduction traits in cattle. DNA samples collected from 250 individual cows of two Indian dairy breeds (Sahiwal and Frieswal) of cattle were used in the study. The genetic variants of the OAS1 gene were identified with polymerase chain reaction–single‐strand conformation polymorphism (PCR‐SSCP) and sequence analysis using seven set of primer pairs. The PCR‐SSCP analysis revealed polymorphism in the fragments comprising of exon 2, exon 5 and first fragment of exon 6 while the fragments of exons 1, 3, 4 and second fragment of exon 6 were monomorphic in Sahiwal and Frieswal cattle. The mutations in the amplified region comprising of exon 2 were found to have significant association with age at first breeding and calving, service period, dry period and pregnancy rate. Significant associations were found between SNPs in the exon 5 and service and dry periods of the animal, whereas the genetic variants in the first fragment of the exon 6 showed significant association with age at first breeding and calving. To our knowledge, this study demonstrated for the first time that the polymorphisms in OAS1 gene were associated with reproductive traits and it can be chosen as a candidate gene for improvement of reproductive performance of cattle. 相似文献
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Summary Improved oil, protein and fibre contents are associated with light seed colour in rapeseed but the lack of reliable and efficient methods to measure seed colour has hindered breeding efforts for this trait. The feasibility of using light reflectance to assess seed colour in Brassica napus was examined using scanning light reflectance spectrophotometry and near infrared reflectance (NIR). Light reflectance by seed samples from 30 doubled haploid (DH) lines segregating for seed colour increased as the wavelength of the illuminating light in the scanning spectrophotometer increased between 550 and 650 nm. The largest reflectance values were measured for the yellow seed samples; the brown seed samples were intermediate and the black seed samples had the lowest reflectance values. The areas under the reflectance curves were used to transform the spectra to single values. Average light reflectance area values for the seed colour classes were significantly different from each other. The DHs and their corresponding light reflectance area values were also used to calibrate a NIR analyzer modified with 670 and 710 nm filters. The best calibration curve used three wavelengths (670, 2190 and 2208 nm) and had a multiple correlation coefficient of 0.987. Light reflectance area values determined with the calibrated NIR analyzer for 30 randomly selected breeding lines could be used to categorize the colour of the seed samples with no discrepancies between the visual and instrument classifications. The results indicate that NIR can be used to assess seed colour in rapeseed. 相似文献
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Analysis of the costs of veterinary education and factors associated with financial stress among veterinary students in Australia 下载免费PDF全文
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To investigate the course‐related and other costs involved in obtaining a veterinary education in Australia and how these costs are met. The study also aimed to identify sociodemographic and course‐related factors associated with increased financial stress.Methods
Students from seven Australian veterinary schools were surveyed using an online questionnaire. A total of 443 students participated (response rate 17%). Responses to survey items relating to finances, employment and course‐related costs were compared with sociodemographic factors and prior research in the area of student financial stress.Results
Respondents reported spending a median of A$300 per week on living costs and a median of A$2,000 per year on course‐related expenses. Over half of respondents received the majority of their income from their parents or Youth Allowance (56%). A similar proportion (55%) reported that they needed to work to meet basic living expenses. Circumstances and sociodemographic factors linked to perceived financial stress included requiring additional finances to meet unexpected costs during the course; sourcing additional finances from external loans; an expected tuition debt at graduation over A$40,000; being 22 years or older; working more than 12 hours per week; living costs above A$300 per week; and being female.Conclusion
The costs involved in obtaining a veterinary education in Australia are high and over half of respondents are reliant on parental or Government income support. Respondents with certain sociodemographic profiles are more prone to financial stress. These findings may have implications for the psychological health, diversity and career plans of veterinary students in Australia. 相似文献27.
Breeding for high symbiotic nitrogen (N) fixation (SNF) in common bean (Phaseolus vulgaris L.) is expected to contribute to reduced application of chemical fertilizers in cropping systems involving common bean. The magnitude of variation and the genetic and phenotypic correlation among seed yield, SNF, estimated as the percentage of nitrogen derived from atmosphere, and related traits were studied in a population of 140 F4-derived F5 recombinant inbred lines, developed from a cross between low- and high-SNF bean genotypes ‘Sanilac’ and ‘Mist’, respectively. The experiment was conducted in a total of five location-years in Ontario, Canada, from 2011 to 2013. These location-years were grouped into stress- and optimum moisture test sites, based on the total precipitation during the growing season. In each test site two nitrogen supply management strategies, SNF-dependent and N fertilizer-dependent, were simulated separately in the field by inoculating the seed with a commercial Rhizobium leguminosarum bv. phaseoli and by application of N fertilizers at 100 kg ha?1, respectively. The genetic variation was significant for seed yield, SNF and related traits. The heritability of the traits ranged from 14 to 71% and 4 to 25% in optimum moisture and in stress environments, respectively. No significant correlation between SNF and seed yield indicated that selection for high SNF does not necessarily lead to greater seed yield and that selection for both traits should be performed simultaneously. 相似文献
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J. D. Murray T. E. Michaels C. Cardona A. W. Schaafsma K. P. Pauls 《Plant Breeding》2004,123(5):474-479
A population of 108 common bean recombinant inbred lines (RILs) (F5:6‐9), derived from a leafhopper (Empoasca fabae and E. kraemeri)‐susceptible cultivar (‘Berna’) and a leafhopper‐resistant line (EMP 419) was used to identify molecular markers genetically linked to leafhopper resistance and seed weight. Bulked segregant analysis and quantitative trait analysis identified eight markers that were associated with resistance to E. fabae, and four markers that were associated with E. kraemeri resistance. Three markers were associated with resistance to both species. A partial linkage map of the bean genome was constructed. Composite interval mapping identified quantitative trait loci (QTL) for resistance to both leaf hopper species on core‐map linkage groups B1, B3 and B7. QTL for seed weight were found close to the locus controlling testa colour and an α‐phaseolin gene. 相似文献
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The levels of individual and total alkenyl glucosinolates in seeds of microspore-derived spontaneous diploid plants from low by high and low by low glucosinolate parent crosses were examined to assess the utility of haploidy in canola breeding. The distributions of lines in the populations supported previous proposals that alkenyl glucosinolate levels are under multigenic control. Levels of all of the individual glucosinolates were positively correlated and were significantly reduced in canola-quality material in comparison to rapeseed-quality material. The populations of microspore-derived lines from low × high crosses were skewed to high glucosinolate levels but the population from a low × low glucosinolate cross had a greater proportion of low glucosinolate lines. The former observations can be explained in terms of the dominance of genes for high glucosinolate levels in Brassica napus. The present findings contradict previous reports that androgenic lines have higher glucosinolate content than the parents and in fact, haploidy may select for low glucosinolate lines when crosses between low glucosinolate parents are used. 相似文献
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Lerat S England LS Vincent ML Pauls KP Swanton CJ Klironomos JN Trevors JT 《Journal of agricultural and food chemistry》2005,53(5):1337-1342
A method for quantification of recombinant DNA for Roundup Ready (RR) corn and RR soybean in soil samples is described. Soil DNA from experimental field samples was extracted using a soil DNA extraction kit with a modified protocol. For the detection and quantification of recombinant DNA of RR corn and RR soybean, a molecular beacon and two pairs of specific primers were designed to differentially target recombinant DNA in these two genetically modified crops. Soil DNA extracts were spiked with RR corn or RR soybean DNA, and recombinant DNA was quantified using real-time PCR with a molecular beacon. As few as one copy of RR corn genome or one copy of RR soybean genome was detected in the soil DNA extract. 相似文献