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231.
Nisha Aravind Mike Sissons Narelle Egan Christopher M. Fellows Jaroslav Blazek Elliot P. Gilbert 《Cereal Chemistry》2012,89(2):84-93
β‐Glucan is known to have valuable properties for preventative health and is finding widespread use in foods. This study investigated the benefit of adding a commercial source of β‐glucan, Barley Balance (BB) flour, as a functional ingredient in spaghetti. Durum wheat semolina was substituted with BB at levels of 7.5, 15, and 20%, from which spaghetti was prepared on a laboratory scale. The substitution of BB increased the β‐glucan content of semolina from 0.3 to 6% in uncooked and 8% in cooked pasta. Antioxidant activity (measured by 2,2‐diphenyl‐1‐picrylhydrazyl) increased with BB and did not decline significantly on processing and cooking. Compared with the control, 7.5% BB had no or minimal effect on pasta cooking loss, stickiness, water absorption, aroma, and sensory texture. However, at higher doses, pasta became less yellow and more brown, firmer, of inferior aroma, more rubbery, and chewy, but less floury to the mouth. The extent of starch digestion decreased with increasing quantities of BB, suggesting that BB may lower glycemic index, with microscopy data suggesting that this decrease was mediated through the development of a more intensive fiber or fiber/protein matrix retarding enzymatic access to starch granules. 相似文献
232.
Mike Levy Cate Dewey Alfons Weersink Florence Mutua Natalie Carter Zvonimir Poljak 《Tropical animal health and production》2014,46(5):797-808
The purpose of this research is to assess how season, ADG, opportunity costs of farm-grown feeds, pig weight, and butcher price variation impact the economic potential of semi-intensive pig rearing. We developed a unique algorithm that emulates least-cost pig feeding and used it to assess the impact of the aforementioned factors on farmers’ maximum revenue and profit potential when pigs are sold to local butchers in western Kenya. When considered as independent factors influencing feed costs to grow a pig to a market weight of 30 kg, variation in ADG, opportunity cost of feed, and weaning season resulted in feed cost differences of up to 982, 947, and 379 Kenyan shillings (KES), respectively. The variation in revenues attributable to butcher or butcher negotiation and seasonal variance of butcher prices for a 30 kg pig was 744 and 225 KES, respectively. Feed items most commonly chosen for least-cost feed rations were small dried fish, cooked ground maize, whole maize, millet, cassava foliage, sweet potato vines, bone meal, avocado, and mango. Smallholder farmers who can feed pigs to reach higher ADG have lower opportunity costs of feeds and/or who effectively bargain with butchers can benefit from semi-intensive pig rearing. Farmers without access to at least some zero-cost feeds and farmers with opportunity costs of feeds exceeding 50 % of the market price will not earn positive returns from semi-intensive pig rearing. 相似文献
233.
黑龙江大兴安岭雷击火概率预测模型研究 总被引:1,自引:0,他引:1
结合黑龙江大兴安岭雷击火发生特点及该地区的气象条件,引用加拿大天气指标(FWI)系统,使用2005年至2010年每日的闪电定位数据、天气数据、雷击引发的火灾数据,利用二元Logistic回归模型,采用全部进入法建立回归模型,最后检验分析显示:模型拟合效果较为理想,为预测黑龙江大兴安岭地区雷击火发生概率提供依据。 相似文献
234.
Dunne M 《Science (New York, N.Y.)》2006,312(5772):374-376
235.
Mike Winehnd 《中国家禽》2009,31(16)
在母鸡生产周期内加入不同的公鸡以维持或增加种蛋的受精率水平,这对于平养方式下的种鸡群而言,是一种行之有效的方法.从图1可以看出,鸡群受精率的水平在40周龄时达到高峰,此后会呈现出下降的走势. 相似文献
236.
Ryan L Jeon Caroline Gilbert Jian Cheng Austin M Putz Mike K Dyck Graham S Plastow Frederic Fortin PigGen Canada Jack C M Dekkers John C S Harding 《Journal of animal science》2021,99(8)
Disease resilience refers to the productivity of an animal under disease. Given the high biosecurity of pig nucleus herds, traits that can be measured on healthy pigs and that are genetically correlated with disease resilience, that is, genetic indicator traits, offer a strategy to select for disease resilience. Our objective was to evaluate mitogen stimulation assays (MSAs) on peripheral blood mononuclear cells (PBMCs) from young healthy pigs as genetic indicators for disease resilience. Data were from a natural disease challenge in which batches of 60 or 75 naïve Yorkshire × Landrace piglets were introduced every 3 wk into a continuous flow barn that was seeded with multiple diseases. In this environment, disease resilience traits, including growth, treatment, and mortality rates, were recorded on 3,136 pigs that were genotyped with a high-density marker panel. PBMCs from 882 of these pigs from 19 batches were isolated from whole blood collected prior to the disease challenge and stimulated with five mitogens: concanavalin A (ConA), phytohemagglutinin (PHA), pokeweed mitogen (PWM), lipopolysaccharide (LPS), and phorbol myristate acetate (PMA). The proliferation of cells was evaluated at 48, 72, and 96 h and compared with unstimulated samples (rest count). Heritabilities of cell proliferation were estimated using a model with batch as a fixed effect and covariates of entry age; rest count; complete blood count proportions of lymphocytes, monocytes, eosinophils, and basophils; and pen, litter, and animal genetics as random effects. Heritability estimates were highest for response to ConA (0.30 ± 0.09, 0.28 ± 0.10, 0.17 ± 0.10, and 0.25 ±0.10 at 48, 72, and 96 h after stimulation and for area under the curve across the three time points, respectively). Estimates were in a similar range for response to PHA and PMA but low for PWM and LPS. Responses to ConA, PHA, and PMA were moderately genetically correlated with several disease resilience traits and in the expected direction, but individual estimates were not significantly different from zero due to large SEs. In conclusion, although validation is needed, MSAss, in particular based on ConA, show promise as genetic indicator traits for disease resilience. 相似文献
237.
Mike McCawley 《The Journal of small animal practice》1997,38(8):368-368
238.
Using bioinformatics to analyse germplasm collections 总被引:1,自引:0,他引:1
In the last few years, we have seen a growing emphasis on the characterisation of germplasm collections by molecular markers
such as microsatellites, AFLPs, SSAPs, RBIPs and SNPs. This emphasis has served to enhance the use of germplasm collections
in crop improvement via plant breeding while also aiding the management of collections themselves through an improved understanding
of the relationships between accessions and underlying patterns of diversity. With the new data sets becoming available comes
the recognition of the role that bioinformatics can play in making the most of the data. The basis of the new bioinformatics
infrastructure is databases that enable the association of passport and trait data with molecular markers. Visualisation tools
enable us to view large quantities of these data simultaneously and to tease out patterns underlying our data sets. We also
need analytical tools to help us search for trait-marker or haplotype-marker associations and to look for patterns of genetic
diversity. Most importantly, all of these components should interact in a fluid and intuitive manner such that the developers
of germplasm collections and the plant genetics and breeding communities can access and manipulate the data. Here, we focus
on the development of new bioinformatics tools for germplasm analysis within two projects: GENE-MINE and GERMINATE. We look
at different aspects of our bioinformatics infrastructure, to give a sense of the powerful analyses that bioinformatics can
facilitate. Finally, we look forward to bringing together these different areas to the benefit of the plant breeding and genetic
resources communities.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
239.
Kris Broos Lynne M. Macdonald Michael St. J. Warne Mary B. Barnes Mike J. McLaughlin 《Soil biology & biochemistry》2007,39(10):2693-2695
The size of the soil microbial biomass carbon (SMBC) has been proposed as a sensitive indicator for measuring the adverse effects of contaminants on the soil microbial community. In this study of Australian agricultural systems, we demonstrated that field variability of SMBC measured using the fumigation-extraction procedure limited its use as a robust ecotoxicological endpoint. The SMBC varied up to 4-fold across control samples collected from a single field site, due to small-scale spatial heterogeneity in the soil physicochemical environment. Power analysis revealed that large numbers of replicates (3-93) were required to identify 20% or 50% decreases in the size of the SMBC of contaminated soil samples relative to their uncontaminated control samples at the 0.05% level of statistical significance. We question the value of the routine measurement of SMBC as an ecotoxicological endpoint at the field scale, and suggest more robust and predictive microbiological indicators. 相似文献
240.
Toshinobu?MorikawaEmail author J.?Mike?Leggett 《Genetic Resources and Crop Evolution》2005,52(4):363-370
A new wild tetraploid oat Avena agadiriana Baum et Fedak was collected from the five populations along the Atlantic coast
in Morocco. Variations in six enzyme systems were surveyed and allele frequency, percentage of polymorphic loci, number of
alleles per locus, observed and expected heterozygosities, and unbiased genetic distance were calculated. Phenotypic frequencies
were scored representing 11 polymorphic loci. The mean percentage of polymorphic loci was 46.25, the mean number of alleles
per locus was 1.502, and the mean expected heterozygosity was 0.1526. Two heterozygotes resulting from outcrosses were found
in the progeny from M60 and M71. The population of M71 had peculiar alleles Est-4A not present in the other populations. Most
of the genetic diversity of this species was between populations with little existing within populations. Geographic and genetic
distances between populations were positively correlated with each other and the correlation coefficient was 0.7031. Cluster
analysis showed two strongly differentiated groups were apparent, M71 and M74, and the remainder. The former group appears
to be adapted to man-made habitat, such as road side or eucalyptus plantation, and the latter to a distinct dry, sandy habitat.
To make wide intra-specific variation in this species, the modified mating system would be indispensable. 相似文献