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31.
Methods to improve the hatchability of checked chicken eggs 总被引:3,自引:0,他引:3
1. The hatchability of checked Leghorn and broiler parent hatching eggs was significantly improved by shell treatment: smearing with synthetic adhesive resin (Fevicol), or pasting cellophane tape or insulation tape over the checked portion of the shell. 2. Shell damage reduced hatchability by increasing evaporative loss, leading to embryonic dehydration. 3. Relative chick weight, expressed as a percentage of egg weight was lower in untreated checked eggs but comparable between intact and shell-treated hatching eggs. 4. The cost of chick production can be reduced by shell treatment of checked hatching eggs, especially in broiler parent eggs. 相似文献
32.
Radhakrishnan Srinivasan Robert A. Moreau Kent D. Rausch Ronald L. Belyea M. E. Tumbleson Vijay Singh 《Cereal Chemistry》2005,82(5):528-533
A process was developed to separate fiber from distillers dried grains with solubles (DDGS) in a dry‐grind corn process. Separation of fiber from DDGS would provide two valuable coproducts: 1) DDGS with reduced fiber, increased fat, and increased protein contents; and 2) fiber. The process, called elusieve process, used two separation methods, sieving and elutriation, to separate the fiber. Material carried by air to the top of the elutriation column was called the lighter fraction and material that settled to the bottom of the column was called the heavier fraction. We evaluated the compositions of fractions produced from sieving and elutriation. Two commercial samples of DDGS were obtained from two dry‐grind corn plants. Sieving over four screens (869, 582, 447, and 234 μm openings) created five size categories. The two smallest size categories contained >40% (w/w) of the original DDGS and had reduced fiber and increased protein and fat contents relative to the original DDGS. Elutriation of the remaining three size categories increased protein and fat contents and reduced fiber contents in the heavier fractions. Elutriation at air velocities of 1.59–5.24 m/sec increased the protein content of the heavier fraction by 13–41% and increased the fat content of the heavier fraction by 4–127% compared with the bulk fractions of each size category. This process was effective in separating fiber from both DDGS samples evaluated. Elusieve process does not require changes in the existing dry‐grind process and can be implemented at the end of the dry‐grind process. 相似文献
33.
Radhakrishnan Srinivasan Vijay Singh Ronald L. Belyea Kent D. Rausch Robert A. Moreau M. E. Tumbleson 《Cereal Chemistry》2006,83(4):324-330
Separation of fiber from distillers dried grains with solubles (DDGS) provides two valuable coproducts: 1) enhanced DDGS with reduced fiber, increased fat and increased protein contents and 2) fiber. Recently, the elusieve process, a combination of sieving and elutriation was found to be effective in separating fiber from two commercial samples of DDGS (DDGS‐1 and DDGS‐2). Separation of fiber decreased the quantity of DDGS, but increased the value of DDGS by increasing protein content and produced a new coproduct with higher fiber content. Economic analysis was conducted to determine the payback period, net present value (NPV), and internal rate of return (IRR) of the elusieve process. The dependence of animal foodstuff prices on their protein content was determined. Equipment prices were obtained from industrial manufacturers. Relative to crude protein content of original DDGS, crude protein content of enhanced DDGS was higher by 8.0% for DDGS‐1 and by 6.3% for DDGS‐2. For a dry‐grind plant processing corn at the rate of 2,030 metric tonnes/day (80,000 bushels/day), increase in revenue due to the elusieve process would be $0.4 to 0.7M/year. Total capital investment for the elusieve process would be $1.4M and operating cost would be $0.1M/year. Payback period was estimated to be 2.5–4.6 years, NPV was $1.2–3.4M, and IRR was 20.5–39.5%. 相似文献
34.
Xenon extracted from natural iodyrite (silver iodide) from Broken Hill, New South Wales, Australia, contains excess xenon-129 from the in situ decay of naturally occurring iodine-129 and excess xenon-128 from neutron capture on iodine-127. On the basis of the amount of radiogenic xenon-129, it is estimated that, prior to the nuclear age, terrestrial iodine contained an equilibrium ratio of iodine-129 to iodine-127 of between 3.3 x 10(-15) and 2.2 x 10(-15). 相似文献
35.
de Gouw JA Middlebrook AM Warneke C Ahmadov R Atlas EL Bahreini R Blake DR Brock CA Brioude J Fahey DW Fehsenfeld FC Holloway JS Le Henaff M Lueb RA McKeen SA Meagher JF Murphy DM Paris C Parrish DD Perring AE Pollack IB Ravishankara AR Robinson AL Ryerson TB Schwarz JP Spackman JR Srinivasan A Watts LA 《Science (New York, N.Y.)》2011,331(6022):1295-1299
A large fraction of atmospheric aerosols are derived from organic compounds with various volatilities. A National Oceanic and Atmospheric Administration (NOAA) WP-3D research aircraft made airborne measurements of the gaseous and aerosol composition of air over the Deepwater Horizon (DWH) oil spill in the Gulf of Mexico that occurred from April to August 2010. A narrow plume of hydrocarbons was observed downwind of DWH that is attributed to the evaporation of fresh oil on the sea surface. A much wider plume with high concentrations of organic aerosol (>25 micrograms per cubic meter) was attributed to the formation of secondary organic aerosol (SOA) from unmeasured, less volatile hydrocarbons that were emitted from a wider area around DWH. These observations provide direct and compelling evidence for the importance of formation of SOA from less volatile hydrocarbons. 相似文献
36.
Eucrites are a group of meteorites that represent the first planetary igneous activity following metal-silicate differentiation on an early planetesimal, similar to Asteroid 4 Vesta, and, thus, help date geophysical processes occurring on such bodies in the early solar system. Using the short-lived radionuclide (182)Hf as a relative chronometer, we demonstrate that eucrite zircon crystallized quickly within 6.8 million years of metal-silicate differentiation. This implies that mantle differentiation on the eucrite parent body occurred during a period when internal heat from the decay of (26)Al and (60)Fe was still available. Later metamorphism of eucrites took place at least 8.9 million years after the zircons crystallized and was likely caused by heating from impacts, or by burial under hot material excavated by impacts, rather than from lava flows. Thus, the timing of eucrite formation and of mantle differentiation is constrained. 相似文献
37.
Aromatic rices are preferred by the consumers all over the world due to its flavour and palatability. Although a large number
of these collections are available, little systematic analysis of genetic diversity has been carried out. With the objective
of identification and classification of aromatic rice genotypes, RAPD profiling was employed using 58 random decamer primers.
Most of these primers (96.5%) detected polymorphism among the genotypes. Of the 465 amplified bands, 314 were polymorphic.
Cluster analysis based on Jaccard's similarity coefficient using UPGMA grouped all the traditional tall, photosensitive, low
yielding, long grained ‘basmati’ aromatics together. The short grained aromatic cultivars, formed a different cluster with
high level of average similarity among themselves. The dendrogram based on 58 primers was highly similar to that based on
10 and 15 primers with matrix correlation (r) of 0.88 and 0.91, respectively. This suggested that a set of 10 primers can
be employed for an initial assessment of genetic diversity in a large number of collections. All the rice genotypes included
in the study could be distinguished from each other at the level of 19 to 186 polymorphic bands between individuals in pair
wise comparison over all the 58 primers. Probability of identical profiles by chance suggested that about 1041 genotypes can be unambiguously differentiated by RAPD fingerprints obtained by 58 primers. A diagrammatic mode of presentation
of DNA fingerprints of the aromatic rices based on 10 of the informative primers was developed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
38.
39.
Srinivasan V Gillespie BE Lewis MJ Nguyen LT Headrick SI Schukken YH Oliver SP 《Veterinary microbiology》2007,124(3-4):319-328
Pulsed field gel electrophoresis (PFGE) patterns, susceptibility to 26 antimicrobial agents used in veterinary and human medicine, and prevalence of antimicrobial resistance genes of Escherichia coli isolated from cows with mastitis were evaluated. Among 135 E. coli isolates, PFGE analysis revealed 85 different genetic patterns. All E. coli were resistant to two or more antimicrobials in different combinations. Most E. coli were resistant to antimicrobials used in veterinary medicine including ampicillin (98.4%, >or=32 microg/ml) and many E. coli were resistant to streptomycin (40.3%, >or=64 microg/ml), sulfisoxazole (34.1%, >or=512 microg/ml), and tetracycline (24.8%, >or=16 microg/ml). Most E. coli were resistant to antimicrobials used in human medicine including aztreonam (97.7%, >or=32 microg/ml) and cefaclor (89.9%, >or=32 microg/ml). Some E. coli were resistant to nitrofurantoin (38%, >or=128 microg/ml), cefuroxime (22.5%, >or=32 microg/ml), fosfomycin (17.8%, >or=256 microg/ml). All E. coli were susceptible to ciprofloxacin and cinoxacin. Almost 97% (123 of 127) of ampicillin-resistant isolates carried ampC. Eleven of 52 (21.2%) streptomycin-resistant isolates carried strA, strB and aadA together and 29 streptomycin-resistant isolates (55.8%) carried aadA alone. Among 44 sulfisoxazole-resistant E. coli, 1 isolate (2.3%) carried both sulI and sulII, 12 (27.3%) carried sulI and 10 (22.7%) isolates carried sulII. Among 32 tetracycline-resistant isolates, 14 (43.8%) carried both tetA and tetC and 14 (43.8%) carried tetC. Results of this study demonstrated that E. coli from cows with mastitis were genotypically different, multidrug resistant and carried multiple resistance genes. These bacteria can be a reservoir for antimicrobial resistance genes and can play a role in the dissemination of antimicrobial resistance genes to other pathogenic and commensal bacteria in the dairy farm environment. 相似文献
40.
Griffin CT Srinivasan Y Zheng YW Huang W Coughlin SR 《Science (New York, N.Y.)》2001,293(5535):1666-1670
The coagulation protease thrombin triggers fibrin formation, platelet activation, and other cellular responses at sites of tissue injury. We report a role for PAR1, a protease-activated G protein-coupled receptor for thrombin, in embryonic development. Approximately half of Par1-/- mouse embryos died at midgestation with bleeding from multiple sites. PAR1 is expressed in endothelial cells, and a PAR1 transgene driven by an endothelial-specific promoter prevented death of Par1-/- embryos. Our results suggest that the coagulation cascade and PAR1 modulate endothelial cell function in developing blood vessels and that thrombin's actions on endothelial cells-rather than on platelets, mesenchymal cells, or fibrinogen-contribute to vascular development and hemostasis in the mouse embryo. 相似文献