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101.
Nicola Gladden Hayley Haining Livia Henderson Francesco Marchesi Libby Graham Michael McDonald Fraser. R. Murdoch Anna Bruguera Sala Jayne Orr Kathryn Ellis 《Irish veterinary journal》2015,69(1):1
Background and case presentation
A three year old, second lactation Holstein dairy cow presented to the Scottish Centre for Production Animal Health and Food Safety, Glasgow University Veterinary School in November 2014 with a history of post-calving vulval/vaginal bleeding nine days prior to presentation, followed by a sudden reduction in milk yield. Subsequent investigations resulted in a diagnosis of immune-mediated haemolytic anaemia secondary to infection with Mycoplasma wenyonii.Conclusion
This report of a novel presentation of Mycoplasma wenyonii in a dairy cow illustrates the need to consider M.wenyonii as a potential differential diagnosis when a cow presents with anaemia and will discuss the potential implications of the condition at herd-level.102.
R. H. Johansen B. Farnsworth D. C. Nelson G. A. Secor N. Gudmestad P. H. Orr A. A. Boe 《American Journal of Potato Research》1986,63(12):701-707
NorKing Russet is an oblong to slightly blocky, russet-skinned potato cultivar with medium-early maturity and a strong vine. It has resistance to verticillium wilt but is susceptible to most viruses and to early and late blight. It is generally medium to high yielding and high in total solids. 相似文献
103.
P. H. Orr R. B. Toma S. T. Munson B. D’Appolonia 《American Journal of Potato Research》1982,59(12):605-611
Breads prepared from 5, 10, and 15% potato peel/white flour, 30% whole wheat flour, and 100% white flour plus two commercial, high fiber, dark breads in fresh and frozen/defrosted forms were evaluated sensorially by both untrained and trained panels. It appears that potato peel can be included in bread for the purpose of increasing dietary fiber without unduly sacrificing quality and acceptability. However, a musty aroma in the breads containing peel possibly influenced their flavor and overall rating scores, roughly in proportion to the amount of peel they contained. 相似文献
104.
F. Lauer J. C. Miller N. Andersen E. Banttari A. Kallio S. Munson P. Orr D. Preston D. G. Smallwood J. Sowokinos G. Titrud R. Wenkel J. Wiersma D. Wildung 《American Journal of Potato Research》1988,65(7):387-391
Krantz is an oblong to slightly blocky, russet-skinned potato cultivar with medium-late maturity and a vigorous vine. It is resistant to hollow heart, has high resistance to common scab and possesses high field resistance to late blight. It is moderately resistant toVerticillium wilt, susceptible to early blight, viruses S and X, and exhibits symptoms of bacterial ring rot. Krantz is adapted to the irrigated sands, but will growth crack in heavier soils. 相似文献
105.
Land and water interface zones 总被引:1,自引:0,他引:1
John P. Downing Michel Meybeck James C. Orr R. R. Twilley H. W. Scharpenseel 《Water, air, and soil pollution》1993,70(1-4):123-137
This paper reports analyses of C pools and fluxes in land-water interface zones completed at the International Workshop: Terrestrial Biospheric Carbon Fluxes; Quantification of Sinks and Sources of CO2 (Bad Harzburg, Germany, March 1–5, 1993). The objective was to determine the role of these zones as global sinks of atmospheric CO2 as part of a larger effort to quantify global C sinks and sources in the past (ca. 1850), the present, and the foreseeable future (ca. 2050). Assuming the world population doubles by the year 2050, storage of atmospheric C in reservoirs will also double, as will river loads of atmospheric C and nutrients. It is estimated that C sinks in temperate and boreal wetlands have decreased by about 50%, from 0.2 to 0.1 Gt C yr?1 since 1850. The total decrease for wetlands may be considerably larger when tropical wetlands are taken into account, however, the area and C density of tropical wetlands are not well known at this time. Changes in cultivation practices and improved sampling of methaneogenesis have caused estimates of CH4 emissions from ricelands to drop substantially from 150 to 60 Tg yr?1. Even with doubled N and P loads, rivers are unlikely to fertilize more than about 20% of the new primary production in the coastal ocean. The source of C for this new production may not be the atmosphere, however, because the coastal ocean exchanges large quantities of DIC with the open ocean. Until the C fluxes from air-sea exchange of CO2 and DIC are better quantified, the C-sink potential of the coastal ocean will remain a major uncertainty in the global C cycle. Analysis of model simulations of oceanic C uptake reconfirmed that the open ocean appears to take up about 2.0 Gt C yr?1 from the atmosphere and that model estimates are in better accord now, ±0.5 Gt C yr?1, than ever before. Land use management must consider the unique C sinks in coastal and alluvial wetlands in order to minimize the future negative impacts of agriculture and urban development. Long-term monitoring will be essential to prove the success, or failure, of management practices to sustain wetlands in the future. Relative to the other systems examined at the workshop, the C-sink capacity of the ocean (excluding estuaries) is not likely to be measurably affected in the foreseeable future by the management scenarios considered at the workshop. 相似文献
106.
J. R. Sowokinos P. H. Orr J. A. Knoper J. L. Varns 《American Journal of Potato Research》1987,64(5):213-226
Mechanical handling of Norchip (cv.) potatoes resulted in sucrose concentrations that exceeded 1% (fresh wt basis) 10 days after treatment. More than 65% of the maximal sugar accumulation occurred within 5 days of handling. Potatoes increased in their ability to produce sucrose as storagetime increased. Sucrose accumulation in response to handling stress was not mediated via gross physical disruption of the amyloplast membrane. Electron micrographs indicated that starch granules of both handled and control potatoes were surrounded by intact and continuous plastid (amyloplast) membranes throughout the major portion (1 to 8 months) of the storage season (8.9 C). Glucose levels did not increase at a similar rate compared to changes in sucrose concentration. Results suggest that the majority of the sucrose, which occurred during storage and/or handling stress, was not efficiently converted to reducing sugars via the enzyme invertase. Sucrose and glucose concentrations in all potatoes began to increase and chip color darkened as tubers senesced (9 to 10 months storage). Examination of electron micrographs during this storage period revealed that the bi-layers of the amyloplast membrane were separating. The mechanical handling of senescing potatoes (10 months in storage) resulted in a shift of the plastid membrane to a more disrupted state over that noted in the control. The variation in chip color induced by handling and/or storage time in Norchip potatoes was closely associated with the variation in glucose content (r = 0.953). 相似文献
107.
Tests were conducted by the Agricultural Engineering Staff at North Dakota State University, Fargo, North Dakota, during the summer of 1970 to evaluate the production of carbon monoxide gas due to internal combustion engine operation in warehouses. Tests compared gasoline engines and LP gas engines, equipped with regular and catalytic mufflers and with the fuel system at normal and 10% rich air-fuel ratios. The engines were operated on a cycle of load and no load conditions to approximate actual usage. Exhaust gases were piped to a 10,000 cubic foot sealed room and intake air was taken from the same room. Gas from the test room was sampled periodically and analyzed for carbon monoxide and other gases. A method was devised to estimate the probable CO levels in a warehouse, knowing the volume and infiltration rate of the warehouse and the specific engine being used in the warehouse. For the test conditions:
- The LP gas engine produced 50% less CO than the gasoline engine.
- The catalytic muffler reduced CO by 40% when compared with a conventional muffler.
- Engines set at normal A-F ratios produced 42% less CO than engines set 10% rich.
108.
Measurement of potato chip color is extremely important to the potato processing industry. A procedure is described whereby finished chip samples were utilized for correlation of one spectrophotometric chip color measurement system with another. Calibration, standardization, sample preparation, randomization and prediction equation development procedures are described. 相似文献
109.
Intake characteristics of perennial ryegrass varieties when grazed by yearling beef cattle under rotational grazing management 总被引:1,自引:0,他引:1
R. J. Orr J. E. Cook K. L. Young R. A. Champion S. M. Rutter 《Grass and Forage Science》2005,60(2):157-167
Four intermediate‐heading perennial ryegrass (Lolium perenne L.) varieties, which in previous studies had been associated with high‐ or low‐intake characteristics when swards containing them had been continuously stocked with sheep, were sown as monocultures. They were rotationally grazed, using 1‐d paddocks, with core groups of four yearling Simmental × Holstein beef heifers in 2002 and 2003 and ingestive and ruminative behaviour, and sward factors, were measured. There were two diploid (Belramo and Glen) and one tetraploid (Rosalin) perennial ryegrass varieties and one tetraploid hybrid (Lolium × boucheanum Kunth) (AberExcel) variety. Intake rate (IR) was significantly higher in August 2003 for heifers grazing Glen than those grazing Belramo [27·5 vs. 20·6 g dry matter (DM) min?1; P = 0·019], but there were no significant differences between varieties in two other measurement periods. This is in contrast to previous results with sheep when IR were significantly higher for Glen than Belramo and for AberExcel than Rosalin. Total jaw movement rates during grazing were significantly higher for heifers on the tetraploid swards than those on the diploid swards (87·7 vs. 83·6 jaw movements min?1; P = 0·023) in September 2002. Ruminating time was significantly lower for heifers on the tetraploid swards than those on the diploid swards (453 vs. 519 min 24 h?1; P = 0·012) in July 2002. Digestibility of grass snips was significantly higher on the tetraploid than the diploid swards [697 vs. 680 g digestible organic matter (DOM) kg?1 DM; P = 0·042] in September 2003 and, within diploids, was significantly higher for Glen than Belramo (696 vs. 663 g DOM kg?1 DM; P = 0·014). There were significant differences in sheath tube and leaf lengths and in the population density of tillers between and within ploidies, which might have been expected to have influenced intake characteristics, but this was not generally found under rotational grazing with cattle. In order to separate the effects of defoliation interval from those of grazing style of the different ruminant species, it is suggested that grass variety evaluations using continuously stocked cattle swards are required. 相似文献
110.
Porcine circovirus type 2 detection in in vitro produced porcine blastocysts after virus sperm exposure 下载免费PDF全文
Giovanna Galeati Augusta Zannoni Marcella Spinaci Diego Bucci Fabio Ostanello Serena Panarese Carlo Tamanini Giuseppe Sarli 《Animal Science Journal》2016,87(4):511-516
This study was aimed at assessing the capability of semen experimentally infected with porcine circovirus type 2 (PCV2) to produce porcine blastocysts PCR positive for PCV2. Embryos were obtained from in vitro maturation (IVM) and in vitro fertilization (IVF) of porcine oocytes or by parthenogenesis. Sperm suspension was exposed to PCV2b and utilized for IVF. PCV2 spiked semen did not reveal any reduction in sperm viability or motility but its ability to produce infected blastocysts was irrelevant as only one out of 15 blastocysts obtained by IVF were PCV2b; however two blastocysts were PCV2a positive. Furthermore, the presence of PCV2 was demonstrated also in embryos obtained by parthenogenesis (one out of 17 was PCV2b and one PCV2a positive). Even if PCV2 firmly attaches to the surface of spermatozoa, experimentally spiked sperm were not effective in infecting oocytes during IVF and in producing PCR positive embryos. The infected blastocysts we obtained derived most probably from infected oocytes recovered at the abattoir. 相似文献