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61.
Neil A. Bryant Adam S. Rash Alana L. Woodward Elizabeth Medcalf Maud Helwegen Franziska Wohlfender Fatima Cruz Claudia Herrmann Kerstin Borchers Ashish Tiwari Thomas M. Chambers J. Richard Newton Jennifer A. Mumford Debra M. Elton 《Veterinary microbiology》2011,147(1-2):19-27
Like other influenza A viruses, equine influenza virus undergoes antigenic drift. It is therefore essential that surveillance is carried out to ensure that recommended strains for inclusion in vaccines are kept up to date. Here we report antigenic and genetic characterisation carried out on equine influenza virus strains isolated in North America and Europe over a 2-year period from 2008 to 2009. Nasopharyngeal swabs were taken from equines showing acute clinical signs and submitted to diagnostic laboratories for testing and virus isolation in eggs. The sequence of the HA1 portion of the viral haemagglutinin was determined for each strain. Where possible, sequence was determined directly from swab material as well as from virus isolated in eggs. In Europe, 20 viruses were isolated from 15 sporadic outbreaks and 5 viruses were isolated from North America. All of the European and North American viruses were characterised as members of the Florida sublineage, with similarity to A/eq/Lincolnshire/1/07 (clade 1) or A/eq/Richmond/1/07 (clade 2). Antigenic characterisation by haemagglutination inhibition assay indicated that the two clades could be readily distinguished and there were also at least seven amino acid differences between them. The selection of vaccine strains for 2010 by the expert surveillance panel have taken these differences into account and it is now recommended that representatives of both Florida clade 1 and clade 2 are included in vaccines. 相似文献
62.
M Boller K Kelers MA Stevenson KD Winkel S Hardjo J Heller PR Judge HM Ong AM Padula C Reddrop LCP Santos CR Sharp L Smart KL Swindells D Tabrett JR Wierenga 《Australian veterinary journal》2020,98(9):442-448
SnakeMap is a national cloud-based, veterinary snakebite registry. It was designed to prospectively collect data of the clinical circumstances and temporospatial information on cases of snake envenomation in dogs and cats. We herein introduce the project and summarise the data from the first 4 years of SnakeMap. The registry is a veterinary community-based online database allowing case entry from veterinary hospitals across Australia. Registry data comprise hospital characteristics, patient characteristics, envenoming snake type, treatment and outcome variables, including time and geolocation of the snake bite. We present summative information on select key variables from the SnakeMap registry (1 July 2015 to 30 June 2019). Twenty-eight hospitals from 6 states/territories entered 624 cases into the registry, including 419 dogs (67%) and 205 cats (33%). Bite time was available in 216 animals of which 90 (42%) were reported to be bitten in the 3 hours between 03:00 pm and 05:59 pm; median bite to presentation interval was 60 (interquartile range [IQR] 30, 211) minutes in dogs and 95 (IQR 41, 238) minutes in cats. Bites occurred in the owner's yard in 356 dogs (85%) and 53 cats (26%). A snake venom detection kit was used in 172 cases (28%) and antivenom was administered in 523 cases (85%). Most animals (n = 534, 88%) survived to discharge (median hospitalisation of 25 [IQR 16, 62] hours). SnakeMap effectively collects relevant clinical data from dogs and cats with presumed snake bite and provides locally specific information on the epidemiology of snake envenomation in small animals. 相似文献
63.
W.D. Pew J.L. Abbott Bryant R. Gardner T.C. Tucker 《Journal of plant nutrition》2013,36(12):1701-1713
Cabbage (Brassica olearacea var. capitata L.) yield differences from added P were highly significant up to the predicted response level of 0.4 mg 1 . The increases in yield were basically due to larger head sizes. No statistical differences were found after the soil P levels were adjusted above 0.4 ppm, as determined by P isotherms constructed from initial soil samples. Slight differences occurred between years, but likely were due to cultivar growth differences. Data show that the isotherm predicted level fits rather closely the P requirements for cabbage as related to crop yields. Since extraction methods measure only the intensity factor of P, these methods could lead to incorrect P fertilization recommendations. The absorption of P is progressively reduced as the temperature goes down. 相似文献
64.
65.
66.
Bryant RJ Rao DR Ogutu S 《Plant foods for human nutrition (Dordrecht, Netherlands)》2003,58(3):213-223
Thirty-three peanut cultivars were examined for their alpha-1,6 and beta-1,4 galactosidase activities and oligosaccharide contents along with proximate compositions. The average moisture, protein, fat, ash, and carbohydrate contents were: 4.9%, 26.6%, 43.1%, 2.3% and 23.1%, respectively. The corresponding coefficients of variation were: 5.2%, 10.1%, 7.2%, 7.8% and 15.7%, respectively. Raffinose and stachyose contents (%) ranged from 0.05 to 0.12 and 0.31 to 0.61, respectively. The specific activity (micromol product/min/mg protein) of crude preparation of alpha-galactosidase for the 33 cultivars ranged from 1.096 to 2.784 for the non-germinated seeds and from not being detected in some samples up to 2.432 for the germinated seeds; the mean values for non-germinated and germinated seeds were: 1.781 and 1.410, respectively. The specific activity of beta-galactosidase ranged from 0.101 to 1.727 in the non-germinated seeds and from not being detected in some samples up to 0.898 in the germinated seeds. Germination decreased the activity of both galactosidases significantly (p < or = 0.05). 相似文献
67.
Earlier models of plant-herbivore interactions relied on forms of functional response that related rates of ingestion by herbivores
to mechanical or physical attributes such as bite size and rate. These models fail to predict a growing number of findings
that implicate chemical toxins as important determinants of plant-herbivore dynamics. Specifically, considerable evidence
suggests that toxins set upper limits on food intake for many species of herbivorous vertebrates. Herbivores feeding on toxin-containing
plants must avoid saturating their detoxification systems, which often occurs before ingestion rates are limited by mechanical
handling of food items. In light of the importance of plant toxins, a new approach is needed to link herbivores to their food
base. We discuss necessary features of such an approach, note recent advances in herbivore functional response models that
incorporate effects of plant toxins, and mention predictions that are consistent with observations in natural systems. Future
ecological studies will need to address explicitly the importance of plant toxins in shaping plant and herbivore communities. 相似文献
68.
69.
R. S. Barwick H. O. Mohammed M. E. White R. B. Bryant 《Biology and Fertility of Soils》2000,31(5):385-390
The flotation procedure for the detection of Cryptosporidium parvum and Cryptosporidium muris oocysts in feces was adapted for use on soil samples. Soil samples were seeded with known amounts of purified C. parvum or C. muris oocysts and Cryptosporidium spp.-free bovine feces. The limit of detection for this procedure was determined at different levels of inoculation for each
species. At each level of inoculation, 30 control samples were processed and the observer was blind to the status of the sample.
All samples were examined for the presence of Cryptosporidium spp. oocysts using phase-contrast microscopy. The samples were seeded with the following estimated counts of C. parvum oocysts: 1000/g, 1250/g, and 1500/g. These levels had sensitivities of 88%, 90%, and 93%, respectively. All inoculation levels
had a specificity of 100%. Thirty additional samples were inoculated with C. muris and the limit of detection was found to be 76 oocysts/g sample, with a sensitivity of 97% and a specificity of 100%.
Received: 4 October 1999 相似文献
70.
P. A. Counce R. J. Bryant C. J. Bergman R. C. Bautista Y.‐J. Wang T. J. Siebenmorgen K. A. K. Moldenhauer J.‐F. C. Meullenet 《Cereal Chemistry》2005,82(6):645-648
Important rice grain quality characteristics such as percentage of chalky rice kernels are affected by both high and low night temperatures and by different day and day/night temperature combinations. High nighttime temperatures have also been suspected of reducing rice milling quality including head rice yields. Experiments to confirm or refute this have not been reported. A controlled climate experiment was conducted. Conditions in the chambers were identical except between 2400 and 0500 hours (midnight and 5 am). For those times, two temperature treatments were imposed: 1) 18°C (low temperature treatment) and 2) 24°C (high temperature treatment). Two cultivars were tested: LaGrue and Cypress. The high temperature treatment reduced head rice yields compared with the low temperature treatment. Grain widths were reduced for the high temperature treatment compared with the low temperature treatment. There was no effect of temperature on grain length or thickness. Amylopectin chain lengths 13–24 were increased by the high temperature treatment by ≈1%. Future research will focus on determining whether genetic variability exists among cultivars in their head rice yield response to high temperatures. After identifying a source of resistance to high temperature effects, this characteristic can be incorporated into rice cultivars. In addition, ways to reduce this effect, including biotechnological remedies, have the potential for increasing rice yield and quality. 相似文献