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921.
L. G. Buttle A. C. Burrells J. E. Good P. D. Williams P. J. Southgate C. Burrells 《Veterinary immunology and immunopathology》2001,80(3-4)
A lectin present in soya, soybean agglutinin (SBA), was identified in electrophoretic profiles and immunoblots of dehulled solvent-extracted soybean meal (DSSM), full-fat soybean meal (FFSM) and of aqueous extracts of feeds incorporating them in their formulation. A quantitative estimation was made of the proportion of SBA comprising the total protein in FFSM and a trial diet was prepared containing an amount of pure SBA similar to that in diets incorporating high levels of the whole soya product. Fish fed with this diet exhibited similar pathological disruption of the intestinal tract to that observed in fish given a diet with a high level of DSSM (60% of the diet). Furthermore, immuno-histochemistry revealed the binding of the SBA to the enterocytes lining the intestinal villi both of fish fed a diet incorporating pure SBA and those fed a diet containing a high-level of soya (60%). Our results suggest that SBA binds in vivo to the intestinal epithelium of fish and has a contributory role in pathological changes associated with fish feeds containing high levels of soybean proteins. 相似文献
922.
A technique for continuous computerised recording and analysis of the stride of horses on a treadmill is described. Advantages of the system are low cost, the use of normal shoes and the calculation of stride parameters in real time. 相似文献
923.
924.
I. H. Williams 《Pest management science》1972,3(2):179-181
A microcoulometric method is described for the direct determination of nanogram amounts of methomyl (S-methyl-N-[(methylcarbamoyl)-oxy]thioacetimidate). An all-glass gas chromatographic system coupled to a microcoulometer with a nitrogen-specific cell was used. The column was packed with a mixture of 6% OV210 and 4% OV101 on Gas Chrom Q, as was the glass transfer tube which connected the chromatographic column to the pyrolysis furnace. Some loss occurred but response was linear from 125 to 20 ng and sensitivity was such that 20 ng of methomyl could be readily measured. 相似文献
925.
The epidemiology of adult and larval (tissue) cestodes in dyfed (U.K.). 1. The cestodes of farm dogs
B.M. Williams 《Veterinary parasitology》1976,1(3):271-276
Sixty-three per cent of dogs on 100 sheep farms and 62% of those on 18 wintering farms in Dyfed were found infected with adult cestodes. The prevalence of each species is recorded and the relationship between diet, anthelmintic treatment and cestode infection is discussed. 相似文献
926.
A computer model is presented to estimate the quantitative impact of future research/extension activities in various aspects of swine production on the profit of an average swine producer in Hawaii. The model was designed and used to generate information for making decisions regarding funding of future research/extension projects in the swine production area. The computer model has two components. The first simulates the biological production behaviour of a typical pig enterprise of Hawaii. The General Purpose Simulation System (GPSS) language was used to model the stochastic nature of the production. For a given set of biological parameters, this component provides annual production levels, feed consumption and statistics for selecting the capacity of various building facilities. The second component computes annual revenues, costs and rate of return to capital investment over the analysis period by using discounted cash flow method. In addition to other cost and price data, it uses the output of the first component as input. 相似文献
927.
928.
H. Williams Smith 《Veterinary research communications》1977,1(1):213-224
Several characters ofEscherichia coli enteropathogenic for farm animals and man are determined by transmissible plasmids. These include the production of K88 and K99 antigens, enterotoxin and haemolysin. The construction of bacteria of a desired plasmid composition provides an elegant method of obtaining information on these characters. Such studies have revealed that the K88 antigen is importantly involved in the ability of enteropathogenicE. coli to proliferate in the small intestine of piglets and that the K99 antigen performs a similar function inE. coli enteropathogenic for calves and lambs. Enterotoxin is mainly responsible for the diarrhoea that then ensues.
Kurzfassung Mehrere pathogene Eigenschaften der E. coli für Mensch und Haustier werden durch übertragbare Plasmiden bestimmt. Dazu gehört auch die Produktion von K88 und K99 Antigenen, von Enterotoxinen und Hämolysin. Die Entwicklung von Bakterien mit der gewünschten Plasmazusammensetzung stellt eine gute Methode dar, Information über diese Eigenschaften zu gewinnen. Untersuchungen dieser Art haben gezeigt, dass K88 Antigene die Vermehrung von E. coli im Dünndarm von jungen Schweinen, fördert, und dass K99 Antigene eine ähnliche Wirkung auf die enteropathogenen E. coli bei Kälbern und Lämmern haben. Enterotoxin ist die Hauptursache für die dabei auftretende Diarrhoea.
Resume Plusieurs caracteres d'Escherichia coli enteropathogenes pour les animaux de ferme et l'homme sont determines par des plasmides transmissibles. Ceux-ci incluent la production d'antigenes K88 et K99, d'enterotoxine et d'hemolysine. Un modile de bacterie ayant la composition plasmidique desiree fournit une methode elegante pour l'obtention d'une information sur ces caracteres. De telles etudes ont montre que l'antigene K88 intervient de facon marquee dans l'aptitude d'E. coli enteropathogene a proliferer dans l'intestin grole de porcelets et que l'antigene K99 a une fonction similaire pourE. coli enteropathogene des veaux et des agneaux. L'enterotoxine a une respourabilite majeure dans la diarrhee.
Riassunto Alcuni caratteri dell'E. coli patogeno per l'uomo e per gli animali domestici sono determinati da plasmidi transmissibili. Questi comprendono la produzione di antigeni K88 e K99, di enterotossina e di emolisina. Un modello di batteri della composizione plasmidica desiderata fornisce un metodo ideale per l'ottenimento di informazioni su questi caratteri. Tali studi hanno dimostrato che l'antigene K88 svolge un ruolo importante nella proliferazione dell'E. coli enteropatogeno nell'intestino tenue dei porcellini e che l'antigene K99 svolge una funzione simile per l'E. coli enteropatogeno dei vitelli e degli agnelli. L'enterotossina e il maggior responsbile della diarrea che ne consegue.相似文献
929.
Enzyme-linked immunosorbent assay for detecting antibodies to Brucella abortus in bovine milk and serum 总被引:1,自引:0,他引:1
F C Heck J D Williams J Pruett R Sanders D L Zink 《American journal of veterinary research》1980,41(12):2082-2084
An enzyme-linked immunosorbent assay (ELISA) method was evaluated for the detection of antibodies to Brucella abortus in cows milk. Milk samples from seropositive or -negative cows were sed to determine the distribution of absorbance values to classify milk as ELISA positive or ELISA negative. Brucella abortus was isolated from milk samples from 10 (45%) of the 22 cows whose milk and serum were ELISA positive. The ELISA was evaluated and determined to be an appropriate method for detecting antibodies to B abortus in bovine milk. 相似文献
930.
A method is described for the gas chromatographic determination of residues of isofenphos (BAY 92114, O-ethyl O-2-isopropoxycarbonylphenyl isopropylphosphor-amidothioate) and its phosphoramidate which is a potential metabolite. When potato, cabbage, rapeseed and a sandy loam soil were fortified with 0.01, 0.1 and 1.0 mg/kg and analysed by the method described, the recoveries ranged from 76 to 98%. The limits of detection of the method were 0.5 and 1.0 ng for isofenphos and isofenphos oxygen analogue respectively. Degradation under field conditions of isofenphos to its oxygen analogue was demonstrated in a sample of field-treated potatoes. 相似文献