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101.
Immunisation against ovine caseous lymphadenitis: comparison of Corynebacterium pseudotuberculosis vaccines with and without bacterial cells 总被引:2,自引:0,他引:2
Sheep were immunised with Corynebacterium pseudotuberculosis vaccines prepared from cell-free toxoid or from toxoid with formalin-killed cells of C pseudotuberculosis added. Resistance of sheep to infection was tested 6 months after immunisation by inoculation with caseous lymphadenitis pus. The outcome was assessed 3 months later by slaughter and inspection of the sheep for lesions of caseous lymphadenitis. immunised sheep were adequately protected against infection as shown by a significant reduction in the number of sheep exhibiting lesions compared with control sheep, and by fewer abscesses in affected vaccinated sheep than in affected control sheep. The protective potency of the vaccines was not improved by the inclusion of cells of C pseudotuberculosis. 相似文献
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Seven cases of idiopathic Horner's Syndrome in the Collie are described. Five males and two females presented with unilateral miosis, ptosis of the upper eyelid, enophthalmos and protrusion of the third eyelid. Thorough examination, pharmacological testing with phenylephrine, complete blood counts and radiography of the tympanic bullae and thorax were performed. The etiology was not identified in any of the cases. Clinical signs improved with pharmacologic testing within 20–40 min. In five dogs, total resolution of clinical signs was observed at 4 and 16 weeks after their initial appearance. Pharmacological testing suggested that the deficit could be at the preganglionic neuron. 相似文献
105.
Marcelino Herrera Ismael Hachero Montserrat Rosano José Francisco Ferrer José Manuel Márquez José Ignacio Navas 《Aquaculture International》2008,16(1):69-84
The wedge sole is a target species in the fisheries of the Gulf of Cadiz (Spain). Having reared them to commercial size, we
have studied reproduction and breeding in captivity of the wedge sole in this work here. The breeders adapt easily to captivity,
and they can spawn in less than 1 year in captivity. The relative fecundity is relatively high, 1.06–2.33 · 106 eggs kg−1 per spawning season (mean 1.6 ± 0.1). Larval SGR is high, 7.2 ± 0.2% day−1 (range 5.8–9.1), similar to other cultured flatfish species. In 1 year, some individuals reach market size and can release
eggs, registering SGRs of 1.39–1.66% day−1 (mean 1.56 ± 0.01). This species presents some very different characteristics with respect to other farmed flatfishes (turbot,
halibut and Senegal sole, mainly), so that it is necessary to develop new techniques to optimise its cultivation. In the present
work, the first results are presented on the biology of the wedge sole in captivity. 相似文献
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108.
Maciorowski KG Herrera P Jones FT Pillai SD Ricke SC 《Veterinary research communications》2006,30(2):127-137
Food-borne salmonellosis continues to be a major public health concern, and contamination with Salmonella spp. in pre-harvest animal production is considered a primary contributor to this problem. Animal feeds can easily become
contaminated during primary production, feed mixing and processing as well as during feeding. Consequently, monitoring and
surveillance of feeds and feed ingredients for Salmonella spp. contamination may be useful or necessary in the prevention and control of this organism. Cultural and immunological
detection methods for salmonellae have been used or suggested as possible approaches for use in animal feeds. Cultural methods
remain advantageous owing to their ability to detect viable bacterial cells, while immunological methods have the capability
of detecting nonculturable bacterial cells. Advancements and improvements in both methodologies offer opportunities for eventual
routine use of these detection technologies in animal feed assays. 相似文献
109.
Weaver JC Milliron GW Miserez A Evans-Lutterodt K Herrera S Gallana I Mershon WJ Swanson B Zavattieri P DiMasi E Kisailus D 《Science (New York, N.Y.)》2012,336(6086):1275-1280
Nature has evolved efficient strategies to synthesize complex mineralized structures that exhibit exceptional damage tolerance. One such example is found in the hypermineralized hammer-like dactyl clubs of the stomatopods, a group of highly aggressive marine crustaceans. The dactyl clubs from one species, Odontodactylus scyllarus, exhibit an impressive set of characteristics adapted for surviving high-velocity impacts on the heavily mineralized prey on which they feed. Consisting of a multiphase composite of oriented crystalline hydroxyapatite and amorphous calcium phosphate and carbonate, in conjunction with a highly expanded helicoidal organization of the fibrillar chitinous organic matrix, these structures display several effective lines of defense against catastrophic failure during repetitive high-energy loading events. 相似文献
110.
Kolb N Herrera JL Ferreyra DJ Uliana RF 《Journal of agricultural and food chemistry》2001,49(10):4538-4541
An improved analytical method was developed which may be applied to quality control of stevioside and rebaudioside A contents in dried leaves of Stevia rebaudiana before processing; in a selective sampling program searching for plants of higher yield in diterpene glycosides content; or when a large number of samples are sent to the laboratory for analysis. The procedure developed involves two steps: solvent extraction followed by an isocratic HPLC analysis. The sample, 1 g of dried leaves of S. rebaudiana, is ground and solvent-extracted with EtOH 70% (w/w) in Erlenmeyer flasks by shaking for 30 min in a 70 degrees C water bath. After the extract was cooled, it was filtered and analyzed by HPLC using an NH(2) column (250 x 4.6 mm) and a mixture of acetonitrile/water (80:20, v/v) as mobile phase, pH 5 adjusted with acetic acid. The detection was in the UV range at 210 nm (0.04 AUFS). Quantitation was performed by means of an external standard calibration curve for each analyte which had been obtained from standard solutions of pure stevioside and rebaudioside A. Working under these conditions there were no observed interference effects. The method saves time in sample preparation, and reduces sample handling and chromatographic analysis time, while having little loss of precision [coefficient of variation (CV%) between 1.8% and 3.0%] and recovery [between 98.5% and 100.5%]. The method was applied to 30 samples of S. rebaudiana from Misiones (Northeastern Argentina), and the stevioside content found ranged between 3.78 and 9.75% (weight) whereas Rebaudioside A content ranged between 1.62 and 7.27% (weight). 相似文献