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Avian pneumoviruses (APVs) are RNA viruses responsible for upper respiratory disease in poultry. Experimental infections are typically less severe than those observed in field cases. Previous studies with APV and Escherichia coli suggest this discrepancy is due to secondary agents. Field observations indicate APV infections are more severe with concurrent infection by Newcastle disease virus (NDV). In the current study, we examined the role of lentogenic NDV in the APV disease process. Two-week-old commercial turkey poults were infected with the Colorado strain of APV. Three days later, these poults received an additional inoculation of either NDV or E. coli. Dual infection of APV with either NDV or E. coli resulted in increased morbidity rates, with poults receiving APV/NDV having the highest morbidity rates and displaying lesions of swollen infraorbital sinuses. These lesions were not present in the single APV, NDV, or E coli groups. These results demonstrate that coinfection with APV and NDV can result in clinical signs and lesions similar to those in field outbreaks of APV. 相似文献
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Davis EG Wilkerson MJ Rush BR 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(4):404-410
The use of flow cytometry in veterinary diagnostics is becoming a valuable clinical tool with a broad range of applications. Physical characteristics of cells can be determined by the flow cytometer laser and electronics through the measurement of changes in light scatter properties. Other components and functions of cells can be defined through the application of fluorochrome dyes that have an affinity for cellular components. Traditionally, common clinical applications are immunophenotyping of cells of the hematopoietic system with fluorescent-labeled antibodies raised against specific cell surface proteins. Other approaches have been used to elucidate changes in cell function and DNA content. This review is intended to provide the reader with the fundamental uses of flow cytometry. Examples of clinical applications in equine patients include immune-mediated hemolytic anemia, immune-mediated thrombocytopenia (IMT), chronic inflammatory disease, and neoplasia. 相似文献
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Multiple, dermal and subcutaneous nodules developed in a young female Manchester Terrier dog that had a chronic history of superficial dermatophytosis. Skin biopsy specimens of the nodules revealed granulomatous inflammation in the deep dermis and subcutis with branching fungal organisms. Cultures of multiple biopsy specimens from the nodules all yielded Trichophyton mentagrophytes. The lesions in this dog were similar to granulomatous dermatophytosis, a skin disease that has been reported in Persian cats and one Yorkshire Terrier dog. 相似文献
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Experimental transmission of bovine anaplasmosis (caused by Anaplasma marginale) by means of Dermacentor variabilis and D. andersoni (Ixodidae) collected in western Canada 下载免费PDF全文
Murray W. Lankester W. Brad Scandrett Elizabeth J. Golsteyn-Thomas Neil C. Chilton Alvin A. Gajadhar 《Canadian journal of veterinary research》2007,71(4):271-277
Canadian cattle are free of bovine anaplasmosis, with the exception of 4 isolated incursions since 1968, which were eradicated. It is not known why the disease has not become established in regions of Canada adjacent to the United States where it is endemic. To assess the vector competence of wild-caught ticks in cattle-rearing regions, Dermacentor variabilis and D. andersoni were collected in western Canada and fed on calves experimentally infected with Anaplasma marginale (St. Maries strain). The 2 tick species were equally competent in transmitting A. marginale to splenectomized calves, all 15 tick-exposed calves becoming infected. The prepatent periods in 13 calves ranged from 18 to 26 d and did not vary in relation to the numbers of ticks fed or the duration of transmission feedings. The unusually long prepatent periods in 2 calves (45 and 55 d) were probably due to concomitant Eperythrozoon infection. This study clearly demonstrated that tick species present in western Canada are competent vectors of bovine anaplasmosis. Potential barriers, including climate, must be considered in developing strategies to prevent A. marginale from becoming established in anaplasmosis-free regions. 相似文献
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James E. Childs Laura E. Robinson Ramses Sadek Anthony Madden Mary Elizabeth Miranda Noel L. Miranda 《Preventive veterinary medicine》1998,33(1-4):207-218
We estimated the population density of dogs by distance sampling and assessed the potential utility of two marking methods for capture-mark-recapture applications following a mass canine rabies-vaccination campaign in Sorsogon Province, the Republic of the Philippines. Thirty villages selected to assess vaccine coverage and for dog surveys were visited 1 to 11 days after the vaccinating team. Measurements of the distance of dogs or groups of dogs from transect lines were obtained in 1088 instances (N = 1278 dogs; mean group SIZE = 1.2). Various functions modelling the probability of detection were fitted to a truncated distribution of distances of dogs from transect lines. A hazard rate model provided the best fit and an overall estimate of dog-population density of 468/km2 (95% confidence interval, 359 to 611). At vaccination, most dogs were marked with either a paint stick or a black plastic collar. Overall, 34.8% of 2167 and 28.5% of 2115 dogs could be accurately identified as wearing a collar or showing a paint mark; 49.1% of the dogs had either mark. Increasing time interval between vaccination-team visit and dog survey and increasing distance from transect line were inversely associated with the probability of observing a paint mark. Probability of observing a collar was positively associated with increasing estimated density of the dog population in a given village and with animals not associated with a house. The data indicate that distance sampling is a relatively simple and adaptable method for estimating dog-population density and is not prone to problems associated with meeting some model assumptions inherent to mark-recapture estimators. 相似文献
67.
Larry G. Hansen Elizabeth M. Cozzi Robert L. Metcalf Terry K. Hansen 《Pesticide biochemistry and physiology》1985,24(1):136-148
The oxons of leptophos, its desbromo analog, and its ethoxy analog all inhibit hen brain neurotoxic esterase (NTE) to a similar degree in vitro, but have large differences in minimum effective oral doses for organophosphorus-induced delayed neurotoxicity. The potencies of leptophos and ethoxyleptophos are increased 10-fold when administered to hens intravenously (iv), but the potency of desbromoleptophos is nearly the same whether administered iv or po. Leptophos distributes nearly five times more rapidly from the central compartment than does desbromoleptophos, and its attenuated oral potency may be due to slower net absorption and/or dilution by compartments other than nervous tissue. Intravenously administered phenylphosphonothionates are excreted rapidly into the gastrointestinal tract and a large proportion of the dose is eliminated in the first 48 hr. Indirect evidence indicates that ethoxyleptophos is more rapidly degraded and ethoxyleptophos-inhibited NTE recovers more rapidly than does NTE inhibited by leptophos or desbromomleptophos. It is proposed that differential aging of ethoxyleptophos chiral isomers as well as pharmacokinetic factors may contribute to the apparently anomalous behavior of these three analogs. 相似文献
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Elizabeth Baldwin 《国际木业》2003,(12):47-51
在我刚刚加入Maruhon的时候,公司总裁对我说:“信息是生意的生命之源”,信息流越多,生意做得越旺。在经历了15年的商场生涯后,我发现这是一句至理箴言。你学得越多,知道得越多,分享的越多,你就越能够找到对双方合作的基点。因此,请谨记,交流是促成生意成功的关键。 相似文献