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Galactose epimeraseless mutants of Salmonella typhimurium as live vaccines for calves. 总被引:2,自引:1,他引:2 下载免费PDF全文
The purpose of the study was to evaluate the safety and efficacy of a galactose epimeraseless mutant of Salmonella typhimurium administered as an oral vaccine to one week old calves and to investigate properties of galactose epimeraseless mutants which affect their virulence and immunogenicity. The galactose epimeraseless mutant S. typhimurium strain G30D caused diarrhea and fever in three calves to which it was administered orally at a dose of 10(10) organisms; all three calves died following challenge with virulent S. typhimurium ten days postvaccination. Mild illness developed in four calves vaccinated with a dose of 9 X 10(6) organisms and one of these calves survived challenge. Three unvaccinated calves died following challenge. The vaccine organism persisted in tissues and was shed for a prolonged period by calves which received 10(10) organisms. Studies of characteristics of galactose epimeraseless mutants of S. typhimurium showed that, in the presence of galactose, there is selection for secondary mutants which are galactose resistant. The studies indicate that galactose epimeraseless mutants of S. typhimurium are not good candidate live vaccine organisms for use in calves. 相似文献
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American Journal of Potato Research - 相似文献
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Gina M Davis-Wurzler 《Veterinary Clinics of North America: Small Animal Practice》2006,36(3):607-40, vii
Motivation in writing this article stems from many things: a lack of time spent in the veterinary curriculum discussing vaccines, a growing concern(by the general public and the veterinary community) regarding adverse reactions associated with vaccines, and a desire to prevent a recurrence of preventable infectious diseases resulting from a fear-driven cessation of vaccine administration. The objectives of this article are to present a basic review of immunology as related to vaccines, to discuss general guidelines for pediatric vaccines in canine and feline patients,and to offer suggestions as to how we can most positively influence our patients' health from the first visit. 相似文献
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Comparison of the results of abdominal ultrasonography and exploratory laparotomy in the dog and cat
Pastore GE Lamb CR Lipscomb V 《Journal of the American Animal Hospital Association》2007,43(5):264-269
Results of preoperative ultrasonography and exploratory laparotomy were reviewed retrospectively in a series of 100 small animals to assess the agreement between ultrasonographic and surgical findings and to identify abdominal lesions likely to be missed by ultrasonography. Good agreement occurred between ultrasound reports and surgical reports in 64% of the animals, which supported the use of ultrasonography in potential surgical candidates. A major discrepancy was observed between the ultrasound report and surgical findings in 25% of the animals. Of the various types of pathology encountered in the study, gastrointestinal ulceration or perforation was the most likely lesion to be missed by ultrasonography. 相似文献
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Heather E Clarke Helen Kado-Fong David J Maggs 《Journal of veterinary diagnostic investigation》2006,18(4):388-391
The purpose of this study was to report methods currently recommended by commercial laboratories for collecting, shipping, and processing of samples for feline herpesvirus type 1 (FHV-1) testing using polymerase chain reaction (PCR) and to determine the effect of temperature and time on the ability of 1 PCR method to detect FHV-1 DNA in experimental and clinical samples. Eleven laboratories offering FHV-1 PCR were surveyed. There was notable variation in sample types and shipping conditions recommended and PCR protocols used by these laboratories. Subsequently, using a single PCR method, FHV-1 DNA was detected in samples exposed to various temperatures within the laboratory. Finally, FHV-1 PCR was performed on paired clinical samples collected from 25 cats and shipped at ambient temperatures via US Postal Service (USPS) or with an ice pack via a courier. Samples sent by USPS were exposed to significantly longer transit time and arrived at significantly higher temperature than did samples sent by courier. Despite this, all sample pairs yielded concordant results when tested for FHV-1 DNA using this PCR method. Although it may not be necessary for samples collected for detection of FHV-1 DNA using this PCR method to be shipped under the most expedient or temperature-controlled conditions, this should be verified for a variety of PCR assays and sample types. 相似文献
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