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Seroagglutination (SAT), enzyme-linked immunosorbent assay (ELISA), and indirect fluorescent antibody staining tests (IFAT) were compared for reliability in the detection of pilus antigens K99, K88, and 987P of Escherichia coli. Test sensitivities were compared using mixtures of piliated bacteria of several strains diluted to a constant optical density with a nonpiliated strain. Relative sensitivities and specificities of the 3 tests were also compared using 55 E. coli strains that had previously been serotyped and characterized for pilus genes by DNA probe. Although specificity was not a serious problem with any of the tests, the SAT was relatively nonsensitive. The IFAT showed the greatest sensitivity of the 3 tests in detecting K88, K99, and 987P E. coli.  相似文献   
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Porcine circovirus type 2 (PCV2) is now recognized as the essential infectious component of porcine postweaning multisystemic wasting syndrome (PMWS). PMWS was first recognized in high-status, specific pathogen-free pigs in Canada in 1991 and is now an economically important disease that affects the swine industry around the world. Recently, reports of genomic studies on PCV2 viruses indicated that 2 distinctive genogroups of PCV2 exist.4,10 This report involves the results of a study on the distribution of predominant PCV2 genogroups recovered from samples taken from PMWS-affected and PMWS-nonaffected farms on the island of Ireland over a 9-year period and the results of a study on PCV2 genogroup recovery from fecal samples taken from a farm in Northern Ireland from 2003 to 2005 that was first diagnosed as PMWS positive in August 2005. The results indicate that, although at least 2 distinct genogroups of PCV2 have been circulating on pig farms on the island of Ireland, there does not appear to be a direct relationship between infection with these different genogroups of PCV2 and the development of PMWS.  相似文献   
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Amoxycillin, a new broad spectrum semi-synthetic penicillin was subjected to preliminary clinical testing in 351 cases in dogs and 264 in cats in veterinary practices. Two formulations were used: capsules by mouth and an aqueous suspension by injection. Those taking part were asked to use amoxycillin in the treatment of all conditions that they considered required an antibiotic and to report their results in terms of success or failure according to criteria laid down. Samples were taken whenever practicable for bacteriology. Dose ranges were 4 to 11 mg per kg for the oral capsules twice daily in dogs and most cats and 11 mg per kg once daily in some cat cases over five days and 2 to 7 mg per kg for the injectable suspension once daily in both species for three to five days. Results for the full range of conditions are given in tabulated form. Overall percentage of success according to the criteria laid down was 80.1%.  相似文献   
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