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Objective: To determine the prevalence of selected virulence genes and the antimicrobial susceptibility of multidrug-resistant (MDR) Escherichia coli isolated from diarrheic neonatal calves., Sample: 97 E coli isolates from diarrheic neonatal calves., Procedures: E coli isolates were tested via PCR assay for 6 virulence genes and susceptibility to 17 drugs belonging to 9 classes. A 2-sample test of proportions was used to make comparisons between proportions of virulent and avirulent MDR isolates., Results: 23 of 97 (23.7%) isolates were virulent, and 74 (76.3%) were avirulent. Of the 23 virulent isolates, 15 (65.2%) were positive for K99, 14 (60.9%) for F41, 12 (52.2%) for STa, 9 (39.1%) for Stx1, 6 (26.1%) for intimin, and 0 (0%) for Stx2. Twenty of 23 (87.0%) virulent isolates expressed ≥ 2 virulence genes, and 3 of 23 (13.0%) were positive for 1 virulence factor. Eight of 23 (34.8%) virulent isolates expressed STa, K99, and F41, whereas 1 of 23 (4.4%) was positive for STa, F41, intimin, and Stx1. The second most frequent gene pattern was Stx1 and intimin. Twenty of 23 (87.0%) virulent isolates were MDR; the highest prevalence of resistance was recorded for the macrolide-lincosides, followed by the tetracyclines and penicillins. Also, 17 of 23 (74.0%) virulent isolates were resistant to sulfadimethoxine, and 10 of 23 (43.5%) were resistant to trimethoprim-sulfamethoxazole. Additionally, 60 of 74 (81.0%) avirulent isolates were MDR., Conclusions and Clinical Relevance: The prevalence of multidrug resistance was comparable for virulent and avirulent E coli isolated from diarrheic neonatal calves. Cephalosporins and aminoglycosides had reasonable susceptibility.

An outbreak of respiratory disease at a farmed cervid facility resulted in isolation and identification of Mycoplasma boris in four affected white-tailed deer (Odocoileus virginianus) fawns. Microscopically, pulmonary lesions similar to those associated with M. bovis infections in calves, inclulding lymphoplasmacytic peribronchiolar cuffing and caseonecrotic bronchiectasis, were present. Arcanobacterium pyogenes was recovered from lung tissue as well. This report indicates that M. bovis can be associated with respiratory disease in white-tailed deer.

An adult Chinese red panda (Ailurus fulgens styani) transported by airplane from Florida to a North Dakota zoo died 1 week after arrival. Grossly, an interscapular abscess, subcutaneous inflammation, lymphadenitis, and pulmonary abscesses were observed. Microscopic findings included necrotizing inflammation in liver, lung, lymph node, and spleen. Chromobacterium violaceum was cultured from the interscapular abscess, liver, lung, and spleen and was injected into Swiss Webster mice. These mice died 18 hours postinoculation, and C. violaceum was cultured from liver, lung, and spleen. Chromobacterium violaceum is a sporadically reported but highly virulent pathogenic bacterium of both animals and humans typically found as a soil and water inhabitant of tropical and subtropical regions.