Charles W. Kaspar

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A 14-month longitudinal study was conducted on four dairy farms (C, H, R, and X) in Wisconsin to ascertain the source(s) and dissemination of Escherichia coli O157:H7. A cohort of 15 heifer calves from each farm were sampled weekly by digital rectal retrieval from birth to a minimum of 7 months of age (range, 7 to 13 months). Over the 14 months of the(More)
Ferroplasma acidarmanus thrives in hot, extremely low pH, metal-rich solutions associated with dissolving metal sulfide ore deposits. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and thin layer chromatography analyses of F. acidarmanus membranes indicate that tetraether lipids predominate, with at least three core lipid(More)
A survey was conducted between March and October of 1994 to determine the prevalence and identify the sources of serotype O157:H7 isolates of Escherichia coli in Wisconsin dairy herds. A stratified sample of 400 farms was identified, and 70 farms with weaned calves less than 4 months old were included in the study. During the prevalence study, 5 of the 70(More)
A total of 765 Escherichia coli isolates from point and nonpoint sources were collected from the Apalachicola National Estuarine Research Reserve, and their multiple-antibiotic-resistance (MAR) profiles were determined with 10 antibiotics. E. coli isolates from point sources showed significantly greater resistance (P < 0.05) to antibiotics and higher MAR(More)
Sterilized seawater was used to assess the effects of temperature and salinity on the survival of Vibrio vulnificus. In the temperature range of 13 to 22 degrees C, numbers of V. vulnificus increased during the 6-day incubation. Temperatures outside this range reduced the time of V. vulnificus survival in sterile 10-ppt seawater. At these restrictive(More)
An Escherichia coli O157:H7 dps::nptI mutant (FRIK 47991) was generated, and its survival was compared to that of the parent in HCl (synthetic gastric fluid, pH 1.8) and hydrogen peroxide (15 mM) challenges. The survival of the mutant in log phase (5-h culture) was significantly impaired (4-log(10)-CFU/ml reduction) compared to that of the parent strain(More)
Forty illness associated phage-type (PT) 4 and PT 8 strains of Salmonella enteritidis were analyzed by the pulsed-field technique of clamped homogeneous electric fields (CHEF) electrophoresis. Using NotI and XbaI, the 40 strains were subdivided by each enzyme into seven restriction endonuclease digestion profiles (REDP). The 35 PT 4 isolates from Austria(More)
A study of Escherichia coli O157:H7 transmission and shedding was conducted with bull calves housed in individual pens within a confined environment. For comparative purposes, the numbers and duration of E. coli O157:H7 shedding in naturally infected calves were monitored after a single purchased calf (calf 156) tested positive prior to inoculation. During(More)
The fate of Escherichia coli O157:H7 was monitored in salami during conditioning of batter, fermentation and drying of sticks, and storage of slices. The raw batter (75% pork: 25% beef, wt/wt, fat content about 20%) was inoculated with a pediococcal starter culture (about 10(8) CFU/g) and a five-strain cocktail of E. coli O157:H7 ( > or = 2 x 10(7) CFU/g)(More)