D G Renter

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..However, focusing on O157:H7 in food safety and surveillance programs may allow other Stx-producing bacteria, which appear to be widespread in cattle, to go undetected...

..Although the prevalence of Salmonella in free-ranging deer appears to be low, the serovars recovered are known to be pathogenic to humans and animals...

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..001). Our results indicate that E. coli O157 gut persistence and faecal prevalence increased in calves fed DDG, which potentially have important implications for food safety...

..The prevalences of E. coli O157:H7 were 14.8 and 14.2% for organically and naturally raised cattle, respectively. No major difference in antibiotic susceptibility patterns among the isolates was observed...

..2; 95% confidence interval, 6.3-43.6). Our results suggest that high shedders within a truckload at slaughter could be a target for mitigation strategies to reduce the probability of preevisceration carcass contamination...

..coli O157 and the concentration of selected antimicrobial resistance genes, but does not appear to affect antimicrobial susceptibility patterns in Enterococcus and generic E. coli isolates...

..6; CI, 1.0 to 2.6). Our results suggest that preharvest interventions for reducing E. coli O157:H7 contamination of carcasses should focus on truckload (cohort)-level and hide mitigation strategies...

..The form of DG had no impact on E. coli O157:H7; however, fecal shedding was associated with the DG inclusion level...

..05) modified by gender, season and mean arrival BW of the cohort. Combining data on BW loss during transport with cohort demographics could allow a more precise prediction of health and performance of feedlot cattle...

..05) with low Stx2 production in human isolates. Therefore, Q933 was a better indicator of high Stx2 production by human and bovine isolates and may be a useful screening method to assess their potential to cause human disease...

..e., cohort region of origin, mean arrival BW, gender, and the season of the year) of the cohort. Knowledge of the distance traveled during transportation could allow a more precise prediction of cattle feedlot health and performance...

..Although associations with health outcomes were not identified, seroconversion to M. bovis was associated with a decreased rate of weight gain during the study period...

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..The results support a complex ecology for E. coli O157 in feedlot operations, with factors associated with exposure and transmission likely acting at a common level for multiple feedlots, within feedlots, and within pens of cattle...

..coli O157 in cattle feces or water. Management risk factors must be interpreted with caution but the results reported here do not support the use of coliform counts as a marker for E. coli O157 contamination of feed or water...

..Estimated effects from our model could be useful for managing financial risks associated with adverse health events based on data that are routinely available...

..Our results are the first to demonstrate that there are several temporal patterns of BRDC repeatedly observed among cohorts of feedlot cattle, and that these BRDC patterns may differentially affect cattle health and performance...

..05) at 24 h than 0, 0.5, or 1 g DDG. The results indicate that there is a positive association between DDG and E. coli O157 in cattle, and the findings should have important ramifications for food safety...

..coli O157...

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..Our data indicate that multiple non-O157 STEC serotypes may be present in cattle feces, yet are unlikely to be recovered from the corresponding beef carcasses when 20 colonies per sample from PCR-positive broth cultures are analyzed...

..This research indicates that timing of initial BRD treatment is associated with performance and health outcomes...

..coli O157 previously described for confined cattle operations is also evident in extensively managed range cattle environments...

..Further research is needed to understand inconsistencies between studies of E. coli O157:H7 prevalence and potential associations with DG and grain-processing methods...

..Truckload may be an important factor in the potential transmission of E. coli O157, but isolates from carcasses also may be similar to those from feces of cattle on different truckloads and harvest days...

..These data illustrate the importance of capturing premiums when operating natural and organic production systems to maintain economic viability...

..Results from the present study should be considered when these diagnostic methods are used to evaluate BRD outcomes in clinical and research settings...

..Results indicate a high prevalence of Salmonella in this population of cattle treated for apparent respiratory disease, but that effects associated with clinical outcomes may depend on the Salmonella strain...

..The study confirms our previous finding of the positive association between feeding DG and fecal shedding of E. coli O157:H7...

..This health difference likely accounted for the differences in feed performance between the treatment groups...

..coli O157. Estimates of sensitivity and specificity enable appropriate application of methods and interpretation of results and may enhance applied research, surveillance, and risk assessments...

..8%). In this study, calves administered a program with fewer injections indicated less aversion to program administration than those administered more injections, but experienced greater morbidity and poorer performance...

..To determine the usefulness of physiologic, behavioral, and pathological changes as objective indicators of early respiratory disease in calves with Mannheimia haemolytica pneumonia...

..To determine the accuracy of accelerometers for measuring behavior changes in calves and to determine differences in beef calf behavior from before to after castration...

..The model presented is valuable in assessing the effect of control strategies and the effects of disease parameters on BVDV spread in beef herds...

..This model predicts the risk of BVDV introduction for individual herds based on management decisions, and should prove to be a useful tool to help cow-calf producers in controlling the risk of importing BVDV to a naïve herd...

..Although pen-level prevalence estimates for Shiga toxins and non-O157 serotypes seem high relative to O157:H7, further effort is required to determine the human health significance of non-O157 serotypes of STEC in feedlot cattle...