Economic assessments from experimental research trials of feedlot cattle health and performance: a scoping review.

Animal husbandry decisions for feedlot cattle may be based on economic or financial impacts reported from livestock research trials comparing interventions such as health practices or performance technologies. Despite the importance of economic assessments to production management decisions, there are no consensus guidelines for their methods or reporting. Thus, we hypothesized that methods and reporting of economic assessments in the scientific literature are inconsistent. This scoping review describes the types of economic assessments used to evaluate the costs and benefits of interventions in feedlot trials, how measured health and performance outcomes are utilized in economic evaluations, and the completeness of reporting. A structured search was used to retrieve peer-reviewed articles (published in English) on experimental trials performed in Australia, North America, or South Africa, which reported feedlot cattle health, performance, or carcass characteristics and included an economic outcome. A total of 7,086 articles were screened for eligibility; 91 articles (comprising 113 trials) met the inclusion criteria. Trial characteristics, methods, and reporting data were extracted. A primary outcome was stated in only 36% (41/113) of the trials. Of these 41 trials, an economic outcome was reported as a primary outcome in 18 (44%). Methodology for the economic assessment was reported for 54 trials (48%), the type of economic assessment was explicitly stated for 21 trials (19%), and both the type of economic assessment and methodology used were reported for 29 trials (26%); neither were reported for nine trials (8%). Eight types of economic assessments were explicitly reported: cost-effectiveness, cost-benefit analysis, enterprise analysis, partial budget, break-even analysis, profitability, decision analysis, and economic advantage. From the trials that did not report an assessment type, three were identified: partial budget, enterprise analysis, and gross margin analysis. Overall, only 32 trials (28%) reported economics as an outcome of interest, the methodology used or the type of assessment, and values, sources, and dates for at least some of the price data used in the analysis. Given the variability in methods and inconsistent reporting for feedlot trials identified by this scoping review, a guideline to facilitate consistency on appropriate methods and reporting is warranted.

A systematic review and meta-analysis of published literature on prevalence of non-O157 Shiga toxin-producing Escherichia coli serogroups (O26, O45, O103, O111, O121, and O145) and virulence genes in feces, hides, and carcasses of pre- and peri-harvest cattle worldwide.

OBJECTIVE: The objective of this study was to summarize peer-reviewed literature on the prevalence and concentration of non-O157 STEC (O26, O45, O103, O111, O121, and O145) serogroups and virulence genes (stx and eae) in fecal, hide, and carcass samples in pre- and peri-harvest cattle worldwide, using a systematic review of the literature and meta-analyses. DATA SYNTHESIS: Seventy articles were eligible for meta-analysis inclusion; data from 65 articles were subjected to random-effects meta-analysis models to yield fecal prevalence estimates. Meta-regression models were built to explore variables contributing to the between-study heterogeneity. RESULTS: Worldwide pooled non-O157 serogroup, STEC, and EHEC fecal prevalence estimates (95% confidence interval) were 4.7% (3.4-6.3%), 0.7% (0.5-0.8%), and 1.0% (0.8-1.1%), respectively. Fecal prevalence estimates significantly differed by geographic region (P < 0.01) for each outcome classification. Meta-regression analyses identified region, cattle type, and specimen type as factors that contribute to heterogeneity for worldwide fecal prevalence estimates. CONCLUSIONS: The prevalence of these global foodborne pathogens in the cattle reservoir is widespread and highly variable by region. The scarcity of prevalence and concentration data for hide and carcass matrices identifies a large data gap in the literature as these are the closest proxies for potential beef contamination at harvest.

Association between Tulathromycin Treatment for Bovine Respiratory Disease and Antimicrobial Resistance Profiles among Gut Commensals and Foodborne Bacterial Pathogens Isolated from Feces of Beef Steers.

ABSTRACT: This study was conducted to evaluate the association between a therapeutic dose of tulathromycin for bovine respiratory disease in beef steers and the antimicrobial and multidrug resistance profiles of the gastrointestinal tract commensals Escherichia coli and Enterococcus spp. and the foodborne pathogens Salmonella enterica and Campylobacter spp. isolated from fecal samples. Individual fecal samples were collected on days 0, 14, and 28 from 70 beef steers that were housed in a single pen and had been treated or not treated with tulathromycin. Samples were cultured for bacterial isolation, and isolates were tested for antimicrobial susceptibility with the broth microdilution method to determine the MICs of clinically relevant antimicrobials used in both human and veterinary medicine. Generalized linear mixed effects models were fitted to estimate the prevalence of the bacterial species and the prevalence of resistant isolates over time and between treated and nontreated cattle and of multidrug-resistant isolates. Model-adjusted mean prevalences of E. coli, Enterococcus spp., S. enterica, and Campylobacter spp. were 99.5, 85.9, 1.5, and 17.7%, respectively. The prevalence of erythromycin-resistant Enterococcus spp. was significantly higher on day 14 (59.7%) than on day 28 (22.2%). A higher prevalence of erythromycin-resistant Enterococcus spp. was found in samples from treated (59.3%) than in samples from nontreated (27.6%) animals. Multidrug resistance (three or more antimicrobial classes) was observed in 8.4% of E. coli isolates and 62.7% of Enterococcus isolates. The administration of tulathromycin was significantly associated with an increased prevalence of erythromycin-resistant Enterococcus spp. isolates.

Survey of emergency response plans for managing the movement of cattle during a foot-and-mouth disease outbreak in North America.

OBJECTIVE: To collect information from US state animal health officials (SAHOs) and beef feedlot managers and veterinarians regarding emergency response plans for movement of cattle in the event of a foot-and-mouth disease (FMD) outbreak in North America. SAMPLE: 36 SAHOs, 26 feedlot veterinarians, and 7 feedlot managers. PROCEDURES: 3 versions of an electronic questionnaire were created and distributed to SAHOs and US feedlot veterinarians and managers to gather information about planned or expected responses to an FMD outbreak that originated at 1 of 3 geographic locations (Mexico or Canada, a bordering state, or a nonbordering state). Descriptive data were reported. RESULTS: All respondents recognized that the risk of FMD transmission to livestock in their area or care increased as the outbreak got closer in proximity to their location. Most SAHOs indicated that they would immediately close their state's borders to livestock movement at the beginning of an FMD outbreak, particularly if the disease was identified in a bordering state. During an extended FMD outbreak, 29 of 36 (80.6%) SAHOs reported they would resume interstate movement of cattle under some conditions, including enhanced permitting, whereas feedlot veterinarians and managers commonly reported they would be willing to receive cattle from states where no FMD-infected animals were identified, regardless of permit requirements. CONCLUSIONS AND CLINICAL RELEVANCE: Information gained from this survey can be used to inform disease modeling and preparedness efforts to facilitate business continuity of US beef feedlots in the event of an FMD outbreak in North America.

Genomic-based epidemiology reveals independent origins and gene flow of glyphosate resistance in Bassia scoparia populations across North America.

Genomic-based epidemiology can provide insight into the origins and spread of herbicide resistance mechanisms in weeds. We used kochia (Bassia scoparia) populations resistant to the herbicide glyphosate from across western North America to test the alternative hypotheses that (i) a single EPSPS gene duplication event occurred initially in the Central Great Plains and then subsequently spread to all other geographical areas now exhibiting glyphosate-resistant kochia populations or that (ii) gene duplication occurred multiple times in independent events in a case of parallel evolution. We used qPCR markers previously developed for measuring the structure of the EPSPS tandem duplication to investigate whether all glyphosate-resistant individuals had the same EPSPS repeat structure. We also investigated population structure using simple sequence repeat markers to determine the relatedness of kochia populations from across the Central Great Plains, Northern Plains and the Pacific Northwest. We found that the original EPSPS duplication genotype was predominant in the Central Great Plains where glyphosate resistance was first reported. We identified two additional EPSPS duplication genotypes, one having geographical associations with the Northern Plains and the other with the Pacific Northwest. The EPSPS duplication genotype from the Pacific Northwest seems likely to represent a second, independent evolutionary origin of a resistance allele. We found evidence of gene flow across populations and a general lack of population structure. The results support at least two independent evolutionary origins of glyphosate resistance in kochia, followed by substantial and mostly geographically localized gene flow to spread the resistance alleles into diverse genetic backgrounds.

Common garden test of range limits as predicted by a species distribution model in the annual plant Mimulus bicolor.

PREMISE OF THE STUDY: Direct tests of a species distribution model (SDM) were used to evaluate the hypothesis that the northern and southern edges of Mimulus bicolor's geographical range are limited by temperature and precipitation. METHODS: Climatic suitability was predicted using an SDM informed only by temperature and precipitation variables. These predictions were tested by growing plants in growth chambers with temperature and watering treatments informed by weather stations characteristic of environments at the geographic center, edges, and outside the range. An Aster analysis was used to assess whether treatments significantly affected lifetime flower production and to test for local adaptation. The relationship between climatic suitability and lifetime flower number in the growth chambers was also evaluated. KEY RESULTS: The temperature and watering treatments significantly affected lifetime flower number, although local adaptation was not detected. Flower production was significantly lower under the two edge treatments compared to the central treatment. While no flowers were produced under the beyond-south treatments, flower production was greatest under the beyond-north treatment. These results suggest a hard abiotic limit at the southern edge, and suitable temperature and precipitation conditions beyond the northern edge. While predicted climatic suitability was significantly lower at the range edges, there was no correlation between the climatic suitability of the weather stations' locations and flower production. CONCLUSIONS: These results suggest that temperature and precipitation play a significant role in defining the distribution of M. bicolor, but also indicate that dispersal limitation or metapopulation dynamics are likely important factors restricting access to habitable sites beyond the northern range limit.

Demographic and population-genetic tests provide mixed support for the abundant centre hypothesis in the endemic plant Leavenworthia stylosa.

The abundant centre hypothesis (ACH) assumes that population abundance, population size, density and per-capita reproductive output should peak at the centre of a species' geographic range and decline towards the periphery. Increased isolation among and decreased reproductive output within edge populations should reduce within-population genetic diversity and increase genetic differentiation among edge relative to central populations. The ACH also predicts asymmetrical gene flow, with net movement of migrants from the centre to edges. We evaluated these ecological assumptions and population-genetic predictions in the endemic flowering plant Leavenworthia stylosa. Although populations were more spatially isolated near range edges, the geographic centre was surrounded by and not coincident with areas of peak population abundance, and plant density increased towards range edges. Per-capita seed number was not associated with distance to the range centre, but seed number/m(2) increased near range edges. In support of ACH predictions, allelic diversity at 12 microsatellite loci declined with distance from the range centre, and pairwise FST values were higher between edge populations than between central populations. Coalescent analyses confirmed that gene flow was most infrequent between edge populations, but there was not an asymmetric pattern of gene flow predicted by the ACH. This study shows that among-population demographic variability largely did not support the ACH, while patterns of genetic diversity, differentiation and gene flow were generally consistent with its predictions. Such mixed support has frequently been observed in tests of the ACH and raises concerns regarding the generality of this hypothesis for species range limits.

The efficacy of a multicultural prevention intervention among urban American Indian youth in the southwest U.S.

This study explored how a non-targeted group of ethnic minority youth might or might not benefit from a prevention intervention focused on other cultural groups. The study specifically evaluated the effects of an evidence-based drug prevention curriculum with a sample of urban American Indian youth in the southwest U.S., most of whom self-reported multi-ethnic heritages. Using growth curve modeling, this research examined the developmental trajectory of drug use for these youth, and compared it with the trajectory of youth from other racial/ethnic groups at pre-intervention, post-intervention, and two follow up time periods. Results indicate that alcohol and marijuana use increased from pre-intervention across subsequent time periods for all youth. The drug use of the American Indian youth in the treatment group increased on some measures. Specifically, they reported a steeper trajectory in the amount and frequency of alcohol and marijuana use compared to the youths in the treatment groups with other racial/ethnic identifications. The implications of these findings for the development of culturally grounded prevention programs for multi-ethnic, urban American Indian youth are discussed. EDITORS' STRATEGIC IMPLICATIONS: This research provides a specific example, but also makes a strong global argument, for the need to develop and evaluate prevention programs that are culturally grounded in the worldview of the target group.

Listening begins at home.

Procter & Gamble has long been regarded as a major power of the marketing world and a prime training ground for marketers. But in the summer of 2000, with half of P&G's top 15 brands losing market share and employee morale in ruins, company executives realized that the marketing organization was in trouble. Training programs had been dramatically downsized and in some cases eliminated, employees were being fast-tracked up the career ladder without sufficient time to develop and hone their skills, mentoring had all but disappeared, and the marketing career path had lost its prestige. In an attempt to rebuild P&G's marketing strength, James Stengel, the heir apparent to the chief marketing officer position, began working with University of Cincinnati professors Chris Allen and Andrea Dixon on a new training program to fix the weaknesses in the marketing organization. But when the two professors began interviewing P&G senior executives, they discovered that the plans in motion for mapping out the marketing group's recovery were based not on data but on the intuition of a few individuals at corporate headquarters. So began the most comprehensive internal research endeavor in P&G marketing's history. Using the company's existing process for consumer research, Allen and Dixon shadowed employees, conducted one-on-one interviews, held focus-group sessions, and surveyed 3,500 members of the marketing staff to learn what the company was doing right--and wrong--and what mattered most to its people. The results led to the most sweeping redesign of P&G's marketing organization in 60 years. In this article, the authors explore the value of listening to employees--and truly hearing them. One of their conclusions: A structured research process can show you what's really on employees' minds.