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W. J. Goodger T. Farver J. Pelletier P. Johnson G. DeSnayer J. Galland 《Preventive veterinary medicine》1993,15(4):235-251
An instrument for assessing milking management practices was used to identify factors associated with udder health. The instrument included 48 individual management variables in 12 categories. Bulk tank somatic cell count (BTSCC) was recorded on 56 randomly selected Dairy Herd Improvement Association (DHIA) dairies, and the dairy's management practices were evaluated on four occasions during November 1988 to July 1989. The log-transformed BTSCC, question score 5 and category scores were subjected to a series of analyses, including principal-component analysis, correlation analysis, multivariate analysis of variance (MANOVA) and stepwise, all-possible-subsets multiple regression. Principal-component analysis was applied to the time-period-specific category scores and major data reduction was not seen for any time period. The correlation analyses between category scores revealed 26 pairs with highly significant correlations. These results indicate that although the categories in the instrument were correlated to the degree that some of the correlations were statistically significant, the strengths of the correlations were not sufficient for the catergories to cluster together in a relatively small number of independent components. The MANOVA results indicated that there was a significant time-period effect. The regression analysis identified sanitation, milking equipment, cow condition, pre-milking procedures and the mastitis control catergories as significantly reducing BTSCC. 相似文献
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Sargeant JM Gillespie JR Oberst RD Phebus RK Hyatt DR Bohra LK Galland JC 《American journal of veterinary research》2000,61(11):1375-1379
OBJECTIVE: To describe the frequency and distribution of Escherichia coli O157:H7 in the feces and environment of cow-calf herds housed on pasture. SAMPLE POPULATION: Fecal and water samples for 10 cow-calf farms in Kansas. PROCEDURE: Fecal and water samples were obtained monthly throughout a 1-year period (3,152 fecal samples from 2,058 cattle; 199 water samples). Escherichia coli O157:H7 in fecal and water samples was determined, using microbial culture. RESULTS: Escherichia coli O157:H7 was detected in 40 of 3,152 (1.3%) fecal samples, and 40 of 2,058 (1.9%) cattle had > or = 1 sample with E coli. Fecal shedding by specific cattle was transient; none of the cattle had E coli in more than 1 sample. Significant differences were not detected in overall prevalence among farms. However, significant differences were detected in prevalence among sample collection dates. Escherichia coli O157:H7 was detected in 3 of 199 (1.5%) water samples. CONCLUSIONS AND CLINICAL RELEVANCE: Implementing control strategies for E coli O157:H7 at all levels of the cattle industry will decrease the risk of this organism entering the human food chain. Devising effective on-farm strategies to control E coli O157:H7 in cow-calf herds will require an understanding of the epidemiologic characteristics of this pathogen. 相似文献
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Galland S Mora N Abert-Vian M Rakotomanomana N Dangles O 《Journal of agricultural and food chemistry》2007,55(18):7573-7579
This work describes the chemical synthesis of O-aryl-beta-D-glucosides and 1-O-beta-D-glucosyl esters of hydroxycinnamic acids. In particular, O-aryl-beta-D-glucosides were efficiently prepared via a simple diastereoselective glycosylation procedure using phase transfer conditions. Despite the lability of its ester linkage, 1-O-beta-D-caffeoylglucose could also be obtained using a Lewis acid catalyzed glycosylation step and a set of protective groups that can be removed under neutral conditions. Hydroxycinnamic acid O-aryl-beta-D-glucosides were then quantitatively investigated for their affinity for the naturally occurring anthocyanin malvin (pigment). Formation of the pi-stacking molecular complexes (copigmentation) was characterized in terms of binding constants and enthalpy and entropy changes. The glucosyl moiety did not significantly alter these thermodynamic parameters, in line with a binding process solely involving the polyphenolic nuclei. 相似文献