کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2440686 1108124 2007 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Relationship Between Antimicrobial Drug Usage and Antimicrobial Susceptibility of Gram-Positive Mastitis Pathogens
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Relationship Between Antimicrobial Drug Usage and Antimicrobial Susceptibility of Gram-Positive Mastitis Pathogens
چکیده انگلیسی
The objective of this study was to analyze relationships between usage of antimicrobial drugs on dairy farms and results of antimicrobial susceptibility testing of mastitis pathogens. Exposure to selected antimicrobial drugs (n = 10) was standardized by calculation of the number of defined daily doses used per cow. Farms (n = 40) were categorized based on amount of antimicrobial exposure: organic (no usage); conventional-low usage (conventional farms not using or using less than or equal to the first quartile of use of each compound); and conventional-high usage (conventional farms using more than the first quartile of a particular compound). The minimum inhibitory concentration (MIC) of selected antimicrobial drugs was determined using a commercial microbroth dilution system for isolates of Staphylococcus aureus (n = 137), coagulase-negative staphylococci (CNS, n = 294), and Streptococcus spp. (n = 95) obtained from subclinical mastitis infections. Most isolates were inhibited at the lowest dilution tested of most antimicrobial drugs. Survival curves for Staph. aureus and CNS demonstrated heterogeneity in MIC based on the amount of exposure to penicillin and pirlimycin. For CNS, farm type was associated with the MIC of ampicillin and tetracycline. For Streptococcus spp., farm type was associated with MIC of pirlimycin and tetracycline. For all mastitis pathogens studied, the MIC of pirlimycin increased with increasing exposure to defined daily doses of pirlimycin. The level of exposure to most other antimicrobial drugs was not associated with MIC of mastitis pathogens. A dose-response effect between antimicrobial exposure and susceptibility was observed for some pathogen-antimicrobial combinations, but exposure to other antimicrobial drugs commonly used for prevention and treatment of mastitis was not associated with resistance.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Dairy Science - Volume 90, Issue 1, January 2007, Pages 262-273
نویسندگان
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