LUH Antibiotic Susceptibility Testing
As of September, 2018 the Lab for Udder Health will no longer offer Antibiotic Susceptibility testing for mastitis isolates. The disk diffusion test is a very simplified system that lacks many of the factors that contribute to disease outcomes in a living animal. Several studies have found poor or no correlation between pathogen sensitivity and resistance in laboratory settings and clinical cure rates. With the limited translation from lab results to field results there is currently no significant benefit from utilizing sensitivity and resistance testing for mastitis pathogens. Instead, treatment decisions should be based on established farm protocols that factor in individual cow eligibility criteria for treatment, such as udder health history, age and concurrent disease, in combination with the general susceptibility profile of the suspected or confirmed pathogen at hand.
If you have a particular isolate of interest, MIC testing is available through our Bacteriology lab.