Once the laboratory has grown the bacteria, they can also check if they are resistant or susceptible to a predetermined list of antibiotics (‘susceptibility testing’). While this does not guarantee that an infected cow will be cured by a particular antibiotic, as conditions on a laboratory plate can differ dramatically from conditions in the udder, it is important to be aware of any resistance issues that may be emerging on farm and to choose a treatment that should be effective.
Taking good samples
Good samples yield good results, so hygiene is essential – whichever bacteria you collect in the sample of milk, whether they come from the quarter or from the environment, will be identified by the laboratory. Mixed bacterial infections can occur in mastitis, but when three or more different bacteria are identified in one sample, this is universally recognised as evidence of a contaminated sample.
For step-by-step instructions on taking and handling milk samples in a sterile fashion, see Management Note A in the CellCheck Farm Guidelines for Mastitis Control.
CellCheck Partner Labs
CellCheck continues to work in partnership with the Department of Agriculture, Food and Marine to harmonise methods and standards of commercial services available for mastitic milk samples. The requirements to be recognised as a CellCheck Partner Lab are currently under review, and when agreed will be published on this webpage.