Determination of causative agents of mastitis and their sensitivity to antibiotics

The milk sample for determination of causative agents of mastitis can be taken by the owner of the cow or the veterinary doctor according the owner’s request. We recommend to use the containers prepared by UAB Pieno tyrimai with a preservative (blue coloured) that can be ordered in advance. The samples of milk may be delivered straight to the laboratory of UAB Pieno tyrimai or handed over to the driver of the laboratory. For any additional information, please contact the information manager (ph.: 8 37 363653, mob. ph. 8 687 15553). Samples have to be taken as described and the cover letter for the determination of causative agents of mastitis shall be filled.

Sampling for determination of causative agents of mastitis and their sensitivity to antibiotics

1. The sample of milk is taken from each quarter of udder into a sterile container or containers with a preservative (blue coloured) prepared by the laboratory for the determination of presence of causative agent of mastitis. The sample should be taken at the start of milking. The 40 ml sample shall be labelled according to the procedure:
2. The udder shall be dry and clean. Please wash and disinfect your hands before taking the sample.
3. Clean the tips of teats. Clean the tip of each teat with a cotton or a gauze soaked in 70% alcohol solution or any other disinfectant.
4. Start the sampling from the closest teat by milking 4-5 streams of milk from each teat. This allows to avoid bacteria from inter-channel, as the sample from the milk gland is necessary.
5. By holding the test-tube in a hand, remove the cover without contaminating it. Do not place the cover on the floor or any other surface to avoid contamination.
6. Keep the test-tube angled to prevent the contact with the tip of the teat. After taking the sample, close the container quickly and tumble several times.
7. Cold-kept samples shall be delivered to the laboratory within 12 hours from sampling. The samples of milk may be delivered to the laboratory by a customer himself or handed over to the driver of UAB Pieno tyrimai.

• The causative agents of mastitis identified in the laboratory include Staphylococcus aureus, coagulase-negative staphylococci (CNS), Streptococcus agalactiae, groups set for other streptococci according to Lancefield classification (A, B, C, D, F, G), Escherichia coli, etc.
• The sensitivity of causative agents of mastitis to amoxicicline, amoxicicline with clavulanic acid, cephalexin, enrofloxacin, gentamicin, neomycin, cloxacilllin, kanamycin, penicillin, ampicillin, streptomycin, bacitracin, lincomycin, tetracycline is evaluated. The list of indicated antibiotics is subject to change.

The test for causative agents of mastitis is carried out and their sensitivity to antibiotics is determined by using a method based on the ability of causative agents of mastitis to form the characteristic colonies on a solid agarised nutrition medium which are then tested by identifying the type of the causative agent and their sensitivity to individual antibiotics through a disk diffusion method.

The results of the tests performed are presented to the customer by issuing a document of a specified form – test protocol in a way coordinated with the customer (sent by e-mail, regular mail, handed over when taking other milk samples from the customer). In case of need to receive test results by regular mail, the customer must cover the postal costs.