Analyses of mastitis pathogens in milk samples from Holstein dairy cattle Milk samples should be analysed by PCR, bacterial culture and MALDI-ToF to screen for intra-mammary infections. In January 2016 the field trial and collection of milk samples will start where samples will be collected every Monday the first two weeks of every month in a period of twelve months. Two farms are partici-pating in the project and will be visited once a month. All milking cows in the participating farms will be sampled for one composite milk sample and one sterile quarter milk sample per quarter resulting in 5 samples per cow to be analysed. Composite samples should be analysed by PCR and quarter samples with bacterial culture and MALDI-ToF in some cases. Approximately 25 000 sterile milk samples and 6 000 composite milk samples will be sampled and analysed during the 12 months.