Scheme 1. MALDI-MS bacterial identification in bovine semen general workflow. After thawing the semen straws, 50 mL are collected and refrigerated. Semen
samples are seeded in BHI and cultured for 24 hours. If BHI turbidity is observed, samples can be directly spotted in the MALDI target plate after centrifugation
(ICM strategy) or can be submitted to protein extraction before being spotted in the MALDI target plate (PEM strategy). All samples are covered with the organic
matrix CHCA. MALDI-MS sample acquisition and database search are performed automatically. All the procedure takes 15 to 20 min/sample, so that the overall
process of bacterial identification in semen samples can be performed in 1 day.