16S of  bovine teat apex samples
Teat apex, milk, and environmental samples were collected from ten primiparous cows at 7 days in milk (DIM). Following fat removal, DNA was extracted from milk samples and control samples using the PowerSoil DNA Isolation Kit (cat. no. 12888-100, Qiagen, USA). DNA from teat apex swab samples was extracted using the DNeasy Blood and Tissue Kit (cat. no. 69504-50, Qiagen, USA). All extractions were performed according to the respective manufacturers protocols.