FIG. 2.

Challenge virus detection by RT-PCR on RNA extracted from cells in mammary secretions. Amplification was performed with the VIF5/ENV1 primer pair, and a Southern blot of the amplified products was hybridized with the ³²P-labeled TATH oligonucleotide probe. The CGAP1/CGAP2 primer pair was used to amplify the caprine housekeeping gene GAPDH as an internal control. Molecular size markers are indicated at the left.