Yes and yes.
Per the PMO if Grade A fluid milk leaves a processing facility and shipped in bulk to another milk plant it must be pasteurized before packing.
Bottom of page 32...it is not so direct, but has to be pasteurized if transferred or received into a Grade A milk plant. Also, yes, you will have to pasteurized on Grade A approved equipment, and Grade A facility. This means you will need to apply for milk permit (if you don't have one). You will need an inspector to insect and then approve the facility, and the equipment. Equipment approval requires sanitation review to ensure it meets 3A standard and then testing of equipment (pasteurizer) to meet the requirements. If equipment passes it is sealed and then will require testing every quarter or 6 months (don't recall exactly).
This is all assuming the yogurt you make or will make is Grade A.