The answer to that question is not as simple as you may think. There are many factors that have to be considered. Probably the best way to find out is to talk with the local veterinarian and other goat breeders in your area. Another good source for the answer to that question would be the folks at your local feed store.
Location, climate and environment are all factors that will influence what your goats need to be protected against. For example, some areas are prone to Caseous Lymphadentis (CL) and immunizing against that is a necessity.
We have found that for our herd, and this would also apply to all goats herds, is protection against Enterotoxemia or overeating disease. Our routine is to make sure all of our goats are protected against this disease. We immunize our herd annually in February with Bar-Vac CD/T. This also allows for the protection to be transferred from the doe's milk to newborn kids when they are born in March and April. Each kid is then immunized at three weeks of age with a booster shot given at six weeks of age. From then on, all that is required is the annual booster. We also vaccinate all newly acquired goats just to be sure they are protected. The CD/T vaccine also protects against tetanus.
If you are going to raise goats you should plan on becoming an amatuer veterinarian. That means you will need to keep some basic medicines on hand. Tetanus vaccine, even though the CD/T provides some protection against tetanus, better safe than sorry. Antibiotics like Pro-Pen-G (Penicillin G Procaine) Injectable Suspension is still available without a prescription. We use Excenel RTU EZ, it requires a prescription. Until the FDA does something stupid and makes virtually all antibiotics prescription drugs, many can still be purchased at Feed and Farm Supply Stores.