Not necessarily, you can buy one, just make sure shes a good age, in good health, healthy and clean udders and shes not a stripper -- they'll be no good to you but a lot of farmers will still try to get rid of them.

Oh, watch out for mastitis as well, you'll get that on cattle that have been poorly taken care of. Redwater can be a slight possibility as well if she's an open grazer in wet fields with too long of grass.

Only if you want her to continue to produce milk. They continue for about 9-10 months after the birth of the calf.

If you are trying for max possible milk production, some one did some breeding among her ancestors.

If you want to get milk, you do.