I don't believe in breeds...
Its a backwards way of running cattle.
Didn't some famous orator once say "...a world where all cattle are created equal"
If function, efficiency, durability, disease resistence, milking, calving ease and SIZE were all that people selected for over the past couple hundred years, instead of 'color', 'ear', 'horn' or 'my breeds guidelines', cattle today would be monstrous and productive meat factories- but could also have calves every with no problems.
I doubt old Tom Lasater would have minded his cattle growing as large as elephants- b/c pounds of meat is the business, not head of cattle.