Hopefully you never have to see a calf with frostbitten feet, but if you do, you'll be able to tell what it is.  Not pretty, but undeniable as to the diagnosis.  The calve had been walking so gingerly (from the beginning) on it's hooves before losing them, I was hoping it was a case of arthritis or anything other than frostbite, the way it was slowly, stiffly moving around--not to be.  Unmistakeable when the hoof falls off.

It's not too hard to believe that most folks haven't seen it firsthand though, since as I stated earlier, this is the only 2nd calf in 25 years for us and we have averaged calving from 125 to 200 cows per year during that period.