Warming up a calf is definitely not an appropriate or timely response for a calf not breathing. Calf not breathing after birth - stick or straw in the nose to stimulate the calf, hand in mouth to clear mucus, compressions on the side of the calf to stimulate it and give some movement to the lungs, mouth to nose breaths if so inclined. My point is that warming a chilled distressed breathing calf is a real need sometimes, but I was never inclined to throw a bucket of cold water on a distressed newborn. I suspect that distressed calves that were warmed after birth are more likely to be alive a week later than distressed calves that have a bucket of cold water dumped on them.