When I had cattle, I used it mixed with salt,to be eaten in small amounts or licked by the cattle.Never heard of use on dogs,but you never get too old to learn something new every day.Good luck and good hunting.
J, I know that there are much better sources of protein than cottonseed meal or cake. Meat scraps would do you much better if you wished to add protein to your hound's daily diet. Try to find some 'cracklings' as the local slaughter house as this would add both fat and protein. Dogs would probably find the taste of the cottonseed to be unpleasant unless you masked it somehow. Just an old man's opinion here.