My Ebt had very thick skin on her pads and was once sedated and it was cut off, i was told to keep her off concrete as much as poss and regulary rub lanolin into them but it made no difference. They called it digital keritosis, apparently cows get it on their noses! Sometimes she used to chew her paws til they bled and got infected but i was told this was not related and was caused by an allergy, the only way to keep this under control was a steriod called medrone which she was on from the age of 2 til her death this summer age nearly 15 with no side effects and a much happier life.