Cracking paw advice

hi everyone i am just wondering if anyone has any ideas how to prevent cracking and bleeding paws.
My bull mastiff is 8.5 stone in weight and got big paws, unfortunately whenever he goes for a walk his paws split and bleed, this isn't down to distance as happens whether he goes on short or long walks.
Doesn't seem to bother him but i'm worried about infection any advice would be greatly received

What does the vet say?

the vet just says that he is heavy on his feet

wondered if anyone has tried mushers wax, or boots and if anyone could recommend anything similar to mushers wax or recommend footwear, must be good enough to deal with 8.5 stone of bull mastiff