Hey everyone
My boy is a white stafford, he has a wheat and gluten allergy which is kept well under control with monitored food and ingredients etc.
But he is getting really bad for biting his nails, sometimes to the point of ripped nails and sore pads

He is exercised twice every day, fed wellbeloveds and butchers and has a happy attitude and good outlets for boredom. (springpole etc)
What do you think could be causing this?
Any help appreciated as I dont like have to keep telling him no for doing it (which can be ten times a day), Id rather find the cause and stop it alltogether!
We have used bitter apple spray and it doesnt work he just nibbles through it, he has sensitive skin shampoo as we thought this might help too but no.
Please help!!