The long-term absence of vitamins and mineral substances in dogs' diet foods could cause skin disease. The absence of vitamin A, copper and zinc could cause skin disease and hair loss. Indefinite hair loss usually is directly related to the nutrients, so changing dog's diets into vegetarian diet foods could improve these problems.
 
Kidney disease and kidney stone in dogs must be strictly controlled assimilation of protein, phosphorus and sodium in their diet foods to maintain stability of dogs' health, besides the treatment. In order to avoid excess assimilation of animal protein, the best way is to let dogs to eat vegetarian diet goods to maintain their health.