Why do dogs get dermatitis and eczema?

The root cause of skin disease in dogs is still due to a decrease in skin resistance and microbial invasion. Contact with allergic substances, cleaning seclusion excessive licking hair, bite, scratch, mosquitoes and ectoparasite bites and some drug stimulation. Environmental causes: unclean skin, dirt irritation, dampness in the living place, lack of certain nutrients in the body and other factors may cause eczema. Life causes: Daily bathing without thorough blow-drying, drinking water sources not closed, rainy days when the dog is out without drying the hair may also cause eczema.