Just adopted our 3rd shelter pup. She is apprx 4 months old and is solid white with pink skin. Our vet gave her a clean bill of health. Gave her a bath using Mane n Tail shampoo. Since then she has been scratching and biting herself. Here skin looks healthy with no flaking or breaks in the skin. I am looking for recommendations for a shampoo or perhaps a supplement that will help her itchy condition. Thanks!