My 3 yr old female started shedding after suddenly developing a thicker white undercoat. We live in Maine and have had her for 2 years but she didn't shed the first year. Should I be concerned? Or just get a good brush? Zoom Groom is OK but not great. Also any thoughts on raw/ freeze dried food diet? She has been on it and digestion & appetite is way better, but heard it may affect her coat...