I thought Lottie had been excessively moulting, but realized the last couple of days she seems to be pulling her fur out in clumps. I've just found a bare patch on her which doesn't look red or inflamed. She's nearly 17 years old, has a fantastic silky & shiny coat (always has done), eating well, still loving and very alert. She was diagnosed with hyperthyroidism a few months ago which we got under control and she's started putting weight back on. Anyone have any ideas what's causing this?