Do your unspayed females only grow coat at certain times? As in, if the vet clips a patch when the girl has just grown in a new coat, would you expect that patch to stay short until the girl sheds out and grows a whole new coat?
They don't continuously grow coat right? Although I notice once spayed they shed and grow new almost constantly.
We have a girl that had a non-cancerous tumor in the middle of her chest. The Vet cut it out and her whole chest was shaved. It took about two and a half months for the hair to grow back to the length of the rest of her coat so we could show her.
That's because spaying affects hormones. To get coat to grow in fast give 2 fish oil and 1 vitamin E human grade capsules in the food. We had some areas of no hair due to a false pregnancy in July of 2014. My daughter had a 4-h show with that dog in early August. I brought her to the vet to see if they had any suggestions. We did the 2 fish oil and 1 vitamin E and had a terrific coat a month later. She took first in showmanship.
Had a similar situation with mast cell tumor removal and hair not growing back well. My vet suggested Melatonin which worked very well. I gave her one capsule daily for a few weeks with good results.