Again vets vets vet, but if you want some friendly advice and you can wait a day then read below.
The interdigital cyst is a strange one as they come and go in a day. You may notice your dog is limping slightly and when you look between the toes is a swollen area. The very best treatment for these is Epsom salts in nice hot water. Not hot to scold the foot but hot to soak the skin. Do a daily bath or twice daily after walking in muddy ground.
These can be seen on any dog breed and cross breeds. I have read articles where they think (and I use the word think as no-one really knows), it could be down to a weakened immune system. I have a male Pug who is healthy as can be, but if he trots around in muddy conditions he will get a swollen interdigital cyst. So I wash his foot, Do not squeeze it, and I know its tempting but leave alone. Then dip in dissolved epsom salts in hot water. Its gone by the next day. Feet are great places for yeast growth, bacteria and I always say smell the feet to know whats going on. If they don't smell then the foot is healthy. If the foot smells of biscuits then its probably yeast.
If the swelling has not gone down in a day even after using epsom salts, then ring your vets for a consultation to make sure its nothing more than an interdigital cysts. Sometimes it can be a grass seed which needs surgical removing. Grasses can go into the skin and then work their way up into the skin. Also checking the dog doesn't have a small tumour.
Yeasty feet is something completely different which I will talk about on another day. Most commonly yeasty feet is to do with food allergy or even allergy in the home environment.
Mrs Rachel Savage