If these infections are caused by yeast, you can use 1/2 apple cider vinegar to 1/2 warm water and use to clean the ears. Sounds like it also could be caused by the long eared conformation of the Cocker, where yeast like to flourish in the warm moist ear of a drop eared dog. IMO, you should take pup to the vet, perhaps she needs a round of antibiotics and an ear flush. The ACV solution has worked with my Bullmastiff, also a change in diet to a grain free, I'm not sure which is making the difference...but I'm not changing anything! Also, getting some air into the ear canal might help. You might want to devise a way to tie those long ears up for part of the day...hopefully she won't mind and will tolerate that!
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