If he doesn't have flaky skin, and isn't scratching the area, it may be his molting is very extreme. Keep an eye on it, the hair should start growing in soon. If it doesn't, other possible causes are over grooming by a bonded mate, and hormonal imbalance.
You didn't apply Revolution to that area did you ? I have seen buns who were treated for mites lose hair at the site the Revolution was applied.
If it is a molt it is odd looking but you are right that the skin looks pink, clean and healthy
Thanks for all the replies !!
angieluv - nothing was applied because nothing is wrong with him.
FreezeNkody - yep only the one.
Ive noticed its getting quite a bit worse then the photo, he is grooming a lot but he cant really reach his neck which I find wierd.
Im so happy that I recieved responses
That is exactly the spot where fur mites usually start, so keep an eye out for dry flaky skin and/or the hair not growing back. It could just be a bad shed, but it could be mites.
Hey there. My female bunny Lucy had the same problem last year. We took her to the vets to get a mite test done under the microscope and she was all clear. She had a few bald patches large if not larger than the one I can see on your picture and the fur grew back just like normal.
The vet said sometimes this happens and isnt harmful to your rabbit at all. He just said expect to see more bald patches, and keep checking them to make sure the skin doesnt become dry or inflamed! Im sure your buns fur will grow back soon enough My girl Lucy now has her full coat of fur and has had no bald patches since It only took a couple of weeks for her bald patches to disappear.
Thanks louladoll! The only difference is my bunny had this for quite some time and it just seems to get a little bit worse every so weeks. but since his skin looks good I feel reasurred