Advice about puzzling bunny illness

Hi everybody.
This thread is not actually for one of my own bunny but for a colleague's bun.
Shortly, she got two buns (nethies) from a breeder (to my dismay as I had been talking at length about rescue buns, but that is another story...).
One of them is entirely fine, but her little buddy is having quite a few health scares. I suspect that she got given the runt of a litter as he is rather small and hardly put on weight compare to his girlfriend.
The main issue though is that a few weeks ago, he started developping some bald patches on the top of his head and on his chin. He got brought to the vet (good vet for bunnies) and she diagnosed it as possibly some type of mites/mange. He then got some ivermectin. After the first injection, it seemed to get better, i.e. some fur was starting to grow back. Unfortunately, it appears that the bald patches are coming back, even though the treatment is still ongoing but to no effect anymore. The vet did some scrapes to check if she could see any crawlies, but cannot detect anything, and is a bit puzzled at what it could be.

The main concern is that nothing seems to clear that and he now constantly has some little scabs, he also might have been loosing a bit of weight these last few days. It does not seem contagious as his girlfriend is entirely fine.
So does anybody have any idea what it could be?

I am a bit worried as they are going away at the beginning of April for a few weeks and I somehow accepted to look after them for the whole of April!
I wouldn't want any type of desease spreading to any of my buns/fosters, mostly with the new foster babes, nor need anymore worry right now.
I am getting all very stressed, need to start yoga!!

Thanks for any ideas

Two possibilities that spring to mind are ringworm and overgrooming by a mate. Has the vet done a fungal culture? Stress can sometimes cause baldness too.

Are the scabs near the eyes/mouth ?

The ringworm could be a possibility. I am not sure about any fungal culture done. But would the vet not have recognised it or seen anything on the samples taken? Might be worth a check though my main worry now is that it can be quite contagious, can't it?
I don't think it is overgrooming as she told me that his girly tends to be more of a bully, but that could hence be some stress related problems.
The main scabs are under his lower lip, saw it last time and it made me feel very sad for the poor little lad.

Thanks for these thoughts

There's a few possibilities in this article
http://www.bio.miami.edu/hare/furloss.html

I was going to suggest ringworm as well, also worth bearing in mind it can be passed to humans if that is the case.

not strictly the same - but one of our mice had this problem. No mites etc were found - it was put down to a hormone imbalance, a bit like an OCD washing themselves as a comfort.

linzi1loveanimals said:

not strictly the same - but one of our mice had this problem. No mites etc were found - it was put down to a hormone imbalance, a bit like an OCD washing themselves as a comfort.

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My bun had this problem. He developed a big bald patch on his neck after his first trip to the vet for his injection. No mites were found, the vet thought it was a reaction to the vaccine, a stress related or an over grooming problem. There was no signs of this growing back at all, he had this bald patch for abut 4 months. Then, after he was neutered the fur suddenly started to grow back , its coming in lovely! The vet now thinks it could have been hormone related.

If it's anything like vets diagnosing fungal infections in guinea pigs, they hardly ever do, and always think it is mites. I'd therefore suspect fungal too.

Aside fungic, acarian or bacterial origin, on some french rabbit forum I go to there are a few cases of rabbits losing spots of hair due to stress or a change of environment.. but a biopsy of the skin is necessary to be on the safe side of what causes it ; hormons also can play a role

:wave: sophie. No advice other than what people have already put but hope bunny get's better.

ecudc said:

:wave: sophie. No advice other than what people have already put but hope bunny get's better.

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Thanks, I really hope little bun gets better too, I would like to be able to help sorting that before they both come to mine, as I am going to be a pack of nerves. Thinking that all the buns are going to get whatever it is!! I do think that the option of ringworm or stress could be it. We'll see what's the news next week.