Bald patches

[hairycob]

Bobby has developed some bald patches. They have come up since he was last ridden 2 days ago. The biggest is just behind his rib cage & is about the size of my palm. Not itchy, raw or weepy, just no hair. Can't see any bugs.

Theories so far are:
1) too warm in rug making him itch. He has a v thick coat & rug is just to keep him clean.
2) irritated by bots - we are still getting fresh bot eggs, even this week.

BUT biggest bald spot isn't in an obvious rubbing spot

3) New ponies in field, may have bitten rug & grabbed hairs with it - but biggest patch is where rug is loose.

4) he has already started moulting so maybe some old coat has come out too soon.

Have sprayed with iodine & plan is to watch & if it spreads, gets sore looking to call vet.
Any other ideas?

 

[chestnut cob]

Is he changing his coat? Mine gets bald spots when he changes his coat in autumn and winter/spring. The only thing that stops it is clipping as he starts to change his coat.

 

[hairycob]

Yep, he starts to shed his coat as soon as Christmas is over. It's so thick it takes until after Easter to go. I've got my fingers crissed it's just chunks that have come out before the new coat is through. Last year he looked a bit moth eaten for a few weeks, but the chunks that were coming out had v short hair underneath. This is just skin.

 

[chestnut cob]

Mine horses' hair used to come out in great chunks leaving just skin underneath, I thought he had ring worm or something like that to begin with!