Mouth Ulcer

[herojn4355]

Just one thing after the other with this horse. It’s a good thing I love him!!
Found this today. Any ideas on what could have caused it?
No buttercups in the field so I’m a little stumped. Maybe just found something he’s sensitive to?
he’s just chowed his dinner down as normal so it’s not bothering him too much. Wasn’t overly happy about me holding his head to look at it but to be honest that could just because I had to faff with his mouth a lot a few months ago when he had some laser surgery. I don’t want to push the issue as I don’t want him to become shy from it if that makes sense? He turns 3 in a few days!
thanks in advance!

 

[Parrotperson]

I cant see a picture?

 

[SpotsandBays]

Can’t see a photo. Does it look like this? If yes, then it’s likely to be a summer sore (cause by a fly larvae burrowing in through the skin - gross!) My 3yr old had this a few weeks ago. Gave him a dose of an ivermectin wormer and it has cleared up now!