hair loss - why?

[Vikki89]

What could cause hair loss? my horse has a bald patch and i dont know why, its not in a place where a rug could have rubbed.

 

[thedunthing]

Could it have been scratching on wall/fence?

 

[Vikki89]

i dont think so,its in the middle on his chest, above between his front legs, hard to explain. he got lice last year so was worried it might be that again but i can't see anything.

 

[treacle_beastie]

I have no idea but mine seems to have been doing a lot of self mutilating this year and has some unexplained chewed/bald patches. I thought she maybe had mites/lice too but she is not showing any other symptoms!