Basemesh of your horse is very cool. but I think here is a bit problem in nose part. the nose is looking rounded but it is different in reality. and the butts are too broad they should be in proportion.
I have some images of Horse anatomy I think it will be helpful.
and your online blog is really very cool. all of your creations are awesome. I like the male and female most but the abs of male are looking too sharp.
Keep good work dude..