The underside of a mature cap becomes filled with green fermenting food. This causes the classical smell found in young horses with caps ready to come out. The small bloody area is where the cap was still attached to the gum.

Responses

If you are a member, THANK YOU for supporting my effort of Helping Horses Thrive In A Human World™. Please forward this website to everyone you know. Membership is a way to get more from this site and also supports the maintenance and updates. Thanks, Doc T!
This is default text for notification bar