I reported it via the report icon in the upper right hand corner of the post... which is probably the most quick way to bring it to the mods' attention. Sometimes posts in here don't get a reply for a few days.
You really don't want to know. It was NOT horse related though. Someone created and account and posted a picture as their first post. I thought we couldn't post pics on here though. People always post links. Either way it was big and bad. A troll to the highest degree.
If you really are morbidly curious I can tell you if you PM me...but I can assure you, you don't want to know.