Q:I think that somebody already asked about horses or maybe ponies that defecate in their water buckets. Why do some defecate onto the walls of the stall, pasting manure onto their tails, hindquarters, and all over walls? It makes a big mess that I have to clean up every day.

A:I’m not sure that all the reasons why some horses do this are known, but most likely the majority that do it have some physical, as opposed to behavioral cause. Horses with irritation of any sort of the anus or perineum, in addition to rubbing, tend to defecate against objects–walls, posts, whatever–in a manner that seems deliberate.

As far as I can find out, no one has studied why some horses smear feces onto themselves. But perhaps that just happens in the processes of rubbing the irritated part against the object while defecating.

There was a draft horse stallion that tended to defecate while backed up to a wall. When he was in the corner where his feed pan was mounted, it landed there. The back wall was covered with feces, and the feces that was deposited through the stall’s front grill to land on the ledge and onto the aisle floor in front of the stall. His groom had to clean the wall every day, and it still was dirty most of the time