Yesterday I was giving my horse a bath and wet down her tail, as I started to look at the tail I noticed what felt like burrs around the end of the tailbone. I started to look at it when a chunk of scab/skin came off about 1 inch by 1 inch and there was a bloody raised nodule about .5in high and .5in wide underneath where the scab was and the skin around it was very bright. I started looking closer and there was another one identical to it on the underside of her tail, there are no other ones on her tail or her body that I saw. The nodules were like an abscess that is soft and squishy and seemed to be fluid filled possibly. When the second chunk of hair came off there was yellow pus underneath the scab/skin that came off.