Hi, I'm Dr. Jill. Unfortunately there is little that can be done at this point aside from surgery to remove the popsicle stick...which would definitely not be in his best interest unless he becomes ill. On the bright side, I wouldn't expect this to cause him any problems. There is a slight chance that the stick could cause damage to the intestine or assist in causing a blockage, but I think the risk of either of these occuring is very low. Popsicle sticks are relatively small and are very rounded...so hopefully no sharp edges to cause problems.

You can keep an eye on his feces...you may see the popsicle stick in a day or two. And if you notice a significant change in fecal consistency or output, or any signs of abdominal pain, it would be time to consider an evaluation by your veterinarian. You could also have your veterinarian give him a dose of mineral oil via a stomach tube to try to coat his intestines and lubricate the popsicle stick, but if it were my horse I would just keep an eye on them as usual.

If you have any additional questions or concerns, please let me know. Thanks!