The death of a Newfoundland pony last week was tragic and entirely preventable, says the west coast breeder who’s still grieving the loss.

The 11-year-old mare was apparently fed too much by people passing the pasture where Dwyer’s Little Catalina, or “Cat” for short, was grazing with other animals.

Jess Boyd, a vet herself, says the sheer number of partially eaten apples around the lethargic horse last Thursday was the first sign of trouble.

Boyd says the pony’s condition quickly worsened from there.

She says the animal was exhibiting distressing behavior, including grinding her teeth, kicking at her belly, violently throwing herself to the ground and rolling around in obvious pain.

Boyd believes by the time she realized there was something seriously wrong, it was too late to save the animal and she had to be put down.

She says it’s a hard reminder for people to avoid feeding animals that are not yours—wild or domesticated.