This year, I've noticed with Riley that just petting him will loosen many of his top coat guard hairs and shed them all over me. I've also noticed that these shed hairs are gray toward the folicle end. They usually fall out in the section of his back right along his backbone.

I've seen a lot of forum posts about what to do with undercoat shedding, but has anyone experienced top coat shedding? I hardly get any undercoat out of him since spring of this year.

Does it sound like a food/environment allergy? I've spoken with my vet, and she's not sure if it's food/weather/ShedStop. I've been using the ShedStop since July and worked well on the undercoat shedding. Any ideas?