I have a 2 yr. old hen who has been doing the gape open mouth thing occasionally for the past couple months. I discovered a mite infestation so I dusted my birds, cleaned out and Sevin-sprayed their coop, and then treated them with pour-on Eprinex (0.5 cc/bird). That was several days ago. This morning I still see this hen doing the gape mouth thing. So. Is Eprinex effective against gapeworm? I've googled but have found different opinions. I'm thinking of ordering valbazen for a second wormer dose for next week.