Hi. I am wondering if I can use this: http://www.firststatevetsupply.com/store2/wormers/safeguard-crumbles.html for worming my poultry. I think you put it in their food? For the past few days, some of my chickens have been sneezing a little and one had a respiratory problem. I gave her Vet Rx and it seemed to clear up mostly. I am wondering if they have gape worm? A few weeks ago I saw one of my ducks opening her mouth wide at meal time, but the next morning she seemed fine after that. Tonight, my rooster was opening his mouth at meal time, but it might have been because they had food in their throat. If I give them this wormer, will it hurt them if they don't have worms? Thanks!