Yes, but i still like them wormed before laying.
I worm peafowl before laying season and after late Aug.
Now sure thats what kill your pheasants. Few Diseases do the same, they go light.
Now eating and losing weight is one sign of heavy worm infection.
But bleach the pen, in case it was...
all looks good except july ivomec, it will affect the eggs if they are still laying, I use it 30 days before laying season. and after they stop laying. About late Aug.