Depends what animals you have , dogs should be done at least spring and fall, (after freeze up), but monthly during warm season is fine, oral dewormers don’t harm them at all. I do the chickens once a year in the fall, you have to get rid of eggs for ten days or so but the girls are usually...
Hahaha yep they love it...dry crunchy ones, fresh stinky ones, frozen ones they pick up and play with, yuck!
I just deworm everyone regularly and don’t worry about it.