At a loss for poopy bottoms

[amama]

I have 2.5 yr old Cinnamon Queen hens. They are mostly free range (or were until we got a rooster that likes to keep them close to the coop).
First, I know that sometimes chickens just have messy bottoms, and some more than others. But our hens were looking great until all of a sudden seemingly they all have messy poopy bottoms. The eggs are gross, and I'm concerned about why specifically, as we're about to raise/add new chicks to the flock. I've looked them over for any sign of lice or mites, and see nothing. I have looked at their droppings, and see nothing concerning; no worms or blood. It's been about 2-3 weeks that I've been checking. If they're fine, I'm fine, but I'm worried because a few years ago, we had beautiful Ameraucanas that had no signs of anything (not even poopy butt) and we sold them because we had a predator taking them daily, and the buyer contacted me and said they had worms.
Do you think that's what is going on again? It's my understanding that I'd see some sign of poor health, or worms in the droppings if so, but I didn't before. I did dust with poultry dust, but don't like to medicate unneccesarily.
Thanks for any advice.

 

[StinkyAcres]

Sometimes worms are not visible in their poop. Try to get a fecal test done. Some non-exotic vets will do them for you.

 

[dawg53]

You dont want to wait for worms do to internal damage that's literally sucking the life out of your chickens. Worm them with Albendazole or Safeguard. As stated, gather a few droppings and put them in a ziplock bag and take them to a vet and have them look at the sample under a microscope for worm eggs. Or, skip the vet and just go ahead and worm your birds like I do.