Probiotics yes, first thing as chicks, then occasionally through adulthood.Should chicken owners automatically deworm and give probiotics no matter if you think they have a problem or not, just to be on the safe side? The more I'm reading on worms and fly strike it makes me nervous to just not do anything for them.
With worming my opinion is not to treat unless you see the worms in the poo, or have had a sample test positive at the vet. Some owners treat for worms as a preventative.
Best prevention is to keep their house cleaned of poo daily, give them plenty of area to roam, fresh water at all times, and keep an eye on their backends, as well as their entire body.