Capillary worms are very bad, so I would think that most would worm for them even in small amounts before they get out of hand. They can cause breathing problems and crop blockages.
https://ucanr.edu/sites/poultry/files/201396.pdf
http://www.poultrydvm.com/condition/capillaria-worms
https://www.merckvetmanual.com/poultry/helminthiasis/overview-of-helminthiasis-in-poultry
https://ucanr.edu/sites/poultry/files/201396.pdf
http://www.poultrydvm.com/condition/capillaria-worms
https://www.merckvetmanual.com/poultry/helminthiasis/overview-of-helminthiasis-in-poultry