I forgot where I read it(but I printed out a list) but there are a tons of herbs that help with different chicken ailments. it said to line their nests with the herbs to help the eggs, chicks, and hens, and they don't even have to eat it if they don't want to, and non of it is harmful. But rosemary was said to help with minor pain, respitory problems, and is an insecticide. other insecticidal herbs are catnip(and sedative), lavender(and helps with stress), mint(also rodent repellant), nasturtium(helps with laying, is a mild antiseptic, antiboitic, and wormer also!), peppermint(anti parasite too), and spearmint(antiseptic, and stimulates nerve, brain, and blood!)