Get some fresh dark greens into the chickens as a source of vitamin K. The poison likely makes for an increased need for vitamin K. Discard current bag of feed replacing it with another that is freshly made (check run date so no more than 30 days old) and supplement with a chick starter feed to increase vitamin intake. Store feed in cool, dark and dry location such as provided my a covered metal trash barrel.
Look into means other than poisons to control your rodent problem. Limiting access to feed, especially at night will be a good start. Cleaning up empty feed bags and other sites rodents use for nesting helps as well. Check into methods for drowning mice in buckets of water as they will become more effective as mice have hard time finding spilled grain. I use a limited ration that is completely consumed during day before birds go to roost which means feed applied in morning and I have to check in evening to decide whether more or less it to be applied the following day..
Look into means other than poisons to control your rodent problem. Limiting access to feed, especially at night will be a good start. Cleaning up empty feed bags and other sites rodents use for nesting helps as well. Check into methods for drowning mice in buckets of water as they will become more effective as mice have hard time finding spilled grain. I use a limited ration that is completely consumed during day before birds go to roost which means feed applied in morning and I have to check in evening to decide whether more or less it to be applied the following day..