OK, Im going to say this once again
then Ill have to leave this topic, theres a little too much dictating going on for my comfort.
I understand why people are reluctant to use rat poison, I share that reluctance but it IS possible to use poisons responsibly even if you have pets and children and chickens.
If you have a rat colony established in or around your coop/barn/yard, you have a real problem. As has been mentioned, if you see a few, you probably have a few hundred. They spread disease, parasites, bugs and can kill or injure chickens, young or old, and theyll raid eggs and steal huge amounts of feed from you and your chickens.
Theyre smart and tenacious and traps are not always very effective after a time because they do learn very well.
First clean your barn, eliminate all feed sources you can, clean up all stray edible things and make sure your feed is stored in rat-proof containers and even stop feeding free-choice for a time while you work to get things under control.
Get your coop as rat proof as possible, but its not always possible, so do your best.
Then, go shopping for bait stations that animals other than rats cannot get into
also, look for the right kind of poison.
There are two types, Multi-feed and Single-feed poisons.
First is the multi-feed type, the main chemical in that is either warfarin or coumatetralyl. A rat must eat these types of baits over several days to become affected by them, this means that pets and wildlife are less at risk because they either have to consume a large quantity of bait in one sitting or consume small quantities of bait over a long period. (if its safely in a bait station or protected area, they cannot get large quantities at one time)
This means that even if your dog or cat does get a dead or dying rat and eat it, there is little in the stomach to hurt them, and since its not terribly potent and its only the poison in the rats stomach that hurts your pet, not what's already been metabolized.
Single feed poisons are MUCH stronger and act more quickly. These rat baits are more toxic to rats and pets and a single dose is more likely to cause poisoning. Single feed poisons are those containing brodifacoum (e.g.Talon) and bromadialone (e.g.Bromakil).
BOTH the single and multiple feed types are commonly available from local supermarkets and hardware stores etc. Brodifacoum is at least 40 times more potent than warfarin and is much more likely to cause the death of a rat, a pet or a wild animal with a single feed. Secondary poisoning is also more likely to occur because a rat can have enough bait in its stomach to poison at least a small dog or a cat, sicken a large one.
This is why the single-feed poison which is so much stronger and kills in one shot is more dangerous. The rat or mouse usually dies with more un-digested in their stomach, and so it's available for a pet or wildlife to ingest if they eat a dead rat.
Either way, you need to be aware of your pets and control them if/when you do set out poison. Control them more carefully than usual when trying to get rid of a rat infestation, and certainly toddlers etc, but if you really have a bad enough rat infestation, poisons may be a tool to consider, just make sure you think it through. You need to put it either well down into the actual tunnels/holes or in bait stations and/or protected areas that your chickens and pets cannot get to.