There are many problems that can occur with keeping poultry be it just smells in the soil or the more serious disease outbreak, each problem no matter how small must be addressed as soon as it occurs, If not a small problem can soon become a huge problem.
Vermin have to be a big concern when keeping poultry if left alone a small vermin problem can soon become a massive infestation, but with solving the problem can bring in its own problems for yourself and your birds if not dealt with correctly.
Rats will always be around if there are poultry because there is always some left over feed, you can deter them by not leaving feed out over night or feeding off of the ground, but chickens being what they are, are messy eaters, getting into their feed bowls and kicking feed all over the place, to the rats and mice this is heaven
So how do we control them? traps have to be the safest option, but so that they are out of the way of the birds, a rat trap won't mind if its a rat or a chicken in there! We use the old fashioned snap traps and what i do is i build a wooden box around each one just big enough for the trap to fit inside, that way the chickens cant get to the bait but any rat or mouse will set it off when it wonders inside. there are loads on the market, from live catch traps to some that look like they have come straight from a medieval torture chamber.
Poison is something that I try to avoid, but sometimes it becomes necessary to lace some down, if this is the case I use something called D-RAT, it comes in a liquid form and you have to mix it (very carefully) yourself to grain, I used this because it is the fastest acting poison. If you use poison, then as far away from the birds as possible, remember that it is always added to grain or pellets and our chooks love both, Also I must add that if you do use poison, go around every morning and pick up any dead rats or mice that there are, your chickens love to eat mice and if they eat a poisoned one it will kill them.
So apart from the vermin there are a few things to look out for :-