Having a variety of pets is what we decided to avoid, sometimes various animals get along with each other and sometimes not -- it was either a pet dog, a cat, or some hens (no roo's are zoned here).  DH never had chickens before so we got the limited 5 hens to try out.  We've cycled through 18 chickens in 6-1/2 yrs to get down to the breeds we like.  I like sweet Ameraucana's but had a couple girls who suffered in our horried SoCal climate so I don't get heavy or full-feathered downy breeds anymore.  Love the smoother-feathered Breda and perky Dominique.  DH loves his Silkies but we're down to one left -- she's our oldest hen and kinda special.
Whenever we had new pullets, they would chase stray cats out of the yard but once they start laying eggs they get wary and don't chase the strays.  Maybe our 3 new Dominiques will eventually chase out the stray cat -- but they are only 3 months old and still in their chick stage.  We almost caught the stray Calico in the Hav-A-Hart cage since we found some of her fur caught in the door.  We'll keep trying to catch her.  I don't want to use poisoned food in case lizards, wild birds, or rodents eat it and die in the yard -- I don't want our chickens possibly eating poisoned carcasses.  I do love Calico cats -- had one on Mom's farm -- great mousers.  Just don't like people who leave their pets behind when they move away and leave us to deal with their irresponsibility.