chicken

This is the same sign as "BIRD."

CHICKEN:

Even though this is the same sign as "BIRD" it is easily understood in context.
If you have to have a difference, you can do the "beak" sign with your right hand and hold your left flat hand palm up in front of you. Then bring the "beak" down to the left hand to represent a chicken pecking for seeds on the ground. After the tip of the beak touches the palm once, pull the beak up about three inches and down again.