It says at UO Guide: http://www.uoguide.com/Battle_Chicken_Breeding
Obtaining an Egg
Bonded Pets
Chicken lizard will bond to their master like any other pet (after it has been fed at least once, then a second time 7 real life days later). Once the pet is bonded, on the day following the bonding, if the player feeds the chicken again, it will have a chance of laying an egg
. If the chicken doesn’t lay an egg on that first feeding, feeding it further will not yield any egg. Player will have to wait a period of time after the first feeding. The chicken will lay a maximum of 2 eggs a week.

I had a "tame" not bonded, chicken lizard drop and egg today.
Im going to tame a bunch more and see if i get eggs from them as well.. will report back.
Obtaining an Egg
Bonded Pets
Chicken lizard will bond to their master like any other pet (after it has been fed at least once, then a second time 7 real life days later). Once the pet is bonded, on the day following the bonding, if the player feeds the chicken again, it will have a chance of laying an egg


I had a "tame" not bonded, chicken lizard drop and egg today.
Im going to tame a bunch more and see if i get eggs from them as well.. will report back.