A chicken owner recently asked David Sullenberger, also known as Professor Chicken, www.professorchicken.com, what could be causing occasional weak shells in her seven-year-old Australorp's eggs.
"She is still laying every day whereas others her age seem to be laying every other day," she explained.
He advised her to get a good rooster with her and hatch some chicks to perpetuate the strong genes that make her such an excellent layer. Most chickens stop laying daily after the age of three years. They will continue to lay, with production gradually declining. At age seven, few hens are laying even three eggs a week. So this formidable chicken is to be honored for her success!
As chickens age, they are less efficient in digesting food and absorbing nutrients. Thus, her body isn't able to make egg shells as strong as when she was younger. However, making sure she and her sisters are getting sufficient calcium and phosphorus in their diet, through free-choice oyster shell or other supplement, is worth ascertaining.
Australorps are an Australian variation of English Orpingtons, developed for egg production. They are black, as shown in this illustration from Welp Hatchery in Bancroft, Iowa, www.welphatchery.com.