Sephardic/Mizrahi Jewish Genetic Diseases. 1  Alpha-Thalassemia. 2  Ataxia Telangiectasia. 3  Beta-Thalassemia (B- 4 T) Corticosterone Methyloxidase Type II Deficiency.  Costeff Optic Atrophy (also known as Type III 3-methylglutaconic 1  Aciduria) Cystic Fibrosis.  Familial Mediterranean 1  Fever. Familial Tumoral Calcinosis.
They will lay best at 1 to 2 years of age. All pullets (female chicken under 1 year of age) lay small eggs at first and after a while will lay larger eggs. Younger hens will lay 1 egg every 3-4 days. A hen 30 weeks old can lay 2 eggs every 3 days.
The US Department of Agriculture reports the average hen lays about 260 eggs per year, about 5 per week. They have a lifespan of about 10 years and will usually slow egg production as they age. Many other factors can affect the bird's ability to lay, however.