THE 1920S
Living outside presented some problems, mainly with weather and predators. Diseases were also a problem and selective breeding helped to cultivate healthy flocks. Hatcheries chose the strongest, healthiest birds and passed along favorable genetic factors, such as disease resistance. Special medicines were developed to help combat parasites, such as leg mites.
While these advances helped, the hens were laying only about 150 eggs a year and had a mortality rate of about 40%.