How is eggs size determined?

Egg size is mainly determined by the breed and genetics of a hen. Different breeds of hens will naturally lay eggs of different sizes, with some breeds known for producing larger eggs and some for laying smaller eggs.

Additionally, the age and health of a hen can also influence egg size. Younger hens typically lay smaller eggs, while older hens tend to lay larger eggs. Factors like nutrition, diet quality, and stress levels can also play a role in egg size.

However, it's worth noting that while breed and age play a significant role, there can also be variations in egg size within the same breed and age group due to individual bird differences and other environmental factors.