In doing so, they can spread disease and lower egg production.

Another possible cause of death was the complications during egg production.

This is thought to be because the female required a larger body size for egg production.

Egg production, which began in the 1920s, thrived into the 1970s.

They were hard to raise and focused primarily on egg production.

Egg production is an essential part of the female reproductive system.

At the same time, egg production was increased by scientific breeding.

By 2009 the battery cage system of egg production will be no more.

Egg production in this district is large, so transport facilities are good.

And a mystery of egg production was what signaled it.