Have hybrid layers changed much in 40 years

[Devil's advocate]

40 years since I kept 36 hybid layers.

At the timer Shaver 585's, Warren Sl's & Thornbers were popular oh & Babcocks. 285 eggs per annum was the target, I got less because I did not have lighting & the beggars eventually learnt to eat the eggs.

Visually they look similar now, egg colour is much improved have the breeders increased production in the last 40 years.

 

[R J]

Benchmark for layers would be 330 eggs now,
Production has come on fair bit

 

[Devil's advocate]

So what hybrids are used in large scale free range?

Also are the birds kept for longer than if say they were housed in cages?

 

[Big Hoss]

72 weeks to 80 weeks of age before depletion on free range sites.
Hy-Line, Lohmann, Shaver, Warren, ISA, Bovan, Dekalb, Novogen are the main strains in the UK.
Benchmark of 325 eggs as a minimum these days. Arguably whats more important is feed consumption and consistency/persistence of laying large eggs, given the price difference between medium and large eggs.