hens are 37 weeks old and still not laying

[doriss1878]

I was just wondering if anyone has had this same issue with their hens. I have an australorp, a barred rock and an easter egger that are 37 weeks old and still have not laid a single egg. They came from the same feed store. I also bought a buff orpington, 2 speckled sussex and 2 columbian wyandottes from a different store around the same time and those birds have all been laying for a few months now.
The thing that has me wondering is that the 3 non-layers have huge, bright red combs, have been squatting and sitting in the nest boxes every couple of days for at least 3 months. Any ideas what's going on?

 

[AAA Breeders]

Even though they have red combs they may suffer from some minor intestinal problems. Watching out for their poop may eliminate this scenario if their poop is just fine @doriss1878

 

[donrae]

Do they free range? Any chance they're laying elsewhere?

 

[doriss1878]

no, they are always in their coop/ run.