Thin shelled eggs

[richardeblack]

Hello All
Sorry to be raising another thin shell post but none of the other posts quite fit my situation.
I have 4 hens, 3 brown and one white. They are all escapees from the large free range hen breeding unit behind my property (they are massive barns rearing from very young chicks to point of lay when they are taken out to commercial free range farms) so are not intended for long lay life, about 1 year cycle of hens.
My brown ones are about 3 or 4 years old with the two oldest now laying very rarely and the 2 to 3yr old laying more regularly. The problem is that all their eggs are thin shelled and rarely make it out of the nest box. The younger white one lays every day and the eggs are strong and delicious.
They are free ranging during the day and I always have layer pellets (which have calcium added) available for them which they all eat. I have oyster shell and crushed eggshells always available. I don't really know who is laying what so don't really want to dose up a hen who isn't laying with calcium supplement.
I haven't ever wormed my hens so don't know if that causes problems? One of them has ascites which I drain periodically to keep her comfortable. All are lively and appear in good health generally.
Might it just be age (I know they aren't old but well beyond their "design" life)?
Thank you for taking time to read this.
Richard.

 

[coach723]

Age could be a contributor. Sometimes shell glands malfunction. Having said that, the only way to know if it's simply calcium deficiency, is to supplement it. It could be calcium and either they are not absorbing it as well as they used to, or something in the diet may be affecting absorption (some greens are high in oxalate and interfere with calcium absorption). You could try crating one bird at a time, in the run with the others, til she lays. See what her egg looks like. Then you can treat that one with calcium to see if it helps. And just work through them that way. If they look too much alike to be sure (once they are out of the crate), you can use colored zip ties to band their legs so you know who is who. I band like that when ever I have a question about a particular bird having something going on, so I can easily recognize them, some of my birds are pretty hard to tell apart.