Eggs with rings - should I be concerned?

[MsDarkAngelKisses]

Those are beautiful eggs !

 

[DuckyDonna]

I have runners also and they've been laying for about 2 years and in the past 6 months, I've gotten 2 blue eggs for some reason. The rest have always been white. I guess nature just decided to go blue for a minute. I do wonder what caused that to happen

 

[BornToQuack]

Thanks for the responses, everyone! Just to clarify: my ducks have always laid blue eggs. My concern is that one girl is now laying eggs with a dark band around them (before now, they were a consistent solid blue).

The band itself concerns me, because I want to be sure it's not a sign that eggs are getting temporarily stuck on their way out.

 

[BornToQuack]

@Magnolia Ducks no, I'm not hatching eggs, but my avian vet suggested that we put the girls on Mazuri Waterfowl Breeder feed. I've attached the product sheets for both their Maintenance and their Breeder feeds.

As for calcium, the Breeder feed has calcium in it, but I also give the girls free access to oyster shell at all times.