Are my eggs fertilized?

[Eliese]

New to all of this. I brought some pekins and silkies from 2 seperate breeders. All the hens were in with roosters. I cracked a few eggs to see if they were fertile but cant tell. All seemed to have a faint white bullseye around the center white dot. Any help would be fantastic. ohh i should mention one of my hens is showing early signs of becoming broody.

 

[getaclue]

Ding, ding, ding....FERTILE

 

[Pork Pie]

Maybe compare them against the pics on these links

http://www.backyardchickens.com/t/16008/how-to-tell-a-fertile-vs-infertile-egg-pictures

http://horseshoe.two61.com/files/2013/04/fertile-eggs21.jpg

 

[Hybridchucks]

yep! those are fertile@

 

[getaclue]

At least 2 are clearly fertile. The other 2 are questionable, however, I think that's due to the angle, and lighting.

 

[Eliese]

Ding, ding, ding....FERTILE

If i allow my hens to keep laying (in the one box i might mention) they are not interested in the other boxes. How long can the eggs sit and remain fertilised in winter (between 6-25 degrees Celsius night and day) im hoping (fingers crossed) that they are collecting a brood before sitting on them. When my hens lay on egg they sit in the box and make funny noises and collect straw from around them placing it on their backs, but then leave the box after the egg is layed.