Don't forget that the yellow pigmentation fades as the bird lays her eggs, so if your hen has extremely yellow legs, then she still owes you some eggs.

Here's an extract from an article ( wott I wrote

) on trap nesting and culling".
Some breeds carry a strong yellow pigment as a breed characteristic. It manifests itself in their skin, beak and in their legs. These breeds include Leghorns, Wyandottes and Rhode Island Reds. At the beginning of the laying season, this pigment is clear to see. It will also be seen around the vent area.
When laying begins, the pigment which is obtained from maize and green plants , will now be required for the yolks of the eggs. As more and more eggs are layed by the bird, the pigment is drawn on to a greater extent and the yellow colour will begin to fade or bleach out. The first colour to go, is that around the vent. The colour in the legs is always the last to go. When laying ceases, the colour will return as the bird replenishes the pigment. Pale skin colour in a yellow skinned breed denotes previous or current egg production. The area around the vent for instance tends to be completely bleached out at around two weeks into full lay. The pigmentation on a bird in full lay will obviously stay longer and stronger on a bird that is being fed yellow maize and is being given access to a grass run. These factors must be taken into account before culling commences using this pointer.