Darkgreen cock split opaline and blue x opaline hen split blue

The facts

Sire: darkgreen cock/opaline, blue
Dame: lightgreen hen/blue

Not all of these will happen with the same probability, but I will not go into that for the moment.

Analysis

There is one unexpected factors in our offspring: fallow

Fallow

Fallow, as so many factors is recessive, meaning that both parents must have the factor in order to breed one. This means that both parents must be split:
Sire: darkgreen cock/opaline, blue, fallow
Dame: lightgreen opaline hen/blue, fallow

Conclusion

Sire: darkgreen cock/opaline, blue, fallow
Dame: lightgreen opaline hen/blue, fallow

Expected offspring
  This will be the same as the original (represented with ....) with the possible addition of being split fallow or fallow:

(x2) means twice as probale as the other lines.

(C) Bert Raeymaekers