A method of predicting the ability of a salmon to utilise dietary pigment, the method comprising determining the alleles present at one or more DNA polymorphism in the salmon and predicting the ability of the salmon to utilise dietary pigment based on the determination of the alleles. The method may be used for selecting a salmon for use as broodstock. Also contemplated is a method of improving the ability of a salmon to utilise dietary pigment, the method including the step of administering an agent that inhibits the expression of the genes bcmo1-like and/or bcmo1 and/or an agent that inhibits the activities of the proteins Bcmo1-like and/or Bcmo1.
