By definition hybrid vigor or heterosis exists when the superiority of the crossbred offspring is better than the average of its parental breeds. It is a free boost in production because of the combination of genes the crossbred offspring has. It is caused by a certain type of gene action. The amount of hybrid vigor that is expressed will differ from one trait or characteristic to another. For example those traits associated with fertility, general well-being and health tend to show more evidence of hybrid vigor in the crossbred that traits associated with production such as milk yield, or product such as carcass characteristics. In commercial livestock (including goats) product production the systematic use of hybrid vigor is recommended. The most advantageous situation is when the crossbred offspring produce at a higher level that the best parental breed; therein lies the real advantage of hybrid vigor.