Savannah History history
As Savannahs are produced by crossbreeding servals and domestic cats, each generation of Savannahs is marked with a filial number. For example, the cats produced directly from a Serval/domestic cat cross are the F1 generation, and they are typically 50% serval (although if you use a F1 Savannah as the domestic cat, the percentage of serval blood can jump to 75%). The F2 generation, which has a serval grandparent and is the offspring of the F1 generation, is 25% serval. The F3 generation has a serval great grandparent, and is 12.5% serval. They can be very expensive to purchase because of their scarcity.
Male Savannah cats are typically sterile until the F5 generation or so, although the females are fertile from the F1 generation and on.