F1 refers to a first generation cross between two purebred animals. Only if that cross was repeated and the resulting offspring bred back to similar animals until it had its own "identity" with a written set of standards would it become a "breed"
> What is the genetic make-up of the
> F1 breed?... The F-1 is not a breed but rather a composite, a f-1 is a term for a first generation crossbred, in the south the term F-1 is usually applied to a Brahman-Hereford cross which is an excellent cow which far excells the parent breeds in performance due to the high amount of hybrid vigor produced from a bos indicusxtaurus cross. Hope this helps