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An F1 hybrid (or filial 1 hybrid) is the first filial generation of offspring of distinctly different parental types. F1 hybrids are used in genetics, and in selective breeding, where it may appear as F1 crossbreed. The term is sometimes written with a subscript, as F1 hybrid.
An F1B doodle is the offspring between a parent doodle and a poodle. This breeding is done to produce more hypoallergenic and non-shedding qualities in the puppies. Coats of F1Bâs are much curlier than F1âs, even to the extent of being called wool, or fleece.