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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.
F1 Labradoodle - this is the term used for the first crossing of a Standard Poodle with a Labrador Retriever. Their coats can vary greatly and are almost always going to have some shedding. F1 = Labrador Retriever x Poodle. F1B = F1 Labradoodle x Poodle. Labradoodle to Labradoodle. F2 = F1 x F1.