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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: The F stands for filial generation. F1 means first generation and is a common scientific term. This, in the Labradoodle breed, is the coding for first-cross, purebred poodle to purebred Labrador Retriever. The results are mixed, as this is not the breeding of two like dogs, or dogs that resemble each other. F1 Labradoodles typically are moderate- to low- shedding and have a sparse-hair to fleece coat.