Wagyu beef
Japan was effectively isolated from the rest of the world from 1635 until 1854; there was no possibility of the intromission of foreign genes to the cattle population during this time. Between  1868, the year of the Meiji Restoration, and 1887, some  foreign cattle were imported. At first, there was little interest in cross-breeding these with the native stock, but from about 1900, it became widespread. It was ceased abruptly in 1910 when it was realized that, while the cross-breeds might be larger and have better dairy qualities, their working capacity and meat quality was lower. From 1919, the various heterogeneous regional populations that resulted from this brief period of cross-breeding were registered and selected as "Improved Japanese Cattle". Four separate strains were characterised, based mainly on which type of foreign cattle had most influenced the hybrids, and were recognised as individual breeds in 1944. They are collectively known as wagyū, and are: