The Japanese Black Wagyu breed has many prefectural sub populations. The three major sub populations recognized outside of Japan today are Tajiri/ Tajima (Hyogo Prefecture), Fujiyoshi/ Shimane (Shimane prefecture), and Kedaka/ Tottori (Tottori prefecture). The other sub populations represented outside of Japan today include Itozakura, Okayama, and Hiroshima.
Tajima genetics come from the Hyogo prefecture, they are among the most well-known and widely utilized strains outside of Japan. The Australian Wagyu Association calculated the average fullblood Black Wagyu to be 53.6% Tajima in 2020. Hyogo prefecture is the only area that remains strictly a closed herd in Japan today. Tajima (Hyogo prefecture) genetics are the foundation of the world-famous Kobe branded beef company. Tajima bloodline genetics have been bred specifically for marbling and carcass traits, this combined with having a closed herd contribute to a high inbreeding coefficient in many of these cattle. Tajima sire bloodlines outside Japan can be broken down into three sub strains known as the Nakadoi, Kumanami, and Okudoi bloodlines. Nakadoi genetics available outside Japan predominantly come from just two sires. First is Yasumi Doi who is the sire of Monjiro, Dai 2 Yasutsuru Doi, and Yasutani Doi. Yasumi Doi genetics can be found in foundation sires Fukutsuru 068, Michifuku, Haruki 2, TF 146, Yasufuku Jr, and more. The other major Nakadoi sire is Kikunori Doi, the sire of Kikuyasu Doi, Mt Fuji, and Kikuteru Doi. These genetics can be found in foundation sires JVP Kikuyasu 400, Mt Fuji, Terutani TF40, Kikuterushige TF150, and Westholme’s Kikateruyasudoi 003. The second major Tajima strain is Kumanami, the best-known sire from this line is Shigekanenami the sire of Shigeshigenami. His close descendants include TF 148 Itoshigenami and Okutani. The last major strain is the Okudoi line. The only exported animal with these bloodlines was TF Kinu 1, through the sire Shiroasa. The heavy focus on marbling bred into these Tajima bloodlines is what makes them the predominant source for cross breeding genetics outside Japan.
Shimane genetics logically are from the Shimane prefecture and are one of the three largest populations in Japan today along with Tajima and Kedaka. This strain is also commonly referred to by as Fujiyoshi. According to the Australian Wagyu Association the average registered Wagyu outside of Japan is 5.1% Shimane. These animals are commonly characterized as medium framed with excellent maternal traits along with good growth and meat quality. The main source of Shimane genetics outside of the Japan come from the Takeda Farms shipments. Many high Shimane females were exported by Mr Shogo Takeda, these females were characterized by strong top lines with superior maternal traits. Sires carrying Shimane genetics with influence outside of Japan include TF 149 Mitsuhikokura, World K’s Haruki 2, Kitaguni 7-8, and Itomichi. It is important to note that Shimane genetics play an important role in creating the now extremely influential Itozakura bloodline.
Kedaka genetics descend from the Tottori prefecture in Japan. This population has dominated the Japanese genetics and beef production scenes in recent decades. These cattle are known for superior growth and yield while maintaining high marble scores in Japan. The Tottori line can be divided into two major strains the Kedaka and Eikou strains. The Australian Wagyu Association reported the average fullblood Wagyu outside Japan to be 7.6% Kedaka and 3.3% Tottori in 2020. The sire Eikou J512 is the founding sire of the Tottori strain and his great grandson Kedaka J721 born in 1959 was so successful and influential that he created his own strain of Tottori genetics named after himself, Kedaka. The Westholme import group represents the only significant source of Tottori and Kedaka genetics outside of Japan. Influential Tottori/Kedaka sires outside of Japan include Madza, Kensei, Hirashigetayasu, Itomoritaka, and Shigefuku. The Westholme group imported many high Tottori/Kedaka females including Hatsuhi, Umeko, Yoshie, Sekitorihana 5, and more. Tottori/Kedaka genetics represent a key outcross fullblood Wagyu genetics resource with extreme potential.
The Itozakura bloodline modern development founded on the Japanese sire Dai 7 Itozakura. Dai 7 Itozakura was bred in the Shimane prefecture and is a combination of Hyogo and Okayama genetics. This bloodline is the second most prominent outside off Japan, comprising 16.2% of the average Wagyu according the Australian Wagyu Association. The Takeda Farms import groups represent a large source of these genetics outside Japan. Influential sires carrying Itozakura blood include Itomichi, Kitaguni 7-8, Itohana, TF 149, TF 151, and TF 147. Many high Itozakura females were imported from Japan including prominent Takeda Farms and Westholme donors. This line is characterized by a combination of strong growth and carcass quality traits.
The remaining prefectural lines outside of Japan are Okayama and Hiroshima. They represent 6.8% and 2% of the average Wagyu respectively. Okayama genetics can be found through the sire Dai 7 Itozakura and his Okayama roots as well as though the sire JVP Hiratafuji 402. The Westholme imports included high Okayama females Sawafuji 6 and Yoshifuji 8. These lines have the potential to contribute many of the same upsides of Itozakura line cattle.