Originating in Japan, the Wagyu breed has expanded to more than 25 countries worldwide. Since the first exports from Japan in 1976, Wagyu has captured the imagination of beef producers and consumers alike for its extraordinary flavor, eating qualities, and health benefits.
Understanding the Wagyu breed begins at their initial evolution away from more traditional breeds of cattle. The Wagyu breed was not originally selected for agricultural purposes but for work, rather than as a food source (Hirooka, 2014). This allowed for a different marbling pattern to emerge, which is what the Wagyu breed is known for today. These marbled cattle are highly sought after, as the taste and tenderness of Wagyu is unlike other breed of cattle. In addition to their superior meat quality traits, Wagyu also possess favorable expression of calving ease and longevity. The Wagyu breed increasingly plays a vital role in global beef production by providing a genetic makeup recognized for their exceptional fitness and premium carcass characteristics no other beef breed can offer.
The Wagyu breed has been subject to regional isolation due to Japan’s geography, which led to three black and two red strains of Wagyu to emerge. The three black stains, Tajiri (or Tajima), the Fujiyoshi (or Shimane) and the Tottori (or Kedaka) are traditionally known for their excellent meat quality and superior marbling with average to moderate growth rates. The red strains, Kochi and Kumamoto, are still high quality animals, but have a strong Korean and European breed influence.
The Wagyu breed has now expanded to more than 25 countries, each having their own Wagyu population and specific breeding program. All have utilized the marbled cattle to achieve highly graded cuts of beef. Yet, breeding Wagyu while also keeping in mind the smaller genotypic pool that is available. This population of animals underwent a genetic bottleneck outside of Japan due to the limited number of exports since the 1970s (Jussaume et. al., 2020).
Wagyu breeding practices should focus on keeping a lower inbreeding coefficient while maintaining a strong selection for the highest levels of marbling. Future selection decisions should put an emphasis on quick marbling while keeping the fine ticked marbling pattern, consider the composition of fatty acids, and to keep focus on the environmental effects that are at play.