is it? then why there such thing as Australia Wagyu and US Wagyu?
http://www.uidaho.edu/uirp/tenants/americanwagyu
http://wagyu.une.edu.au/

wagyu is wagyu, unless u r saying american wagyu and australian wagyu is lack of standard as japanese ones.

So what do I get when buy Wagyu in the U.S.? Unfortunately, the term has little if any precise definition in this country. Honest to goodness full-blooded cattle from different Japanese or Wagyu breeds have been exported to this country in the past for breeding, before the ban. Some well-intentioned farmers have maintained these bloodlines in 100% pure forms, with the documentation to proceve it, and these would be the ones to seek out. But most have not. Even the term Purebred Wagyu, used by the American Wagyu Association, does not refer to a wholly pure animal. Their term for that is 100% Wagyu. However much of what is sold as Wagyu here is what the AWA calls “percentage Wagyu” meaning it is part Japanese breed after being crossed with other types of cattle. In some cases, the “purity” of the Wagyu line goes back two generations, and the percentage Wagyu is the grandchildren of the Wagyu after cross-breeding. So the products sold under the Wagyu name in the U.S. vary widely. Also, these terms, 100% Wagyu, Purebred Wagyu, and Percentage Wagyu are constructs of the AWA, a trade group, for marketing purposes, not legal definitions. When you see Wagyu, it might be 100% of a Japanese breed, like that used for Kobe beef, or it might be much less. Unless you are in direct contact with the breeder, it can be impossible to ascertain either the breed or the Wagyu content.