[Nirvana]

Every single incidence of mad cow in the US [there were 2] was traced back to DAIRY cattle that came from Canada and Mexico.

Grass fed beef is a marketing ploy in the US. Grass fed beef cannot be graded choice or prime. It does not taste good.

Angus beef is the only beef proven to have a "tenderness gene" [ I don't raise purebreds.] I raise club calves, they are the standard for the beef industry they are composite cattle [ crossbreeds] so I don't agree with your breed theory from that stand point. You are however comparing bos tarsus to bos indicus and the cattle you speak of are a need to have in certain climates because of weather conditions and insects. The cattle raised in hotter climates are not the primary source of prime beef in the US unless they are crossbred.