Oncorhynchus mykiss
Rainbow trout are commercially farmed in many countries throughout the world. The practice began in the late 19th century, and since the 1950s commercial production has grown dramatically. Worldwide, in 2007, of farmed rainbow trout were harvested with a value of about US$2.6 billion. The largest producer is Chile. In Chile and Norway, sea cage production of steelhead has expanded to supply export markets. Inland production of rainbow trout to supply domestic markets has increased in countries such as Italy, France, Germany, Denmark and Spain. Other significant trout-producing countries include the U.S., Iran, the United Kingdom, and Lesotho. While the U.S. rainbow trout industry as a whole is viewed as ecologically responsible, trout raised elsewhere are not necessarily farmed with the same methods.