Burps are the top source of methane emissions from cattle. The company this spring began marketing semen with the methane trait in 80 countries. Selecting for the low methane trait could lock in lower and lower emissions for successive generations, she said. Semex is not initially charging extra for the methane trait, said Michael Lohuis, Semex's vice-president of research and innovation. Juha Nousiainen, senior vice-president at Valio, a Finnish dairy, warned that breeding cattle to burp less methane could create digestive problems.

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Persons: Nathan Frandino, Loewith's, Loewith, Drew Sloan, Frank Mitloehner, University of California Davis, Mitloehner, Lactanet, Christine Baes, Baes, Michael Lohuis, Burger, Lohuis, Juha Nousiainen, Rod Nickel, Caroline Stauffer, Suzanne Goldenberg Organizations: Johann, REUTERS, University of California, University of Guelph, University of Alberta, biosciences, Canadian, Ottawa, Nestle, Burger King, Restaurant Brands, Thomson Locations: Fresno , California, U.S, WINNIPEG , Manitoba, Lynden , Ontario, Semex, Britain, US, Slovakia, United States, New Zealand, Valio, Winnipeg , Manitoba