The CSIRO are working on the methane belching by cows and it looks like a breakthrough is coming in a couple of years.
But in a couple of decades, if the planet isn't under rising seas--- substitute beef will be grown from either beef muscle stem cells or plant based components.
There won't be any economic reasons for growing and killing farm livestock
Of course there is no real need to grow ruminants at the moment as there are plenty of great substitutes like Kangaroo and climate change deniers for us to eat!
