In the United Kingdom the Agriculture and Horticulture Development Board (AHDB) has two new genetic indexes to help farmers breed more environmentally friendly cows. The first, EnviroCow, reflects the important role genetics and breeding play in improving the environmental efficiency of milk production. Incorporating cow lifespan, milk production, fertility and the new Feed Advantage index, EnviroCow is focussing solely on breeding cows for their environmental credentials. EnviroCow expresses on a scale of about -3 to +3, where the highest positive figures are achieved by bulls which transmit the best environmental credentials to their daughters. These will be cows which are predicted to create the least GHG emissions in their lifetimes for each kilogram of solids-corrected milk they produce. Feed Advantage, incorporated in EnviroCow, helps dairy producers identify bulls with the greatest tendency to transmit good feed conversion on to their daughters. It is expressed as a Predicted Transmitting Ability (PTA) in kilograms of dry matter intake saved during each lactation. Adjustments are made for the size of the animal, as a smaller cow requires less feed than a larger cow giving the same level of milk production. The most efficient cows consume as much as 400 kilogram less in one lactation compared with the least efficient cows, meaning that for the same level of production there is substantial scope for cutting feed use, according to AHDB.