When we need to breed less cattle, the effect on the environment is huge. Less forests will be slashed to convert into pastures, less resources like fuel, gas, soil, water, grains etc will be needed to feed and service the greater live stock. According to the FAO, about 60% of the world’s agricultural land is used for grazing almost 400 million cattle and 600 million smaller ruminants.
Live stock produces lots of contaminants as ammonia, and the globally affecting greenhouse gases as Carbon Dioxide, Methane and Nitrous Oxide, contributing to global warming. Methane is some 23 times as aggressive as Carbon Dioxide. Not to speak of a secondary pollution by pesticides used on livestock.