Livestock produce methane through enteric fermentation and release it through eructation. Increased demand for a meat-based diet is a large contributor for climate change.
Livestock are domesticated animals raised in an agricultural setting to produce commodities such as food, fiber and labor. This article does not discuss poultry or farmed fish, although these, especially poultry, are commonly included within the meaning of livestock. Livestock are generally raised for profit. Raising animals (animal husbandry) is a component of modern agriculture. It has been practiced in many cultures since the transition to farming from hunter-gather lifestyles. (Wikipedia)