Closed loop agriculture-for the 21st century

摘要

Animal husbandry - the practice of breeding, caring for and slaughter of animals - has been part of modern farming in many cultures since we made the transition from beina hunter-aatherers.The relationship between farmers and their animals is millennia-old - with pigs first kept 7,000 BC in the Middle East and China, and cattle have been domesticated for around 10,500 years.