With the commercialization of agriculture during the industrial revolution, all kinds of new varieties were developed that grew faster, ate less and produced more offspring than their forebears.
十八世紀中葉產業革命後，畜禽商品化，專業養殖開始取代農家飼養，各種檢定制度提供育種學家豐富資料，長得快、吃得少、生得多的各式合成品種不斷上市。