Yangyangfa 養羊法

Yangyangfa 養羊法 "Methods of sheep breeding", also called Bu Shi yangyang fa 卜式養羊法 "Bu Shi's methods of raising sheep", is an agricultural book attributed to Bu Shi 卜式, an entrepreneur of the Former Han period 前漢 (206 BCE-8 CE) who regularly submitted cattle and sheep to the imperial army. He was, therefore, granted the title of court gentleman (lang 郎) and later even rose to the office of Censor-in-chief (yushi dafu 御史大夫).

The imperial bibliography Jingji zhi 經籍志 in the official dynastic history Suishu 隋書 says that the book was still listed in Liang-period 梁 (502-557) catalogues but was already lost during the early Tang period 唐 (618-907).

It is rather improbable that Bu Shi was the author of the book because it is known that he was illiterate. The text is possibly quoted (without indication of a source) in a chapter on the raising of sheep in Jia Sixie's 賈思勰 (fl. 544) agricultural treatise Qimin yaoshu 齊民要術 from the Northern Wei period 北魏 (386-534). These fragments were collected during the Qing period 清 (1644-1911) by Ma Guohan 馬國翰 (1794-1857) and are to be found in his series Yuhanshanfang jiyi shu 玉函山房輯佚書.