商周青銅器上的側身牛紋有單首單身式和單首雙身式兩大類型。這種紋飾起源于殷商時期商朝統治區,是商文化的產物之一,西周初年向西傳入陜西關中并以此為中心向南傳入長江中上游的漢中盆地、四川盆地、漢東地區。彭縣、漢中、隨州、喀左出土的幾件側身牛紋罍皆來自同一產地——"關中青銅器鑄造中心"。側身牛紋傳播特點的根源是商周之際政治格局變化所引起的中原地區青銅文化中心的西移以及周初分封移民和"班賜宗彝"。

Iconographically, the motifs of cattle profile on Shang-Zhou bronzes can be divided into two categories: the type of one head with one body, and the other type of one head with two bodies. Originated from the area controlled by Shang Dynasty, these motifs were then introduced into the Guanzhong Region in Shaanxi, and began to spread south to the upper and middle basins of the Yangtze River, including the Hanzhong Basin, Sichuan Basin, and Handong Region. Thus, the author suggests that several lei jars with cattle profile that were excavated from Pengxian, Hanzhong, Suizhou, and Kazuo were all produced in the Guanzhong Region. The underlying mechanism is that, after the end of the Shang Dynasty, the bronze culture center moved toward west with the shift of the political and economical center; the spread of cattle profile represented this significant shift. Thus, this article argues that the replacement of Shang Dynasty by Zhou Dynasty and Zhou’s bestowal activities should be viewed as the major underlying mechanism for the spread of cattle profiles.