试论牛品种经济类型的形成与划分问题

A Discussion on Formation and Differentiation of the Economic Types among Cattle Breeds

传统方法将世界上成百上千的牛品种划分为乳用、肉用、兼用和役用牛四大经济类型。本文分析证明:以肉用性能中的肉块产量(率,Cutability)或肉质指标作为牛经济类型划分缺乏根据;试提出以产奶指数(Milk production index.MPI)作为量值指标。经对国内外173个牛品种MPI值计算,提出乳用的MPI>7.9.肉用牛(包括役用牛)的MPI<2.4.而兼用牛为2.5≤MPI≤7.9。与传统方法相比,以MPI划分结果与前者吻合程度84.4％以上,且更简明,也避免了传统方法的不确定性。

Hundreds of cattle breeds in the world can be divided into four economic types in-cluding dairy. beef.dual--purpose and draft by force of long tradition and utility. It is argued in this paper that it were insufficient grounds to distinguish these different types by means of marbling, tenderness and cutability of economic traits of carcass. the MILK PRODUCTION INDEX(MPI,a number of milk production kg, per kg live weight, peryear/lactation of per adult cow) was put forward and the MPI of 173 cattle breeds in theworld was caculated. The result showed that MPI of dairy type breeds>7. 9; that ofbeef type breeds>2. 4; that of dual-purpose breeds is between 2. 4 and 7. 9; that ofdraft type breeds seems alike that of beef type breeds.