在不同杂交方案下猪的完整繁育体系的经济效益比较分析

木文用系统动力学专用仿真语言──Ｍｉｃｒｏ—ＤＹＮＡＭＯ分别模似了♂约克夏（Ｙ）×♀长白猪（Ｌ）的二元杂交、♂Ｙ×Ｆ１♀（ＹＬ）的回交、♂杜洛克（Ｄ）×Ｆ１（ＹＬ）的三元杂交完整繁育体系及无育种群的三元杂交非完整繁育体系。在ＩＢＭ－ＰＣ／ＸＴ电子计算机上实现仿真运算，得出：（１）由育种群、繁殖群和商品生产群构成的宝塔式繁育体系结构，按各群体母猪数所占比例，二元杂交分别为２．３６％、１０．７５％和８６．８９％，回交分别为２．３８％、１０．７５％和８６．８７％，三元杂交分别为２．７３％、１０．７１％和８６．５６％。为建立适合我国国情的具有合理猪群结构的完整繁育体系提供了科学依据。（２）全面分析了繁育体系的投入与产出，按投入产出比、每头种母猪的利润和单位商品肉猪（活重９０ｋｇ）利润三种指标比较了三元杂交、回交、二元杂交完整繁育体系和非完整繁育体系下三元杂交的经济效益，均得出同样结论，以单位商品肉猪１１年内获得的累积利润计算，完整繁育体系与非完整繁育体系比较，三元杂交多盈利２１．９３元，回交多盈利１７．９９元，二元杂交多盈利４．６４元，说明建立完整繁育体系具有长远的经济意义。从我国现实情况出发，以建立三元杂交的完整

Comparative analysis of the economic benefits of the integrated pig breeding system in different cross schemes

In the present paper,the integrated breeding systems of the single cross between male Yorkshire (Y) and female Landrace (L),the back cross between male Y and female F1 (YL) and the three -breed cross between male Duroc(D) and female F1 (YL) were simulated separately by using the specific simulating language of the systematic dynamics,Micro-DYNAMO,with the tbree - breed cross in the non-integrated breeding system which has no nucleus herd as control. The simulating calculation was realized on IBM -PC/XT, The main conclusions drawn are as follows: (1)In the pyramidical breeding structure made up of the nucleus herd. the multiplication herd and the commercial herd,the proportions of the three sow hreds to the total number of sows were 2. 36%, 10. 75 % and 86. 89%, respectively; in the single cross scheme, 2. 38%, 10. 75%and 86. 87%, respectively, in the back cross scheme; 2. 73%, 10. 71 %and 86. 56%,in the three-breed cross. This should provide a theoritical basis for setting up the integrated breeding system with reasonable pig herd structure suitable for China. (2)setting up an integrated breeding system will provide long-term benefits. Under the integrated system,the profit of three -breed cross was the highest and that of the single cross was the lowest. Therefore,China should prefer the three breed cross or back cross to single cross in the integrated breeding system in the future. (3)An integrated breeding system should be based on large-scale production.