| It is anticipated that the inclusion of high quality and high yield in the breeding objective has some consequences on the design of progeny testing scheme in Longzhou cow. The breeding objective traits of Longzhou cow were studied and determined by system analysis method. The marginal profit for each objective trait was estimated using the balance method and the relative computing formula for the objective traits were presented. A complex deterministic approach (ZPLAN), which is based on the gene flow theory and systematic analysis theory, was used to optimize the opened nucleus breeding programs for NMCG. Annual monetary genetic gain and breeding profit were used to evaluate alternative breeding strategies. On the base of analyzing the anticipated breeding effects of current breeding scheme, the following factors which affect annual monetary genetic gain and breeding profit are considered: structure of different population, dimensions of different population, the fixed number of using years of seedstock. The strategies to improve current breeding scheme and optimized breeding plan were proposed.1. The research analyzes the growth capability, reproduction capability, expenses of feed and management, energy need, energy-containing of feed and so on. Combining condition of Longzhou cow production, breeding, market and further developing trend, to calculated the marginal profit of the three kind traits-growth, carcass quality and reproduction by balance method and confirmed the breeding goal traits. These characters'economic weight including traits-growth, reproduction and carcass quality were measured. The ratio of relevant economic importance of the three kinds of traits-growth, milk traits and secondary traits is 54.22%:21.88%:23.9%,and approximates 2:1:1. The ratios of relevant economic importance of the seven objectives,include daily gain, milk fat ratio, breeding time ,growth capability, carcass quality, utilization lifespan, incidence of mastitis were 47.99%, 21.88%,20.76%, 4.14%, 2.09%, 1.78%and 1.36% respectively ;and the Marginal profit is $22.2769, $31.25,$38.544,$-2.1977,$194.502,$0.1798,$-4.2188. So daily gain occupies larger economic weight, and better than milk fat ratio and breeding time. It is important to select growth traits in the selection process of Longzhou cow as beef cattle. 2. In the condition that planning period is 20 years and the size of population is 100 million, optimum analysis result proved that the return for the current breeding scheme is $26.8036, breeding output is $139.6700,breeding input is $18.4800 ,the breeding profit is $121.1900, the mean generation internal of the population is 5.4706 years, and the ratio of input and return are 1:7.56. Compared with domestic and foreign research kept some room to be improved. The genetic gain of every selecting trait for every selecting period respectively is that daily gain increases 2.86g, milk fat ratio increases 1.00 kg; breeding time shortens 0.61d, growth capicity improves 1.26kg; carcass quality and marbling improve 1.01 commercial grade, utilization lifespan shorten 2.81d, incidence of mastitis decrease 0.08% respectively.3. With the increase in the proportion of breeding groups, synthetical breeding development, breeding output and breeding profit all will increased, however breeding input will decrease.4. Synthetical breeding development, breeding output and breeding profit and breeding return and breeding profit will increase as the annual ratio of seed bull increased in breed herd.5. Synthetical breeding development, breeding output and breeding profit will increase as the ratio of tested bull increased in breed herd, but breeding profit will increase in the first instance, and then will increase.6. Breeding output, breeding profit and breeding profit will increase as the proportion of seed cow increased in breed herd. Annual monetary genetic gain will increase and come to a head and then will decrease slowly. The proportion of seed cow in breed herd is 10.0%, and then annual monetary genetic gain will decrease.7.With the expanded of population and decreased of breeding input ,however the Synthetical breeding development, breeding output and breeding profit will be increase.8. It is concluded that the optimal breeding scheme for the utilization lifespan for different selecting groups by analysis, the lifespan of seed bull and general bull were utilized 2 year, seed cow and general cow were utilized 5-6 year, tested bull was utilized 2-3 year, tested cow was 5-6 year, commercial bull was utilized 3 year, and commercial cow was utilized 7 year.9. Through comprehensive analysis in the study, breeding efficiency of the current breeding scheme and breeding efficiency of the utilization lifespan optimized were optimized by contrast analysis, the result is ,optimize all affect factors,population can reach optimal generation alternation is 4.0613 years,increased 25.76% than mean generation alternation 5.4706 year; Synthetical breeding development can reach $ 35.9811,the optimized synthetical breeding development is 34.24% higher than current scheme 26.8036 year;Breeding output can reach $213.9240,which is 53.16% higher than current scheme $139.6700;Breeding profit can be $192.9605,which is 59.22% higher than current scheme 121.1900;Optimized breeding input an output ratio is 1:9.26,which is higher than current scheme 1:7.56.
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