| This paper related closely to the demand of high-quality Merino sheep breeding in Xinjiang Autonomous Region, based on gene flow method, make use of the system analysis to determine high-quality Merino sheep breeding objectives and traits, adopted balance method to calculate the marginal profits. Adopted gene flow method and applied special breeding scheme software ZUPLAN to analysis the breeding effect of current Merino sheep breeding scheme. Then study different factors of current breeding scheme, such as breeding flock proportion, useful life of ram and ewe, mating ewe proportion of progeny test in breeding flock, population size and so on, optimize them and get following conclusions:1. According to our country condition of the superfine Merino sheep breeding, producing and marketing, and consider the future quality trend in a period of time, calculating to establish essential economics , biology and breeding technique parameter, and to establish 3 type and 6 production traits objectives. The marginal profits analysis show that superfine Merino sheep 3 type traits: wool traits, reproduction traits, growth traits weight proportion is 66.43:25.12:8.41, similar to 8:3:1, that means wool traits of superfine Merino sheep have the larger economic value.2. Optimizing analysis show that the breeding scheme does not come to best efficiency in population size, proportion of breeding flock, useful life of ram and ewe, and have good space to improve. The generation interval of current breeding scheme is 4.48 years, ratio of input and output is 1:14.04, the number of ram progeny test is low, and the useful life of ram and ewe is longer and so on can be improved.3. The optimizing research shows that ram and ewe age of breeding flock and use-age has large effect to breeding profit. When ram use one year, ewe use 2 years in breeding flock, and ewe uses 5 years in production flock will acquire ideal breeding efficiency. Useful life of breeding flock ram should not surpass 4 years according to inbreeding increment.4. When proportion of breeding flock size is fixed, the population size enlarge every 5000, breeding profit and genetic gain will roughly increase 7.21% and 6.60% respectively, and breeding cost will decrease 22.97%. But only enlarge population size, it will decrease breeding efficiency and population multiple breeding gain, we should enlarge breeding flock size and active breeding flock proportion in practice.5. After optimizing every effect factors, the current breeding scheme can reach to best benefit of genetic gain and breeding efficiency in following condition: breeding flock proportion is 65%, progeny test mating ewe proportion is 50% in breeding flock and the ram number of progeny test is 15. The population multiple breeding gain,and breeding profit will reach to 18.631 Yuan RMB and 375.569 Yuan RMB respectively, it will increase 36.83% and 153.41% respectively compared with current breeding scheme of 13.616 Yuan RMB and 148.208 Yuan RMB.6. The inbreeding research shows that inbreeding coefficient should not surpass the 0.3% when population is in best situation, useful life of breeding flock ram should not surpass 3 years when remain ram is 10. We also can setup open breeding system and introduce ram or sperm to solve inbreeding problem.7. The paper further analyzes the no progeny test breeding scheme, the finding show that the progeny breeding scheme is superior to no progeny breeding scheme, so we should take the progeny test breeding scheme in the practice.
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