| It is expected that the inclusion of high quality and high yield in the breeding objective has some consequences on the design of progeny testing scheme in Nei Mongol Cashmere Goat (NMCG). The study was carried out on the utilization of the field data in Inner Mongolia White Cashmere Goat Breeding Form from 1997-2003. The breeding objective traits of NMCG were studied and determined by system analysis method based on the population parameters, biology coefficients and economic parameters. The marginal profit for each objective trait was estimated using the balance method and the relative computing formula for the objective traits were presented also. 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 discounted profit were used to evaluate alternative breeding strategies. On the base of analyzing the expected breeding effects of current breeding scheme, the following factors which affect annual monetary genetic gain and discounted profit are considered: size of population, structure of breeding system, pattern of use of seedstock, and risk of inbreeding. The strategies to improve current breeding scheme and optimized breeding plan were proposed.Marginal profits were analyzed on the present situation of NMCG breeding and the condition of cashmere trade both in domestic and international market. With regard of the analysis result, the breeding objective traits of NMCG included three basic functions: female production (pure cashmere weight, cashmere fibre diameter and cashmere fibre length ), reproduction (number of kids weaned), and growth of the young (live weight for weaned kid, yearling goat and doe). The relative economic value (calculated as sum of weights of individual traits scale to genetic standard deviations) of the three category traits were 78.7%, 11.7% and 9.6% respectively. The economic weighting showed more prominent cashmere purpose feature and higher economic value for NMCG.Optimum analysis result proved that the mean generation interval of the population is 4.57 years and the ratio of input and return for the programme is 1:3.96. It could be concluded that the current breeding scheme did not meet the optimum breeding efficiency and kept some room to be improved. The current breeding scheme was not in the optimum state in the aspects of size of population, proportion of nucleus vs. reproduction vs. production herd, utilization of bucks, and level of opening. To find the optimum breeding scheme, optimum analysis considered that better annual monetary genetic gain and discounted profit could be reached as the proportion of nucleus vs. reproduction vs. production herd were varied 7-9 vs.11-13 vs. 80 percent, the proportion of nucleus does imported from reproduction flock should be less than 20 percent. Breeding effects was influenced by breeding age and lifespan of both bucks and does in the breeding herd to great extent. The change of them would cause the change of selecting method, selection index and population generation interval so as to change breeding profit and genetic gain per year. The study proved that ideal breeding effects could be obtained if lifespan of tested old bucks in nucleus herd was 1 year and other bucks were utilized 3-4 years, that of does was 5 years, the proportion of semen supplied from nucleus bucks for does in production herd was varied from 20 to 40 percentage.Criteria for evaluation of different schemes are annual monetary genetic gain and discounted profit accounting for variation of costs under different schemes. Under the circumstances of the proportion of breeding population was set to a limit, the larger population size was, and the faster breeding development of population was. At the same time, better economic profit could obtained because the regular breeding cost decreased for less breeding cost of each goat with the population size enlargement. For many breeders, staying in business is as i...
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