Breeding strategies for genetic improvement of dairy cattle in Zimbabwe. 2. Economic evaluation.
1993
Mpofu N. | Smith C. | Van Vuuren W. | Burnside E.B.
An economic evaluation is made on the public investment in breeding strategies for commercial dairy cattle in Zimbabwe, including import of germplasm. Nine strategies are evaluated for their net present value after 25 yr. Benefits are estimated using realistic predictions of the value of the genetic improvement. Cost estimates for the strategies are from farmer and breed organizations in Zimbabwe. The evaluations are based on constant 1991 Zimbabwean dollars. Results are given for an initial genetic difference in milk yield between the exporting country (US) and Zimbabwean populations of 1.25 standard deviations, a genetic correlation in performance between the countries of 0.7, a discount rate of 10%, and a relative value of the US dollar to the Zimbabwe dollar of 1:3. The sensitivity of results to variation of these parameters is investigated. The economic ranking of the strategies is quite different from their genetic ranking. For the standard set of parameters, some of the strategies are not economically viable (with negative present value), including two that ranked high in genetic improvement. The strategies that rank best economically are the continuous importation of elite embryos and the use of elite foreign semen on elite domestic cows to breed bulls for commercial semen use in Zimbabwe. Strategies involving local progeny testing have smaller benefits. Variation of the parameters affects predicted economic benefits greatly but affects ranking of the strategies less. Continual semen importation strategies rank high economically when the price of imported semen is low.
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