Comparative economic returns from artificial insemination and natural service in straightbred and crossbred Holstein herds in Venezuela
1991
Holmann, F.J. | Blake, R.W. | Milligan, R.A. | Oltenacu, P.A. | Barker, R. | Hahn, M.V.
Net present values of milk income over feed and breeding costs of AI products (imported semen from 47 US Holstein sires, four imported US bulls for local semen processing, and seven crossbred sires) and natural service bulls (offering either zero or positive genetic gain in milk) under Venezuelan economic and herd management conditions in 1987 to 1988 were determined. Data were from surveys of 157 farms to obtain herd characteristics, input use and costs, and milk prices. A Holstein herd in the highlands and a crossbred Holstein herd in the lowlands were the farm cases. For the Holstein herd, using any of the AI or natural service products resulted in positive economic returns only in herd situations of high daughter milk response to sire selection. For the crossbred farm to maintain the proportion of Holstein genes at 50%, the most profitable alterative was to use natural service bulls offering genetic gain in milk. The most economical choice to upgrade the crossbred farm to 75% Holstein was to invest in locally processed semen from imported bulls. The most profitable use of US Holstein germplasm was to import bulls for local semen processing and to use this germplasm judiciously on selected local dams to produce bulls for use in natural service mating systems.
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