Journal of Dairy Science · 1990 · 89 citations · 9 references
AgricultureAnimal SciencesDairy ScienceDairy Herd ManagementLivestock ProductionBreedingCrossbreeding SystemsDairy ProductionGenetic Improvement Of LivestockMilk ProductionCrossbreeding EfficiencyCrossbreeding ParametersCrossbreeding Schemes
To compare breeding strategies, ec0nomic perfonnance was calculated for 376 cows of six red and white Holstein-Friesian x Guzera crossbred groups (1/4 to ~1/32 European grades), based on their accwnulated dairy production (914 lactations on 60 fanns) and on culling or death observations of 87 nonfreshening heifers. Perfonnance was predicted from a genetic model based on additive-dominance and inter se mating effects for the following: utilization of Fl females, upgrading to Holstein-Friesian, new synthetic breed, crisscrossing, and modified crisscrossing (of Holstein-Friesian sires for two generations and zebu sires for one generation). On the better-managed fanns, profit per day of herd life for those strategies, was equivalent to, respectively, 1.82, 1.36, -.33, .75, and 1.36 kg of milk, whereas corresponding equivalence on low management level fanns was 4.64, -.95, 1.37,2.72, and 2.23 kg. Differences between groups in culling and mortality rates were considerable in the low management level, influencing herd life and heifer cost and reducing profit of high European grades. hnportant economic gains may accme from choice of ~bree<!ing strategy to match the appropnate ammal genetic resources to husbandry practices. Continuous PI heifer replacement programs may have sound economic basis, particularly for low management level fanns. Crisscrossing was the second
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Dairy Production and Reproduction in Holstein-Friesian and Guzera Crosses
F. E. Madalena, Abílio Lemos, R. L. Teodoro et al. · Journal of Dairy Science · 1990 · 78 citations · Full text