EVALUATION OF STRATEGIES FOR CROSSBREEDING OF DAIRY-CATTLE IN BRAZIL

To compare breeding strategies, economic performance was calculated for 376 cows of six red and white Holstein-Friesian x Guzera crossbred groups (1/4 to ≥31/32 European grades), based on their accumulated dairy production (914 lactations on 60 farms) and on culling or death observations of 87 nonfreshening heifers. Performance was predicted from a genetic model based on additive-dominance and inter se mating effects for the following: utilization of F1 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 farms, 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 farms 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. Important economic gains may accrue from choice of a breeding strategy to match the appropriate animal genetic resources to husbandry practices. Continuous F1 heifer replacement programs may have sound economic basis, particularly for low management level farms. Crisscrossing was the second best alternative for those farms. On the better-managed farms, modified crisscrossing and upgrading had similar performance under present prices, but the former would be more profitable under higher pricing of fat and protein. © 1990, American Dairy Science Association. All rights reserved.