| Popis: |
The approach of Harris (1970) and Harris et al. (1984) was used to develop mathematical profit functions for describing the bioeconomic objectives in an integrated three-way cross commercial broiler production system. The reproductive and productive performances of the pureline maternal grandparent female and the single cross female parent were included to reflect the impact of the traits expressed in those populations. The resulting complex function was approximated with linear and quadratic equations. Inputs (costs) in the system included feed, housing, labor and facilities, and processing. Outputs (returns) included salvage value of the cull hens and the processed cut-up broilers. A systematic procedure was developed to calculate relative economic values of the traits in the breeding objective from the bioeconomic function. The traits were boiler livability, boiler weight, proportion of carcass, proportion of breast-thigh-leg, broiler feed consumption, grower livability, layer livability, rate of lay, settability, fertility, and hatchability. The relative economic values thus obtained were 1.51, 1.00, 5.99, 3.21, —.20, 0, 0, 0, 0, 0, and 0 in paternal grandparent; 4.48, 1.00, 5.99, 3.21, —.20, 3.00, 3.10, 4.58, 2.97, 3.04 and 3.04 in maternal great-grandparent male; and 9.30, 1.00, 5.99, 3.21, —.20, 7.88, 8.15, 12.06, 7.80, 7.97, and 7.97 in maternal great-grandparent female, for the traits in the above order. |
