Relative economic values for Canadian beef production using specialized sire and dam lines

A deterministic herd-level model was developed to simulate profit (income minus expense) from 100 beef cows in western Canada. The cow-herd was composed of three synthetic strains (M1, M2 and M4) mated in rotation and at equilibrium with respect to age and genotype. Two synthetic "terminal sire" strains (M3 and TX) were also simulated. Heifers were mated with M3 to minimize dystocia when calving at 2 yr of age. Cows greater than 5 yr of age were bred to TX. Baseline economic and biological data were obtained from Beefbooster breeders. Endpoints considered were weaned calves, backgrounded steer and heifer calves, finished steers and heifers, and carcass weight and grade. Variable costs included feed consumed by the cow-herd (76% of variable costs to weaning), non-feed items to weaning, and feed consumed by market progeny after weaning. Relative economic values (âi) were changes in profit ensuing from unit changes of the baseline strain specific biological characteristics. Elements of â were economic values...