The use of double-muscled cattle breeds in terminal crosses: Animal performance and blood metabolites
Eighty-nine calves born of dams from British (50% Hereford and 50% Red Angus) and Continental (50% Simmental and 50% Maine Anjou) breeds crossed with Charolais (CH), Belgian Blue (BB) and Piedmontese (PM) sires were used to evaluate the productivity of using double-muscled cattle in terminal crosses. Breed of sire did not exert a significant effect on any parameter measured before weaning. Calving difficulty was related to breed of dam, being higher in British than in Continental dams (P < 0.05) and tended to be higher for male than for female calves (P < 0.10). Average daily gains to weaning and weight corrected at 200 d were higher for male than for female calves (P < 0.05), and for calves from Continental dams than for those from British dams (P < 0.05). Average daily gain during backgrounding was higher for CH than for PM-sired calves (P < 0.05). Also, ADG in feedlot (backgrounding + fattening ) was higher for male than for female calves (P < 0.05). Slaughter weight and dressing percentage were higher in calves from Continental dams than in those from British dams (P < 0.05). At similar backfat thickness, slaughter weight was higher in male than in female calves (P < 0.05). Total plasma cholesterol, HDL cholesterol and triglycerides were higher in PM sired cattle than in those sired by CH (P < 0.01 to 0.10). Similarly, cattle from British dams presented higher values of plasma cholesterol, HDL cholesterol and LDL cholesterol than cattle from Continental dams (P < 0.01 to 0.05). Insulin and IGF-I values increased with age (P < 0.01). Plasma insulin concentrations during fattening were higher for PM than for BB or CH sired cattle (P < 0.05), for cattle from Continental than from British dams (P < 0.01) and for males than for females (P < 0.01). During fattening, IGF-I values were higher in male than in female cattle (P < 0.01). The use of double-muscled sires in terminal crosses resulted in little effect on performance of the progeny.
J. R. Seoane1, H. Lapierre2, and G. L. Roy2
1Département des sciences animales, FSAA, Université Laval, Québec, Canada G1K 7P4 (e-mail:
firstname.lastname@example.org); 2Agriculture and Agri-Food Canada, Dairy and Swine Research and
Development Centre, Lennoxville, Quebec, Canada J1M 1Z3. Contribution no. 6172, received 5 November 1998,
accepted 13 July 1999.