Beef production from the dairy herd

Abstract

Calves born to Friesian dams and sired by Friesian (F × F), Hereford (H × F), Simmental (S × F), Angus (A × F), Limousin (L × F), South Devon (SD × F), Blonde d'Aquitaine (BA × F), Red Devon (RD × F), and Charolais (C × F) sires were born and reared on 21, 18, 16, and 19 Waikato dairy farms in the spring seasons of 1973–76 respectively. Weaned calves were transferred to grazing farms at approximately 4 months of age. The “environment” of the dairy farm was an important source of variation in growth rate from birth until transfer. Some of this variation was associated with method of rearing. Over all years live-weight gain from birth to 12 weeks of age was 18.7 kg greater on farms with suckled calves than on those farms using artificial rearing techniques. Compared with the F × F in each year, CxF, L × F, SD × F, S × F, and BA × F calves were heavier and A × F, RD × F, and H × F were lighter at transfer in the descending order given. These differences reflected birth weight to a greater extent than post-natal growth rates. Individual sires-withinbreeds significantly affected age-corrected transfer weight. Heritability estimates were generally higher for age-corrected live weights than for growth rates. Steer calves grew faster than heifers, but age of dam did not affect post-natal growth.