Abstract

There are variations in stature between beef and dairy breeds (and their crosses) which are an indirect result of genetic selection and farm management for different production objectives. The aim of this experiment was to examine the effect of breed on bone morphology in the distal epiphysis of the metacarpus. The metacarpus was collected from 9.5-year-old Angus (AA), Angus-Friesian crossbred (AF), Angus-Jersey crossbred (AJ) and Angus- (Friesian cross Jersey) crossbred (AK) cows. Bone morphology in the epiphysis was assessed using peripheral quantitative computed tomography (pQCT) for the medial and lateral condyles of the epiphysis 7 mm from the distal metacarpus. The greater total bone cross-sectional area of AA and AF could be associated with minimising strain on the articulating surface of the metacarpus due to greater joint surface area. Therefore, the greater total bone cross-sectional area may be an indirect result of a greater level of muscularity in beef breeds with a heavier mature weight.

MJ, Gibson, RE Hickson, KE Dittmer, PJ Back, NM Schreurs, and CW Rogers

New Zealand Journal of Animal Science and Production, Volume 82, Online, 82-87, 2022