Post-weaning growth, ultrasound and skeletal measurements, muscularity scores and carcass traits and composition of progeny of five beef suckler cow genotypes

Post-weaning growth, ultrasound and skeletal measurements, muscularity scores, and carcass traits and composition of the progeny of spring-calving Limousin (L), Charolais (C), Limousin × Holstein-Friesian (LF), Limousin × (Limousin × Holstein- Friesian) (LLF) and Simmental × (Limousin × Holstein-Friesian) (SLF) cow genotypes was determined over 3 years. Bull and heifer progeny were slaughtered at ~460 and ~610 days of age, respectively. Post-weaning growth did not differ significantly between the genotypes. Progeny from LF and SLF cows had the highest (P<0.001) carcass gain per day of age, whereas progeny from L and C cows had the highest (P < 0.01) carcass conformation score and lowest (P < 0.001) fat score. The proportion of meat in the car- cass was higher (P < 0.001) and bone lower (P < 0.001), and meat to bone ratio higher (P < 0.001) for the progeny of L cows than all other genotypes, which were similar. Carcass fat proportion was similar for progeny of L and C cows and lower (P < 0.001) than LLF and SLF, with LF being intermediate. The progeny from L cows tended to have the greatest proportion of hind-quarter in the carcass. Genotype effects were mini- mal when the proportion of high-value cuts was expressed relative to weight of meat in the carcass and hind-quarter. In conclusion, there was no effect of cow genotype on the performance of their progeny from weaning to slaughter. However, crossbred cows with good maternal (milk) traits produced progeny with a higher carcass weight per day of age, whereas the purebred continental cows produced progeny with superior carcass classification traits.