Growth, carcass, and meat quality of beef-sired Holstein crossbred heifers under intensive production

Beef-on-Dairy systems increasingly use beef sires on Holstein dams, yet evidence on the female progeny remains scarce. This study characterised 72 Holstein × beef crossbred heifers sired by Belgian Blue (BB), Piemontese (PIE), Limousin (LIM), or Simmental (SIM) bulls under a uniform intensive-finishing system and slaughtered at 465 ± 18 days. To test sex and sex × sire-breed effects, the dataset was extended by combining the heifers with male crossbreds from the same population. Sire breeds differed mainly along a yield–muscularity axis: SIM achieved the heaviest carcases (294.9 kg) and the highest intramuscular fat (3.84%); PIE produced the leanest, most muscular carcases (66.0% muscle, 22.63% protein); BB showed the most saturated lipid profile; and LIM was intermediate. Individual-level PCA combined with MANOVA confirmed the multivariate sire-breed effect (Wilks’ Λ p < 0.001). The joint factorial analysis of both sexes revealed three significant sex × sire-breed interactions, all lipid-related: the atherogenic (p < 0.05) and thrombogenic (p < 0.05) indices and the SFA/UFA ratio (p < 0.01). These results indicate that sire-breed selection in Beef-on-Dairy programmes is not sex-neutral and should be tailored to the intended sex of the progeny, particularly as sexed beef semen enables differential targeting of male and female crossbred markets. As these findings are based on four sires per breed and a single production system, they should be confirmed in larger multi-system studies with more sires per breed. Sire breed differentiated growth, carcase, and meat quality of Holstein × beef heifers. A joint factorial analysis revealed significant sex × sire-breed interactions for the lipid health indices (atherogenic and thrombogenic index) and the SFA/UFA ratio. Optimal sire-breed selection in Beef-on-Dairy programmes is not sex-neutral and should be tailored to the intended sex of the progeny.