Belmont Crossbreeding – Phase 1

Summary

Breeds of African, European and Indian origins were used to investigate how productivity of the northern beef industry may be increased through greater use of heterosis and better matching of genotypes to markets, environments and management systems. Productivity incorporates efficiency of growth and reproduction, survival rates, 'easy-care' characteristics, resistance to environmental stresses and meat and carcase qualities. These variables were measured and used to develop models that predict the productivity of different genotypes over a range of breeding, rearing and finishing environments.

Preliminary data indicate that no breed excels in all components of production and that appropriate crossbreds have far higher productivity than any straightbred, without the need for additional inputs. Growth from birth to 18 months and resistance to ticks and worms are the only measurements completed. They show differences between genotypes of over 33% in liveweights at each age and over 100% in resistance to parasites. Crossbred genotypes of high mature size had the highest absolute growth rates but in the presence of parasites, crossbred genotypes of high resistance had higher efficiency of growth. Although objective measurement of meat tenderness favoured the taurine breeds, breed differences were not detected by taste panel tests. Positive identification of the most productive genotypes for each set of conditions will follow completion of measurements of all production variables in 1998.