Abstract

Reproductive technologies may be defined as any technology which impacts on the reproductive potential of the herd. Reproductive technologies applicable to beef breeding cows can broadly be classified into those requiring either a low, medium or high technical input. The examples of 'Low Technology' options discussed are: age at first joining, breed/cross or strain of cow, time of calving, and pregnancy diagnosis. In traditional breeding cow herds, cow productivity can be increased by modest amounts (5-10%) if only single-option 'low tech' changes are implemented. However, these fundamental technologies need to be well developed before higher technologies can be successfully applied. Two examples of 'Medium Technology' strategies that have been available for some time include oestrous synchronisation and multiple suckling. Oestrous synchronisation has the potential to facilitate an increase in the number of herds adopting yearling heifer mating. Twin suckling through fostering an additional calf has been demonstrated to significantly increase the number of calves weaned per cow. Emerging 'High Technology' options include: twinning, controlling the sex of calves at conception and cloning. Future developments in embryo technologies are vital in many of the emerging reproductive technologies for beef cows.

WH, McMillan

Proceedings of the New Zealand Society of Animal Production, Volume 54, , 345-350, 1994