IMPROVED GRASS CULTIVARS INCREASE MILK AND MEAT PRODUCTION - A REVIEW

Plant breeding and the merit-testing of grass cultivars in multi-site small-plot studies should be supported with some animal production trials if plant improvement is to maintain credibility and remain focussed on feasible, commercially relevant goals. Lactating animals are the most sensitive test animals. Animal production results from cultivar comparisons are considerably influenced by the system(s) of management used. Between-cultivar differences are rarely detected unless pasture is utilised to a high degree. The economic benefits flow mainly from a reduced need for supplementary feed, or in increased carrying capacity. A range of rates of stocking, or a variable stocking policy dependent on minimal sward height or some other objective basis needs to be employed. Where animal production trials have been conducted, they have mainly focussed on cultivars emanating from those plant improvement programmes aimed at improving nutritive value. Given this limitation the reports reviewed provide evidence that grass improvement programmes have raised the feeding value of pasture considerably.