Comparison of ‘Grasslands Ariki’ and ‘Grasslands Ruanui’ ryegrasses for lamb fattening at different stocking rates in Southland

Abstract

Experiments in spring and autumn of 2 years are reported in which the growth of lambs was compared at various stocking rates on either 'Grasslands Ariki' or 'Grasslands Ruanui' ryegrass growing in association with 'Grasslands Huia' white clover.In spring no differences in lamb meat yield or ewe body weight were associated with ryegrass variety, but in autumn heaviest carcass weights were produced from lambs on Ariki pastures.Stocking rate was more important in determining animal productivity than was grass variety. Highest carcass weight/ha and live-weight change was achieved at the highest rates of stocking, except in autumn of the first year.In autumn of the second year, lambs at the highest rate on Ariki pastures made greater total live-weight gain than those at the same rate on Ruanui. The significance of this to the agriculture of the region is mentioned.