Growth rates of lambs and adult sheep grazing forage sorghums and lucerne

Abstract

Daily growth rates of adult sheep grazing a sorghum-sudan grass hybrid, Sorghum almum and lucerne were 87 g, 73 g and 171 g a head. Weaned lambs had low daily growth rates on the forage sorghums, 84 g and 48 g a head, compared to 159 g a head on lucerne. On lucerne growth rates of lactating ewes and their lambs were also higher than those on forage sorghums. In vitro dry matter digestibilities of the forage sorghums were ' low, ranging from 52 to 61 per cent, and were considered to be an important factor contributing to the low growth rates of weaned lambs.