Effects of pasture allowance in winter on liveweight, wool growth, and wool characteristics of Romney ewes

Abstract

Abstract In each of two years, pasture allowances of 0.7, 1.2, 1.7, or 2.2 kg dry matter (DM)/ewe per day were offered to groups of Romney ewes for 6 weeks in June — July. The ewes were then run together until weaning in December. In Year 1 there were 70 2-year-old ewes per group; mean initial liveweight was 47 (SE 0.25) kg. In Year 2 each group comprised 25 2-year-old ewes with a mean initial liveweight of 48 (SE 0.49) kg and 25 6-year-old ewes with a mean initial liveweight of 57 kg. For liveweight change (g/day), the inverse linear relationship with pasture allowance (kg DM/ewe per day) for ewes with one lamb in utero was: [liveweight change = 136 (SE 4.4) — (132 (SE 5.0) allowance)]. On average, the pasture allowance that resulted in zero liveweight change was predicted to be 1.0 kg DM/ewe per day. With a pregrazing pasture mass of c. 2000 kg DM/ha, zero liveweight change was associated with a residual pasture mass of 760 kg DM/ha, a utilisation of 66%, and an apparent intake of 0.59 kg DM/ewe per day...