Theme 22: Grazing Management
Description
An experiment was conducted at INIA-Tacuarembó Research Station (Uruguay) during 15 June to 4 October 1998, using a Avena Sativa (oat) and Lolium multiflorum (ryegrass) sward to examine the effect of stocking rate (SR; 25 and 35 lambs/ha) and grazing system (GS; strip and 7 days rotational grazing) on sward and lamb performance. SR had a significant effect on lamb performance, being higher the liveweight gain (LWG; 120 vs 98 g/a/d, P < 0.01), hot carcass weight (HCW; 17.7 vs 16.1 kg/a, P < 0.05) and carcass fat cover (GR; 12 vs 8 mm, P < 0.01) of those lambs managed at the lower SR. At the high SR, lambs increased grazing time (405 vs 376 min., P < 0.05). SG did not affect lamb performance, but strip GS reduces lamb grazing time (367 vs 414 min., P < 0.01) and biting rates (22 vs 24 bites/lamb/min., P < 0.01). Post grazing sward height (SH) was highly associated with LWG (LW = - 101,7 + 32.7 SH – 1.49 SH2, R2 = 0.66). This experiment demonstrated that: (a) the productive potential of ryegrass and oat swards to produce high quality lamb meat, (b) the relative low impact of using strip GS to increase lamb performance and (c) the potential use of post grazing SH as a practical tool to predict lamb LWG in this type of swards.
Included in
Influence of Stocking Rate and Grazing System on Lamb Performance of Mixed Oat and Ryegrass Swards in Uruguay
An experiment was conducted at INIA-Tacuarembó Research Station (Uruguay) during 15 June to 4 October 1998, using a Avena Sativa (oat) and Lolium multiflorum (ryegrass) sward to examine the effect of stocking rate (SR; 25 and 35 lambs/ha) and grazing system (GS; strip and 7 days rotational grazing) on sward and lamb performance. SR had a significant effect on lamb performance, being higher the liveweight gain (LWG; 120 vs 98 g/a/d, P < 0.01), hot carcass weight (HCW; 17.7 vs 16.1 kg/a, P < 0.05) and carcass fat cover (GR; 12 vs 8 mm, P < 0.01) of those lambs managed at the lower SR. At the high SR, lambs increased grazing time (405 vs 376 min., P < 0.05). SG did not affect lamb performance, but strip GS reduces lamb grazing time (367 vs 414 min., P < 0.01) and biting rates (22 vs 24 bites/lamb/min., P < 0.01). Post grazing sward height (SH) was highly associated with LWG (LW = - 101,7 + 32.7 SH – 1.49 SH2, R2 = 0.66). This experiment demonstrated that: (a) the productive potential of ryegrass and oat swards to produce high quality lamb meat, (b) the relative low impact of using strip GS to increase lamb performance and (c) the potential use of post grazing SH as a practical tool to predict lamb LWG in this type of swards.
