In southern Australia, pastures comprised of annual ryegrass may not meet the nutritional requirements of fast-growing (>250 g/day) lambs in summer–autumn (December–May). An animal house experiment was conducted from March to July 2010 to investigate the use of flaxseed and algae as two potential supplements to improve feed intake, liveweight gain and carcass traits in lambs. One hundred and twenty lambs (in two groups of 60) were fed one of four diets, pelleted annual pasture hay (subterranean clover and annual ryegrass) (T1); pelleted annual pasture hay + flaxseed flakes (T2); pelleted annual pasture hay + algae supplement (T3); pelleted annual pasture hay + flaxseed flakes + algae supplement (T4). All diets were provided on an ad libitum basis with individual feed intake measured daily and liveweight recorded weekly. Lambs offered the flaxseed flakes (T2) treatment grew faster (P < 0.05), had heavier (P < 0.05) carcass weights and greater (P < 0.05) GR fat depth (total tissue depth at 11th/12th rib, 110 mm away from midline) than lambs offered the T1 diet. Lambs offered algae supplement (T3) had lower dry matter intake but growth rate and carcass weight were not affected compared with lambs offered the T1 diet. Lambs offered both flaxseed flakes and algae supplement (T4) had greater (P < 0.05) GR fat than lambs offered the T1 diet. This experiment provides evidence that supplementing growing lambs with flaxseed flakes can increase dry matter intake, growth rate and GR fat depth. In contrast, supplementing with an algae supplement reduced dry matter intake but growth rate and carcass weight were similar to the control treatment.

Lucerne (alfalfa; Medicago sativa L.) is the key forage for grazing in dryland temperate regions around the world. While rotational grazing of lucerne is recommended, in southern Australia the intervals between grazing events are often chosen in an opportunistic manner, to meet livestock production targets and utilise excessive spring and summer growth. To assess whether the persistence of lucerne is sensitive to variations in rotational grazing management practice, we report on an experiment with four sheep grazing treatments that was conducted for 2.5 years, including three summers, in southern New South Wales. The grazing management treatments were a crash-grazing control, frequent grazing, feed-based rotational grazing and time-based rotational grazing, replicated four times. The number of grazing events, percentage of time under grazing, lucerne top dry matter (DM) at the beginning and end of grazing periods and plant density were measured. The results relating to number of grazing events, percentage of time grazing and DM removed during grazing indicated that four grazing practices had been achieved. The treatments all had significant periods of rest for at least 73% of time and were empirically different in their approach but resulted in similar grazing pressures, in terms of overall pasture removed during grazing. Nevertheless, there was little difference in lucerne densities between grazing treatments over the life of the experiment. We conclude that there is flexibility in the rotational management of grazed lucerne provided adequate rest periods are part of the management program.