The influence of dietary supplements of DL-methionine on the growth rate of wool

Dietary supplements of DL-methionine (0, 1.9, 3.8, 7.7 and 15.4 g per day) were given to five groups of 15-month-old Merino sheep (five per group) over an 8-week period. The roughage ration given (c. 840 g dry matter per day) comprised oaten chaff (78%), lucerne chaff (20%) and minerals (2%). Significant wool growth responses were obtained (18% above controls) when 3.8 g supplemental methionine per day was given. Changes in the rate of wool growth were paralleled by changes in nitrogen retention. Nitrogen retention was significantly increased above controls when 3.8 g supplemental methionine per day was given. Supplemental methionine did not affect liveweight gains.