Published online by Cambridge University Press: 02 September 2010
1. Nitrogen balance studies have been conducted on eight early-weaned calves receiving four diets containing, respectively, groundnut meal, groundnut+lysine, groundnut+lysine+methionine and white-fish meal as the major protein source.
2. There were no significant differences between groundnut meal diets i n any of the measurements examined. On the fish meal diet all measures of nitrogen retention tended to be higher than the corresponding values for groundnut meals.
3. Daily live-weight gains were significantly higher on the fish meal diet than on any of the groundnut diets (P<0·05).
4. It is suggested that the supplementary amino acids, being highly soluble, were rapidly deaminated by rumen micro-organisms.