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Bambara groundnut seeds, produced under five levels of irrigation (0-300 mm range) in a suite of controlled-environment glasshouses, were analysed for their proximate composition. There was no significant effect ofwater treatment on the seed composition. Mean values (g kg-I DM) of dry matter, protein, starch, free sugars, non-starch polysaccharides and lipids were 8.91, 2.53, 4.28, 0.15, 2.56 and 0.79, respectively. Bambara groundnut protein was deficient in the sulphur amino acids, methionine and cysteine but met the FA0 requirements for all other essential and non-essential amino acids. Of the non-starch polysaccharides (NSP) of bambara groundnut, the ratio of insoluble to soluble fractions was 57:43.Cellulose accounted for 36% of the total NSP. Approximately 12.8% of the total NSP was resistant to acid and enzymic hydrolysis. This fraction was attributed to lignified seed coat material and low molecular weight phenolic compounds. Tannin complexes capable of precipitating 142.6 g BSA (bovine serum albumin) per kg seed and trypsin inhibitor activity (13 g kg-' DM) were measured in all five bambara groundnut treatments. The presence of these anti-nutrients may have implications for the bio-availability of bambara groundnut protein.

The bioavailability of raw cassava starch from dried, whole roots, as affected by a number of variables, both inherent and processing-induced, was determined in a series of feeding trials using the rat as a test animal. Apparent starch digestibility was in excess of 99% and was unaffected by cassava variety, cyanide content, drying process, fineness of grinding, dietary inclusion level (up to 50% of the diet) and age of the animal. A high level of residual cyanide (406.6 mg kg -dried cassava chips) reduced feed intake and weight gain. Since the floor-drying procedure, whilst effectively reducing the cyanide to an acceptable level, was without effect on the digestibility of cassava starch, it is recommended that this process be adopted for drying high cyanide cultivars of cassava destined for the animal feed market. This will allow cassava to be incorporated in the diet at a higher inclusion level with no undesirable effects on animal performance.

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