Abstract 140

Gomez,-GG; Valdivieso,M

Centro Internacional de Agricultura Tropical (CIAT), Cali, Colombia.

Nutrition-Reports-International. 1988, 37: 6, 1161-1166; 12 ref.

The effects of ensiling cassava whole-root chips (CWRC) for 26 weeks on cyanide (CN) elimination were studied using the contents of 2 silos. Whole-root chips were obtained from 12 month old plants of a medium-cyanide-containing cultivar, CMC-40. Initial total CN contents of fresh CWRC were 503 and 556 mg/kg DM for silos 1 and 2, respectively, and 40 to 43% of total CN was free CN. By the end of the first week of the silage period, most (<90%) of the CN was in the free, more volatile form. By the end of the silage period, total CN concentrations in CWRC silage were 181 and 141 mg/kg DM for silos 1 and 2, respectively, representing 36 and 25% of the initial total CN concentration of the corresponding CWRC; 95% of the total CN was in the free form. Ensiling was an efficient means of reducing the CN content of CWRC. The final DM content in CWRC silage was about 9% higher than that of fresh CWRC. After 26 weeks pH values were 3.82 and 4.13 for silos 1 and 2, respectively, and the average DM content of 3 CWRC silage samples was 41.5 ñ 4.06%. Proximate composition of the oven-dried samples (90% DM on air-dry basis) was crude protein, 2.98 ñ 0.71; ether extract, 1.74 ñ 0.65; crude fibre, 5.14 ñ 1.09; ash, 4.34 ñ 0.35; and nitrogen-free extract, 75.81 ñ 0.71%.