Evidence of the Impact of Activated Charcoal on the Availability of Hydrogen Cyanide in Cassava Root Meal Diets of Growing Pigs

Abstract

The impact of activated charcoal on the availability of hydrogen cyanide in cassava root meal diets of growing pigs was examined using Large White x Landrace crosses (n=32, age = 16 weeks, x̅ = 27.32±0.24 kg) assigned to eight groups with four pigs per group, and each pig was a replicate. Two sets of four diets were formulated. Maize was replaced with cassava root meal (CRM) at 0, 25, 50 and 75% in both sets but the first set had no activated charcoal while the next set of four diets had activated charcoal (AC) at 40g/kg as a supplement per diet. The experiment was a 2 x 4 factorial arrangement in a completely randomized design. The result indicated that the interaction effect differs significantly (p< 0.05) for Daily Feed Intake (DFI), and Hydrogen Cyanide (HCN) intake. Diets with Activated Charcoal Supplementation (ACS) were significant (p<0.05) with higher feed intake (1.50 vs 1.61 kg/d) and hydrogen cyanide (15.29 vs 16.60 mg/kg) intake. Crude protein, ether extract, crude fibre, ash, nitrogen-free extract and hydrogen cyanide digestibility showed significant (p<0.05) effects of the interactions. Charcoal supplementation significantly (p<0.05) improved hydrogen cyanide digestibility (57.98 vs 68.17 %) while those of crude protein (62.83 vs 60.88 %) and ether extract (91.52 vs 89.73 %) were significantly (p<0.05) depressed. Grower pigs fed 0, 25, 50 and 75% CRM without activated charcoal supplementation had significant (p<0.05) dissimilarity in cyanide degradability in the stomach, caecum and the small intestine. In the stomach and caecum the values were higher at 75% CRM level whereas in the large intestine, it was at 50% CRM level. Significant (p<0.05) differences existed in the cyanide degradability in all segments with activated charcoal supplementation. It can be concluded that grower pigs could tolerate up to 75% cassava root-based diets as a replacement for maize with or without activated charcoal supplementation. The hydrogen cyanide content of cassava root meal that imposed limitations on the use of the meal in diets of pigs could be overcome by supplementing with activated charcoal for increased degradability in the stomach and caecum.