Effects of Fermentation and Enzyme Treatment on Nutritional Composition, In-vitro Digestibility, and Cyanide Reduction in Cassava (Manihot Esculenta) Root-Leaf Meal

Cassava root-leaf is a readily available energy and vitamin source for use in animal feed, but their high cyanide, crude fiber,  low crude protein content, and low digestibility limit their use as pig diets. Therefore, there is a need to reduce the cyanide content and improve the nutrient content of the root-leaf meal to have it as an alternative to maize meal in pig diets. This study evaluated the effect of Aspergillus niger, spontaneous fermentation, Natuzyme® Enzyme, and Lactobacillus brevis treatment on the nutritional composition, In-vitro dry matter digestibility (IVDMD), and cyanide reduction in cassava root leaf meal for use in pig diets. A 4×4 Factorial Completely Randomized experimental design was used to evaluate the nutritive contents of KME 01 cassava variety. Samples of Cassava root-leaf meal (CRLM) were allocated to five treatments  (T1–T5) in three replicates. The treatments included untreated cassava root-leaf meal (T1); Cassava root-leaf meal fermented by Aspergillus niger (T2). Cassava root-leaf meal fermented naturally (T3); Cassava root-leaf meal treated with enzyme (Natuzyme ®) (T4); Cassava root-leaf meal fermented with Lactobacillus brevis (T5). The samples were fermented at 37°C for a total of 96 hours. After every 24 hours, samples were collected and analyzed for proximate composition, hydrocyanic acid (HCN) content,   and IVDMD. The results showed that Spontaneous fermentation significantly improved cassava root-leaf meal's digestibility and nutritional value from 15.02% to 55.56%. Spontaneous fermentation decreased HCN from  45.00 ppm to 8.00 ppm and crude fibre (CF) from 5.16% to 3.87 %, and increased dry matter (DM) from 93.67% to 98.62%, ether extract (EE) from 0.91% to 1.18 %, and crude protein (CP) from 7.47 % to 11.09 %. These improvements suggested that fermented cassava root-leaf meal is a viable substitute for maize in pig diets. The results indicated that spontaneous fermentation is an effective method to improve digestibility and reduce hydrogen cyanide content. Therefore, the study provided evidence for the inclusion of FCRLM in pig feed as a locally available alternative to maize, promoting sustainable feeding strategies for livestock production. The study recommended that future studies should be conducted to evaluate the effects of fermented cassava root-leaf meal-based diet on pig performance and carcass quality characteristics.