Assessment of fermented and unfermented cassava peels as a substitute for animal feed

Agro-waste products, such as cassava peels, which are usually dumped in landfills in many developing countries like Nigeria, have been found to be a valuable source of animal feed, replacing parts of the expensive feed ingredients. Fermented and unfermented cassava (Manihot esculenta Crantz) peels substituted maize in the feed of young broiler chickens. The feed was made by replacing maize content with 40% each of microbially fermented (MFCP), naturally fermented (NFCP), and unfermented cassava peel (UFCP), designated as diets 1, 2, and 3, respectively. The diet containing UFCP served as the control. The birds underwent weekly examinations for abnormalities and body weight gain. At the end of the feeding trial, mortality rate (3.45 %) was recorded only with the chickens fed with UFCP. There was a significant difference (p < 0.05) in the body weight of birds fed with different formulations. The average body weight gain increased from 617.03 g/bird to 2070.15 g/bird, from 615.42 g/bird to 1963.81 g/bird, and from 620.35 g/bird to 1685.11 g/bird, resulting in final body weights of 1453.12 g/bird, 1348.39 g/bird, and 1064.76 g/bird for chickens fed with MFCP, NFCP and UFCP, respectively. The protein efficiency ratio (PER) recorded was greater than 2.0 in all dietary treatments, indicating good quality, with diet one recognized as an excellent protein source. However, birds fed with diets containing fermented peels showed improved feed conversion ratio (FCR) and apparent protein digestibility (APD) compared to birds fed with UFCP formulation. Proximate and anti-nutritional analyses showed that the chemical composition of the fermented peel was superior to that of the control. The results revealed that fermentation significantly (p < 0.05) reduced the phytate and cyanide contents of the cassava peels, which may explain the high mortality rate in birds fed with UFCP.