Cassava waste as an animal feed treatment: past and future

Abstract

In many countries, scientists have developed techniques and processing methods to minimize animal feed waste and costs. The agricultural waste from each part of the cassava plant is rich in macronutrients, essential amino acids, vitamins, and minerals, making it a potential candidate to be used as animal feed. However, the significant content of anti-nutritional properties in cassava, which are linked with the indigestibility of the animal, led to controversy regarding the strategy to use cassava as highly commercialized animal feed. Among the anti-nutritional compounds found in cassava waste, cyanide was found to have the most negative effect on the animals upon feed consumption. Therefore, several strategies to maintain the homeostasis of nutrient and non-nutrient compounds improved the production and commercialization of cassava waste-based animal feed. Physical pretreatment, microbial pretreatment, and fermentation significantly reduced the cyanide content in the cassava waste. In terms of fermentation, solid-state fermentation of moist, solid, non-soluble organic material acts as a nutrient and energy source. Factors such as moisture content, particle size, temperature, pH, media composition, choice of microbial inoculum, and inoculum density were important to increase protein content, improve digestibility, amino acids, enzymes, and vitamins. The impact of using cassava waste as animal feed replacement was significant on the digestibility, growth performance, and changes in blood parameters of the animals. Despite the challenges in nutrient content and biological action, the accessibility and availability of cassava in different geographical areas also pose significant challenges. Therefore, applying technological advancements, particularly in enhancing the nutritional content and biological mechanisms, is important, with the implementation of advanced research and collaboration with industries and other stakeholders.

Graphical abstract