Jack bean (Canavalia ensifomis L. DC) in poultry diets: antinutritional factors and detoxification studies – a review

Abstract, World's Poultry Science Journal, 2007

A review is given on the effects of the inclusion of Jack beans (Canavalia ensifomis L. DC) in poultry diets. Their use is restricted by the presence of a number of antinutritional factors which affect performance when consumed by poultry. The principals of these are identified as concanavalin-A (a lectin), canavanine and canaline (so-called non-protein amino acids), urease and saponins. The mechanisms of their toxicity and the rationale behind the methods that have been used to detoxify Jack beans are described. These mainly involve heat processing, but other approaches such as ensiling, fermentation and addition of chemicals have been applied. It is concluded that, although substantial improvements in nutritional value can result from a number of such treatments, processed Jack beans still contain a residual toxic component which results in depressions in growth rate, food intake and food conversion efficiency when they are included in poultry diets.