Growth performance of broiler chickens fed diets containing shea nut (Vitellaria paradoxa, Gaertn.) meal fermented with Aspergillus niger.

Shea nut meal is a by-product of the shea fat industry in West Africa. The objective was to determine the effect of shea nut meal fermentation using Aspergillus niger on growth performance of broiler chickens. An expeller shea nut meal was fermented in a closed plastic container for 8 d after the addition of 0.25 g of A. niger spores per kg of shea nut meal in 2 parts of water. Each of the 2 shea nut meal samples (the unfermented and fermented meals) replaced wheatfeed in a control diet at 100 g/kg and fed to 128 Ross 308 male broiler chickens (22 to 36 d). There were 8 replicates per diet (2 shea nut meal samples and the control wheatfeed diet) and 4 birds per replicate in cages (0.6 m x 0.6 m x 0.9 m). Analysis of variance of data was used to compare the treatment means. The fermentation method reduced the concentrations of total soluble phenolics (21.9%), bound plus soluble proanthocyanidins (34.5%), soluble proanthocyanidins (24.7%), and hydrolysable tannins (52.9%) in the shea nut meal. Broilers fed the fermented meal exhibited higher (P < 0.001) growth performance than those fed the unfermented meal. However, the growth performance of broilers fed each of the shea nut meal-based diets was lower (P < 0.001) than that of broilers fed the control diet. Mean live weight gain of broilers fed the fermented shea nut meal diet was 82% of that of broilers fed the control diet. The fermentation of shea nut meal using A. niger has the potential to improve the nutritive value of shea nut meal for poultry, but requires further development.