Influence of substituting roasted soybean (Glycine max) seeds by those of cowpea (Vigna unguiculata) and of the protein level in the diet on the performance of the local-breed guinea fowl in Burkina Faso

Abstract

This study aimed to evaluate the effects of a diet based on roasted seeds of cowpea in substitution of soybeans on the growth performance and profitability of the local-breed guinea fowl. Three hundred 12-day-old fowls were divided into 12 batches. Four iso-energetic diets, incorporating 5% and 10% of roasted cowpea or soybean seeds, respectively, during starting and growing-finishing, were prepared. The protein levels of the diets were 17.5% or 20% for the starter feed, and 15% or 17.5% during growing-finishing. Starter-feed diets were served on days 13−68, and growing-finishing diets on days 69−222. Zootechnical parameters (liveweight, weight gain and feed ingested) were monitored every other week. At the end of the trial, four fowls per batch were slaughtered to evaluate carcass yield and some organs. The economic viability of the different diets was assessed. Incorporation of cowpea roasted seeds did not induce significant differences in any of the parameters studied except for a few parameters of carcass yields. However, the difference in protein levels produced significant differences in favor of the most protein-rich diets for most of the parameters measured. The breeding period of the guinea fowl given the richer diets was reduced by two weeks. Roasted seeds of cowpea can therefore be used in the diet of the local guinea fowl in substitution of soybeans.