PROXIMATE COMPOSITION, MINERAL CONTENTS AND FATTY ACIDS PROFILE OF SELECTED CROP RESIDUES ACROSS SAVANNAH AGRO-ECOLOGICAL ZONES OF NORTHERN NIGERIA

Abstract

Characterization of the chemical composition of animal feed for major nutrients is one of the most vital considerations in the field of animal nutrition. In this study, the proximate constituents, mineral contents and fatty acid profile of selected crop residues across savannah agro-ecological zones of Northern Nigeria were evaluated. The crop residues were collected using multi-stage sampling techniques where three agro-ecological zones were selected from northern part of Nigeria. One local government area (LGA) was then selected from each zone and nine different forms of cereal and legume crop residues (cowpea hay, cowpea husk, groundnut hay, groundnut shell, maize cobs, maize husk, maize stalk, millet stalk and sorghum stalk) among the common residues used as feedstuffs by farmers were selected from each LGA. The collected samples were processed and analyzed using standard analytical procedures and the data obtained were subjected to analysis of variance (ANOVA). The results indicated that, there is significant (p<0.05) differences among the crop residues in the proximate composition. Maize cobs had the highest dry matter contents (92.99%) and least ash contents of 2.07% and the highest ash content was recorded in cowpea husk (7.56%). Groundnut shell had the highest crude fiber contents (57.29%) and least nitrogen free extracts (33.19%). However, there was no significant (p>0.05) difference among the crop residues in terms of mineral contents except in zinc where significant (p<0.05) difference was observed. Similarly, fatty acids profiles were not significantly (p>0.05) different among the crop residues evaluated. The crop residues are endowed with high nutrients therefore should be fed to ruminants.