Tropentag, October 9 - 11, 2007 in Witzenhausen "Utilisation of diversity in land use systems: Sustainable and organic approaches to meet human needs"

Diversification in the Use of the Seeds of Five Soil Nitrogen Enriching Tropical Plants Used on Marginal Lands for Livestock Production

¹University of Ibadan, Department of Animal Science, Nigeria
²Martin Luther University Halle-Wittenberg, Institute of Agricultural and Nutritional Sciences, Germany

Abstract

The seeds of five plants (Enterolobium cyclocarpum, Mucuna pruriens, Centrosema pubescens, Lablab purpereus and Gliricidia sepium) which are normally used for nitrogen enrichment in marginal soils were harvested. Their chemical, antinutritional factor (ANFs) and amino acid compositions were determined. The aim is to promote the use of the seeds for livestock production. Samples of the seeds were sun-dried and milled. A portion of the milled samples was subjected to wet heating by autoclaving. The proximate, mineral, total phenols, tannin, phytic acid, L-dopa, cyanide and amino acid compositions were analysed. The highest crude protein was in G. sepium (498 g kg^-1) followed by M. pruriens with 278 g kg^-1. The lowest crude protein was in M. esculenta with 209 g kg^-1. The crude fibre in E. cyclocarpum was the highest with 131 g kg^-1 while G. sepium and C. pubescens had the lowest crude fibre with 92 g kg^-1 each. Total phenols, tannin and L-dopa were significantly higher in M. pruriens with levels of 30.4, 7.1 and 13.2 g kg^-1, respectively. The highest levels of phytic acid and cyanide were present in G. sepium with 14.8 and 7.6 g kg^-1, respectively. There were remarkable reductions in the levels of the ANFs in the seeds after autoclaving. Of the total phenols 71, 62, 73 and 80% of the total phenols in the M. pruriens, L. purpereus, C. pubescens and G. sepium, respectively was eliminated. Of the essential AAs, the levels of methionine, threonine and lysine in the seeds were lower than reported levels in soy bean meal. The levels of valine, leucine, isoleucine and histidine were comparable to those in soy bean meal. The level of histidine in G. sepium was much higher than in soy bean meal. Based on the FAO/WHO scoring pattern, methionine was the first limiting amino acid in all the seeds.

Keywords: Diversification, livestock production, seeds, soil nitrogen enrichment plants

Contact Address: Eustace Ayemere Iyayi, University of Ibadan, Department of Animal Science, Ibadan, Nigeria, e-mail: eustace.iyayimail.ui.edu.ng