Studies on the variations in the chemical composition of leucaena (Leucaenaleucocephala (Lam.) De Wit) during ensiling

Abstract

The fermentation quality and nutritive value of leucaena ensiled either as whole forage or separate stem and leaf fractions were investigated. About 10-month-old leucaena (Leucaena leucocephala (Lam.) De Wit.) grown in Okinawa Island, Japan, was used.Samples were chopped to about 4 cm lengths and stuffed into laboratory silos of 1.4-1.5 kg capacity. Samples were taken at 0, 1, 3, 5, 7 and 42 days of ensiling for the laboratory determination of total nitrogen (T-N), volatile basic nitrogen fibre (VBN) expressed as g kg-1 of T-N, neutral detergent fibre (NDF), acid detergent fibre (ADF), cellulose, acid detergent lignin (ADL), in vitro digestibility (IVD), lactic acid, acetic and butyric acid. The leaves had the highest T-N (52 g kg Dm-1)] IVDM (695.6 g kg-1) and lowest cell wall components, while the stem had the lowest T-N (15.8 g kg Dm-1) and IVDM (334.9 k kg Dm-1) but highest cell wall components. However, the whole forage had intermediate values. These differences were significant (P<0.01). The pH of the silages declined with advancing ensiling time but was generally high ( P 35.00) in all three. Although lactic acid was the dominant acid in all fractions, the difference between leaf and stem was significant (P<0.01) but that between either the leaf or stem and, whole forage were not significant (P>0.05). Acetic acid was very low in all and showed no significant difference (P> 0.05) among silages. Ensiling only slightly decreased the IVD and T-N in whole forage and leaves but not in stem.


(Ghana Journal of Agricultural Science, 1996, 29(2): 27-32)