The effect of nitrogen fertilization on the quality of Kikuyu silage

Abstract

Small‐scale laboratory silos were used to study the fermentation process of Kikuyu (Pennisetum clandestinum Hochst) silage prepared from grass grown at three nitrogen fertilizer levels (300, 400 and 500 kg N/ha/year). Kikuyu grass was cut at three and six‐week growth stages. High nitrogen levels appeared to improve the nutritional value of Kikuyu silage, since increasing nitrogen was associated with an increase in the number of lactic acid bacteria, an increase in acetic acid and lactic acid concentrations and in a decrease in butyric acid content and number of Enterobactcriaceae. The nitrate content at early fermentation was associated with low levels of acetic acid and ammonia and high concentrations of lactic acid in the silage at the end of fermentation. The improvement in silage preservation with increments of nitrogen fertilizer was generally small and not always statistically significant.