Effect of molasses on the fermentation quality of wheat straw and poultry litter ensiled with citrus pulp

Abstract

In a 4 2 factorial design, mixtures of wheat straw, poultry litter and citrus pulp with 0 and 5% molasses [T1 (75:25:0), T2 (60:25:15), T3 (45:25:30), and T4 (30:25:45)] were ensiled for a period of 60 days in 20 L laboratory silos. Inclusion of 5% molasses had no significant (P>0.05) effect on pH, neutral detergent fibre, acid detergent fibre, acid detergent lignin contents and in vitro organic matter (OM) degradability. However, molasses decreased (P<0.05) the concentration of volatile fatty acids including N-butyric acid. Coliforms were completely eliminated in all treatments, except in the silage without either molasses or citrus pulp. There was a difference (P<0.05) in titratable acidity levels between silage with 0 and 5% molasses. There was a decrease (P<0.001) in silage pH as the proportion of citrus pulp in silage increased from 0 to 30%. In vitro OM degradability increased (P<0.001) from 0.33 to about 0.56 as citrus pulp was increased from 0 and 45%. It is concluded that when silages are based on wheat straw and poultry litter, inclusion of molasses ensures favourable fermentation. However, in the presence of citrus pulp there was no additional benefit to the use of molasses.