Abstract
Leaves of three tree legumes, Calliandra calothyrsus (C), Paraserianthes falcataria (F), and Gliricidia sepium (G), were harvested and divided into two portions for oven drying (OD) or freeze drying (FD) resulting in six experimental treatments: COD, CFD, FOD, FFD, GOD, and GFD. The initial solubility, disappearance rate, and extent (undegraded portion) of in sacco dry matter disappearance (DMD) was calculated by a non-linear model using DMD values from ruminal incubation times of 0, 12, 24, 48, and 96 h. Initial solubility was higher (P < 0.01) in CFD than COD and lower (P < 0.07) in FFD than FOD, with G. sepium showing no difference. Disappearance rate was not affected by drying treatment. However, disappearance rates for GOD (0.13 h-1) and GFD (0.14 h-1) were higher (P < 0.001) than for FOD (0.06 h-1) and FFD (0.08 h-1). Both COD and CFO had a slow disappearance rate (0.02 h- 1). Freeze drying resulted in lower (P < 0.001) undegraded dry matter (DM) in both CFO and FFD than in OD material while undegraded DM for G. sepium was not affected by drying method. The use of oven-dried tree legume samples for digestibility estimation may underestimate their feeding value.
