Mupangwa et al., 2003. Livest. Res. Rural Dev., 15 (2):

Cassia rotundifolia (Cassia), Lablab purpureus (Lablab) and Macroptilium atropurpureum (Siratro) were harvested at 8, 14 and 20 weeks of growth and either sun- or oven-dried prior to evaluation by the in sacco technique using three rumen fistulated Friesian steers. The samples were incubated for 6, 12, 24, 48, 72, 96 and 120 h.

After oven-drying the three legumes had similar quickly degradable dry matter contents at each of the growth stages. However, after sun-drying, cassia and lablab had a higher quickly degradable dry matter content than siratro. The quickly degradable dry matter content of the forages declined with increasing maturity, irrespective of drying method.  For the slowly degradable fraction of the dry matter, the rate of degradation was greater for siratro, 0.08/h, than either cassia or lablab that were similar (0.05/h). Sun-dried forages harvested at 14 and 20 weeks of growth had greater potentially degradable dry matter content than oven-dried forages. At all stages of growth and irrespective of drying method, the proportions of potentially degradable dry matter were highest for lablab followed by cassia then siratro.

It is concluded that oven-drying reduced the in sacco dry matter degradability of siratro, cassia and lablab forages compared with sun-drying.