Effect of multipurpose tree (MPT) supplements on ruminal ciliate protozoa

The effect of five multipurpose trees (MPTs), Acacia angustissima, Acacia saligna, Chamaecytisus palmensis, Leucaena pallida and Sesbania sesban on ciliate protozoa was investigated in rumen cannulated Ethiopian sheep. Both entodiniomorphs and holotrichs were counted. The protozoa counts from S. sesban supplemented diet were significantly (P < 0.04) higher than from other diets. Maize stover alone and maize stover supplemented with C. palmensis or L. pallida did not have any significant (P > 0.05) effect on the numbers of ciliate protozoa. A. saligna supplemented diet reduced the numbers of protozoa from 1.60 × 105 to 0.62 × 105 cells ml−1 rumen fluid. Differences in ciliate numbers among other MPT supplements barely failed to reach significance (P < 0.06). Entodiniomorphs dominated (93.3%) the protozoa population in all diets, with Entodinium species being the most predominant (80.7%). None of the MPTs tested eliminated protozoa. Effect of eating S. sesban and placing it in the rumen on protozoa was tested. Protozoa numbers decreased in the sheep in which S. sesban was placed in the rumen while they remained high in the sheep that were allowed to eat the supplement. Relationships between protozoal numbers and in sacco fibre degradation and neutral detergent fibre (NDF) digestibility were also examined. Degradation rate (c) increased with increase in protozoa numbers. NDF digestibility was significantly (P < 0.01) lower in A. saligna supplemented diet than in others. No significant relationship was observed between ruminal pH and protozoal numbers with all diets. The animals on A. angustissima died after 9 and 21 days of the experiment.