Author(s): Aganga AA, CM Tsopito, T AdoglaBessa
Four separate studies were conducted to evaluate the feed value of indigenous browses of Botswana. In the first study, browse seeds from nine Acacia species were analysed for proximate composition and in vitro dry matter digestibility. Nutrient composition of the seeds varied, crude protein content of Acacia robusta was 12.52 p.100 while Acacia erubescens was 21.82 p.100. The second study was to evaluate the influence of processing on fibre content and in vitro digestibility of seeds from five browse species using three physical forms of the seeds namely whole seeds, coarsely ground and finely ground. Physical forms of the seeds affected the neutral detergent fibre, acid detergent fibre and dry matter digestibility of all seeds evaluated. The third study was to evaluate the tannin content and crude protein degradation of leaves and twigs from indigenous Acacia species in Botswana rangelands. Correlation between crude protein was found to be negative (-0.582). The fourth study was a feeding trial lasting 98 days using 12 yearling Tswana malegoats fed buffalo grass hay as basal diet and Acacia fleckii or Acacia tortilis as supplements and lucerne to the control group to evaluate animal performance on these browses. Average daily dry matter intake of goats on Acacia fleckii as supplement was 768.40 g and 790.79 g for those on Acacia tortilis as supplements. The average daily body weight gain was higher for goats on lucerne 81 g compared to 72 g and 76 g for those on Acacia fleckii and Acacia tortilis as supplements respectively. Goats fed on the Acacia species consumed the leaves, twigs and even the thorns leaving only the stalks.