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Optimal utilisation of tannin-rich browse tree fodders including Acacia spp. foliages as crude protein (CP) supplements to ruminants in the tropics is limited by less available information on their feed nutritive potential. Two studies were conducted to: (1) determine rate and extent of ruminal dry matter (DM) degradability (DMD) and (2) investigate effect of sun-dried Acacia nilotica (NLM), A. polyacantha (PLM) and Leucaena leucocephala leaf meal (LLM) supplementation on growth performance of 20 growing (7–9 months old) Small East African male goats (14.6 ± 0.68 kg) fed on native pasture hay (NPH) basal diet for 84 days in a completely randomised design experiment in north-western Tanzania. The goats were randomised into four treatment groups consisting of five animals each. Three supplement diets: 115.3 g NLM (T2), 125.9 g PLM (T3) and 124.1 g LLM (T4), which was used as a positive control, were supplemented at 20% of the expected DM intake (DMI; i.e., 3% body weight) to the three animal groups fed on NPH (basal diet) compared to the animals in a control group that were fed on NPH without browse supplementation (T1). NPH had significantly the lowest (P

Browse tree leaves from six species of Acacia being: A. angustissima, A. drepanolobium, A. nilotica, A. polyacantha, A. tortilis and A. senegal were screened to quantify levels of extractable total phenolics (TEP), extractable tannin (TET) and condensed tannin (CT). The CT in the leaf samples were assayed for soluble, protein-bond and fibre-bound CT using a modified butanol/HCl technique through improved extraction of tannin in leaf samples with aqueous sodium deodocyl sulphate (SDS)-β-mercaptoethanol solution. Effect of tannins on in vitro organic matter digestibility (OMD) was assessed by polyethylene glycol (PEG) tannin bioassay. Forages had variable crude protein (CP) ranging from 176 g/kg DM in A. nilotica to 229 g/kg DM in A. angustissima. A. nilotica had the lowest (P

Growing of trees as woodlots on farms for five to seven years in rotation with crops was considered as a potential technology to overcome the shortage of wood, which is a common problem to many parts of sub-Saharan Africa. The paper summarizes the results of trials conducted at Tabora and Shinyanga in northwestern Tanzania on rotational woodlots, to evaluate tree species for wood production and yields of maize grown in association with and after harvest of trees. On acid sandy soils at Tabora, Acacia crassicarpa A. Cunn. ex Benth. grew fast and produced 24 to 77 Mg ha(-1) of wood in four to five years. On alkaline Vertisols at Shinyanga, seven years old woodlots of Acacia polyacantha Willd. and Leucaena leucocephala (Lam.) De Wit. produced 71 and 89 Mg ha(-1) of wood, respectively. Intercropping of maize between trees was possible for two years without sacrificing its yield. The first maize crop following A. crassicarpa woodlots gave 29 to 113% greater yield than the crop after natural fallow. Acacia polyacantha and L. leucocephala woodlots also increased the subsequent maize yields over a three-year period. The increase in crop yields after woodlots was attributed partly to accumulation of greater amounts of inorganic N in the topsoil compared to the traditional fallow, and partly to other effects. Thus medium-term rotational woodlots are likely to contribute to meet the wood requirements of rural people and thereby help protect the natural woodlands in sub-Saharan Africa.