An experiment was carried out to investigate the effects of oxalic acid administration on feed intake and nutrient digestibility in goats. Four female cross bred (Boer × local) goats (average body weight of 46.3 kg) were randomly assigned to four experimental diets including oxalic acid administration at levels of 0, 2.25, 4.50 and 6.75 g/animal/d in a 4×4 Latin Square design. Oxalic acid diluted with water was administered orally via syringe to experimental goats once daily for four experimental periods. Each experimental period was lasted 21 d in length, comprising 14 d of adaptation to the experimental diet followed by 7 d of data collection. All the animals were individually fed with Napier grass ad libitum supplemented with 300 g (fresh basis) pelleted compound feed per goat per day throughout the study. Feed composition, feed intake, nutrient intake and nutrient digestibility were determined. Intakes of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre (NDF) and metabolisable energy tended to linearly decrease with the increasing rate of oxalic acid administration, with the value in the 6.75 g oxalic acid/animal/d treatment being significantly (p<0.05) lower than the control (0 g oxalic acid/animal/d) treatment. The oxalic acid administration had no effect on apparent digestibilities of DM, OM, CP and NDF. The experiment demonstrated that oxalic acid administration may influence in the DM and nutrient intakes, but not influence on DM and nutrient digestibilities in goats.
The effects of palm kernel cake (PKC) as a protein source in a concentrate diet (comprising 35 % crushed maize, 30 % rice bran, 32 % PKC, 2 % vitamin mineral premix and 1 % salt) were examined on intake, live weight (LW) gain and digestibility in female goats (average LW of 12.4 ± 2.6 kg). Four goats were randomly allocated to each of the four treatment diets: (a) Napier grass (Pennisetum purpureum) offered ad libitum (T1), (b) T1 + concentrate at 0.5 % of LW (T2), (c) T1 + concentrate at 1.0 % of LW (T3) and (d) T1 + concentrate at 2.0 % of LW (T4). A 7-day digestibility trial and an 82-day growth experiment were conducted. No differences were observed among diets for intakes of roughage dry matter (DM), total DM, organic matter (OM) and neutral detergent fibre (NDF). The crude protein (CP) intake increased (P 0.05) among treatments. The digestibility of dietary NDF decreased (P 0.05) difference between T2 and T3 diets. Supplementing a basal diet of Napier grass with PKC-based concentrate improved CP intake and LW gain. The PKC-based concentrate diet can therefore be exploited for the use of local feed resources for goat production; however, further research is required to achieve the best growth response.