Effects of different levels of oxalic acid administration on feed intake and nutrient digestibility in goats

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.

为研究草酸添加对山羊采食量和养分消化率的影响，进行了一项实验。将4只杂交雌性（波尔×本地）山羊（平均体重46.3千克）采用4×4拉丁方设计，随机分配到4种实验日粮中，草酸添加水平分别为0、2.25、4.50和6.75克/只/天。用水稀释的草酸通过注射器每天给实验山羊口服一次，共进行4个实验周期。每个实验周期为21天，其中包括14天对实验日粮的适应期，随后是7天的数据收集期。在整个研究过程中，所有动物均自由采食象草，并每只每天补充300克（鲜重）颗粒状配合饲料。测定了饲料组成、采食量、养分摄入量和养分消化率。干物质（DM）、有机物（OM）、粗蛋白（CP）、中性洗涤纤维（NDF）的摄入量和代谢能随着草酸添加量的增加呈线性下降趋势，6.75克草酸/只/天处理组的值显著（p<0.05）低于对照组（0克草酸/只/天）。草酸添加对干物质、有机物、粗蛋白和中性洗涤纤维的表观消化率没有影响。实验表明，草酸添加可能影响山羊的干物质和养分摄入量，但不影响干物质和养分消化率。