Energy, protein, dry matter and water gap analysis in dairy cows kept under cut and carry fodder- based feeding system.

here is a gap in dry matter, water, energy and protein intake of dairy cows kept in cut and carry fodder-based feeding systems in Sub-Saharan countries, Rwanda included. Data on feed characterization were computed using the FarmDESIGN models by Groot and Oomen (2016), while data on cows’ production requirements were calculated using LIGAPS dairy models. Data were analyzed using a general linear model (GLM) in SPSS. Results on feed characteristics showed that the average nutritive value of the offered fodder was 25% dry matter (DM), 58.5% neutral detergent fibre (NDF), 9.8% crude protein (CP), and 6 MJ of metabolizable energy (ME) per kg DM. The average daily feed intake was 9 kg DM, 35 litres of water, 898 g of CP, and 55 MJ of ME, resulting in milk production of 8.8 litres per day across both sites. However, the average requirement for maintaining a dairy cow with a body weight of 430 kg and a target milk production of 16.5 litres per day was 15 kg of DM, 57 Litres of water, 1907 g of CP, and 137 MJ of ME. This resulted in daily deficits of 6 kg DM, 21.6 litres of water, 1,094 g of CP, and 83.7 MJ of ME, along with a 7.6-litre shortfall in daily milk yield. Available fodder in the dry season is low in quantity and quality for sustaining maintenance and milk production and measures of storing enough fodders that are of good quality are much needed. These findings will be used by researchers in developing dairy diet models at the household level. For dairy feed manufacturers, this analysis will guide proper rationing of high-concentrate ingredients rich in energy and protein, in line with cows’ nutritional requirements. Identifying the gap in available feed resources will encourage farmers to adopt effective feeding management practices that enhance energy, protein, and water intake leading to improved milk production在包括卢旺达在内的撒哈拉以南非洲国家，采用刈割搬运型饲喂体系的奶牛，其干物质、水分、能量及蛋白质摄入存在显著缺口。本研究中，饲料特性数据由Groot与Oomen（2016）提出的FarmDESIGN模型计算生成，奶牛生产需求数据则通过LIGAPS奶牛模型测算得到。数据分析采用SPSS软件中的一般线性模型（General Linear Model, GLM）完成。饲料特性分析结果显示，供试饲料的平均营养指标为：干物质（Dry Matter, DM）占比25%、中性洗涤纤维（Neutral Detergent Fibre, NDF）58.5%、粗蛋白（Crude Protein, CP）9.8%，每千克干物质的代谢能（Metabolizable Energy, ME）为6兆焦。试验两地的平均日均采食量为：干物质9千克、水分35升、粗蛋白898克、代谢能55兆焦，对应日均产奶量为8.8升。然而，体重430千克、目标日均产奶量16.5升的奶牛，其维持代谢与产奶的平均营养需求为：干物质15千克、水分57升、粗蛋白1907克、代谢能137兆焦。据此计算，奶牛每日存在如下营养与产奶缺口：干物质6千克、水分21.6升、粗蛋白1094克、代谢能83.7兆焦，日均产奶量缺口达7.6升。旱季可获取的饲料在数量与品质上均无法满足奶牛维持代谢与产奶需求，因此亟需建立优质饲料的足量储备机制。本研究结果可为研究者开发家庭农场层面的奶牛日粮模型提供参考；对于奶牛饲料生产商而言，本分析可指导其根据奶牛营养需求，合理配比富含能量与蛋白质的高精料原料。明确现有饲料资源的供需缺口，将有助于激励养殖户采用高效饲喂管理措施，提升能量、蛋白质与水分摄入水平，进而改善奶牛产奶性能。