ABSTRACT Research on the use of heart of palm by-product (HPB) as a feed for dairy cattle is needed since it is a low-cost alternative in addition avoiding environmental contamination. The objective of this study was to evaluate intake, digestibility, milk yield and composition from cows fed HPB. Sixteen Holstein cows were used. Treatments consisted of fresh sugarcane replacement (dry matter basis – DM) of HPB at levels 0%, 7.5%, 15% and 22.5%. Experimental design was randomized blocks with measures repeated in time, and data were compared by linear, quadratic and cubic contrasts. A decreasing linear effect of HPB was observed on DM, organic matter (OM), crude protein and non-fibrous carbohydrates intakes and on digestibility of DM and neutral detergent fibre. A quadratic effect was observed for metabolizable energy intake and OM digestibility. Milk yield and composition were not affected by levels of HPB added to the diet. A cubic effect was detected for fat-corrected milk (FCM) and energy-corrected milk (ECM). HPB is detrimental to intake and digestibility, but the 7.5% replacement level of HPB is recommended depending on the milk production level, since rumen environment was improved, leading to greater FCM and ECM yields at lower production costs.

中文翻译：

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用于泌乳奶牛的棕榈心副产品

摘要 使用棕榈副产品 (HPB) 心脏作为奶牛饲料的研究是必要的，因为它是一种低成本的替代品，同时避免了环境污染。本研究的目的是评估饲喂 HPB 的奶牛的摄入量、消化率、产奶量和成分。使用了十六头荷斯坦奶牛。处理包括 HPB 的新鲜甘蔗替代品（干物质基础 - DM），水平为 0%、7.5%、15% 和 22.5%。实验设计是随机区组，并及时重复测量，并通过线性、二次和三次对比对数据进行比较。观察到 HPB 对 DM、有机物质 (OM)、粗蛋白和非纤维碳水化合物摄入量以及 DM 和中性洗涤纤维的消化率的线性影响下降。观察到可代谢能量摄入和 OM 消化率的二次效应。牛奶产量和成分不受添加到饮食中的 HPB 水平的影响。对于脂肪校正牛奶 (FCM) 和能量校正牛奶 (ECM)，检测到立方效应。HPB 对摄入和消化率有害，但建议根据牛奶生产水平使用 7.5% 的 HPB 替代水平，因为瘤胃环境得到改善，从而以更低的生产成本获得更高的 FCM 和 ECM 产量。