Department of Animal and Dairy Sciences, University of Wisconsin, Madison 53706.
Zoetis, Kalamazoo, MI 49007.
J Dairy Sci. 2021 Aug;104(8):8765-8782. doi: 10.3168/jds.2020-20051. Epub 2021 Apr 23.
Predicting dry matter intake (DMI) and feed efficiency by leveraging the use of data streams available on farm could aid efforts to improve the feed efficiency of dairy cattle. Residual feed intake (RFI) is the difference between predicted and observed feed intake after accounting for body size, body weight change, and milk production, making it a valuable metric for feed efficiency research. Our objective was to develop and evaluate DMI and RFI prediction models using multiple linear regression (MLR), partial least squares regression, artificial neural networks, and stacked ensembles using different combinations of cow descriptive, performance, sensor-derived behavioral (SMARTBOW; Zoetis), and blood metabolite data. Data were collected from mid-lactation Holstein cows (n = 124; 102 multiparous, 22 primiparous) split equally between 2 replicates of 45-d duration with ad libitum access to feed. Within each predictive approach, 4 data streams were added in sequence: dataset M (week of lactation, parity, milk yield, and milk components), dataset MB (dataset M plus body condition score and metabolic body weight), dataset MBS (dataset MB plus sensor-derived behavioral variables), and dataset MBSP (dataset MBS plus physiological blood metabolites). The combination of 4 datasets and 4 analytical approaches resulted in 16 analyses of DMI and RFI, using variables averaged within cow across the study period. Additional models using weekly averaged data within cow and study were built using all predictive approaches for datasets M, MB, and MBS. Model performance was assessed using the coefficient of determination, concordance correlation coefficient, and root mean square error of prediction. Predictive models of DMI performed similarly across all approaches, and models using dataset MBS had the greatest model performance. The best approach-dataset combination was MLR-dataset MBS, although several models performed similarly. Weekly DMI models had the greatest performance with MLR and partial least squares regression approaches. Dataset MBS models had incrementally better performance than datasets MB and M. Within each approach-dataset combination, models with DMI averaged over the study period had slightly greater model performance than DMI averaged weekly. Predictive performance of all RFI models was poor, but slight improvements when using MLR applied to dataset MBS suggest that rumination and activity behaviors may explain some of the variation in RFI. Overall, similar performance of MLR, compared with machine learning techniques, indicates MLR may be sufficient to predict DMI. The improvement in model performance with each additional data stream supports the idea of integrating data streams to improve model predictions and farm management decisions.
利用农场可用的数据流预测干物质采食量 (DMI) 和饲料效率可以帮助提高奶牛的饲料效率。残留饲料采食量 (RFI) 是在考虑到身体大小、体重变化和产奶量后,预测和观察到的饲料采食量之间的差异,因此它是饲料效率研究的一个有价值的指标。我们的目标是使用多元线性回归 (MLR)、偏最小二乘回归、人工神经网络和堆叠集成,结合牛描述性、性能、传感器衍生行为 (SMARTBOW; Zoetis) 和血液代谢物数据,开发和评估 DMI 和 RFI 预测模型。数据来自泌乳中期的荷斯坦奶牛 (n = 124; 102 头经产,22 头初产),分为 2 个重复,每个重复持续 45 天,自由采食。在每种预测方法中,按顺序添加 4 个数据流:数据集 M(泌乳周、胎次、产奶量和奶成分)、数据集 MB(数据集 M 加上体况评分和代谢体重)、数据集 MBS(数据集 MB 加上传感器衍生行为变量)和数据集 MBSP(数据集 MBS 加上生理血液代谢物)。使用 4 个数据集和 4 种分析方法对 DMI 和 RFI 进行了 16 次分析,使用研究期间在牛个体内平均的变量。使用所有预测方法为数据集 M、MB 和 MBS 构建了使用每周平均数据在牛个体内和研究内的额外模型。使用决定系数、一致性相关系数和预测均方根误差评估模型性能。所有方法的 DMI 预测模型性能相似,使用数据集 MBS 的模型性能最佳。最佳的方法-数据集组合是 MLR-数据集 MBS,尽管有几个模型的性能相似。每周 DMI 模型的性能最好,使用 MLR 和偏最小二乘回归方法。数据集 MBS 模型的性能比数据集 MB 和 M 稍好。在每个方法-数据集组合中,在研究期间平均的 DMI 模型的性能略高于每周平均的 DMI 模型。所有 RFI 模型的预测性能都很差,但当将 MLR 应用于数据集 MBS 时,RFI 模型的性能略有提高,这表明反刍和活动行为可能解释了 RFI 变化的一部分。总的来说,与机器学习技术相比,MLR 的相似性能表明,MLR 可能足以预测 DMI。随着每个附加数据流的增加,模型性能的提高支持了整合数据流以提高模型预测和农场管理决策的想法。