Lay Summary Precision feeding in dairy farming is a promising approach to improve efficiency by tailoring cow diets to individual needs. In this study, we evaluated how individual dairy cows respond to different dietary supplements over short periods and tested two precision feeding methods that used cows' past performance to predict the best supplement choice. Twenty-four lactating cows were given different high-protein or energy-rich supplements, or no supplement, to determine the effect on their feed intake and milk production. Then, two precision feeding strategies were used to assign supplements: one based on the average past response of each cow, and the other based on changes in their performance over time. During the training phase, cows that received energy and/or protein supplements ate more and produced more milk than cows on the control diet, but they were less efficient in converting feed into milk. During the algorithm testing phase, no improvements in DMI, MY, or FE were observed for either of the two algorithms tested. Importantly, the precision-fed cows did not earn more revenue or reduce feed costs compared to those on a conventional diet. These findings suggest that simple precision feeding, based on short-term past performance, may not be a reliable method for improving productivity or profit. More advanced tools may be needed to realize the potential of individualized feeding in dairy production fully.
Souza et al. (Mon,) studied this question.