Sabrina P. Van den Oever Sabrina P. Van den Oever Katrin Bauer Katrin Bauer Andreas Haselmann Andreas Haselmann Matthias Schreiner Matthias Schreiner Birgit Fuerst-Waltl Birgit Fuerst-Waltl Werner Zollitsch Werner Zollitsch Qendrim Zebeli Qendrim Zebeli Helmut K. Mayer Helmut K. Mayer Wilhelm Knaus Wilhelm Knaus Elsevier 2026 This study aimed to investigate the impact of feeding either silage or hay (harvested from the same parent plant material) on cow's milk composition. Numerous milk constituents (e.g., protein fractions, free amino acids, amines, fatty acid profile, B-vitamins, vitamin E) were analyzed. Results showed that crude protein content was only numerically higher in hay milk compared to silage milk (3.11 and 2.92 %, respectively). Free amino acids showed hardly any differences with values for sum of free essential amino acids of 6.50 and 5.09 mg L−1 for hay milk and silage milk, respectively. For vitamin B1, B2 and B6, no differences were found. Vitamin B12 and vitamin E were significantly higher in silage milk (3.83 μg L−1 and 0.39 mg L−1, respectively) compared to hay milk (2.50 μg L−1 and 0.26 mg L−1, respectively). Fatty acid profile was comparable for both types of milk, and sensory analysis showed only minor differences. PDFDocument eng 2026-07-01T08:29:14.224391135Z 2026 Forage Conservation Hay Milk Silage Milk Protein Fractions Vitamins Fatty Acids Sensory Evaluation 1038740 b application/pdf http://creativecommons.org/licenses/by/4.0/