*2.3. Sample Preparation*

Soil samples were dried, ground, and sieved through a 2 mm sieve. Freshly collected samples of forage, silage, and total mixed rations were freeze-dried in a Coolsafe Pro 100-9 system (Labogene, Allerød, Denmark), ground, and stored at room temperature until analysis. Milk was freeze-dried under the same conditions and stored at −80 ◦C until analysis (see Figure 1). Samples were analyzed within a maximum time of six months.
