Lactational Performance of Early-Lactation Dairy Cows Fed Forages Produced by Two Different Crop Production Programs

Early-lactation high-producing dairy cows require highly digestible forages. Thirty early-lactation (58 days in milk; 38.9 kg/d milk) cows were blocked and randomly assigned to one of two treatments. The treatments were the control (CON), consisting of corn silage and alfalfa haylage produced via university crop production practices, versus supplementing soil and crop additives (SCA) during crop production. Milk production (32.6 and 36.9 kg/d for CON and SCA, respectively) increased (p < 0.04) when cows were fed SCA forages compared with cows fed CON forages, while the dry matter intakes were similar (p < 0.46). The yields of milk fat were similar (p > 0.26), but the milk protein (0.98 and 1.09 kg/d), lactose (1.62 and 1.88 kg/d), and total solids (3.77 and 4.25 kg/d) contents were greater (p < 0.05) for cows fed SCA compared with cows fed CON. The total-tract apparent neutral detergent fiber (48.5 and 54.7%) and acid detergent fiber (48.3 and 54.4%) digestibility increased (p < 0.03), while the starch digestibility (97.9 and 98.4%) tended (p < 0.06) to increase for cows fed SCA compared with cows fed CON. Feeding highly digestible forages during early lactation improved milk production, milk composition, and fiber digestibility in a high-forage ration.