Fermentative and nutritional quality of maize silages complemented with apple and molasses

The addition of rejected apples and molasses to corn silage was evaluated on fermentation quality and nutritional composition using four combinations of corn silage and apples (100-0, 75-25, 50-50, 25-75) and three levels of molasses (0, 5 y 10 %) to obtain twelve treatments (100-0-0, 100-0-5, 100-0-10, 75-25-0, 75-25-5, 75-25-10, 50-50-0, 50-50-5, 50-50-10, 25-75-0, 25-75-5 and 25-75-10) using 36minisilos. The pH was reduced with the addition of apples (pH < 3.6), while molasses increased pH by 0.03 - 0.07 units. Ammonia nitrogen was increased (0.59 % to 2.44 %) while VFAs maintained acceptable levels (acetic acid: 0.04 - 0.73 %, propionic: 0.02 - 0.70 %; butyric: 0.0 - 0.58 %), increasing slightly with molasses and decreasing with apples. In comparison to control silage (100-0-0) dry matter and ashes were reduced with the addition of apples and increased with molasses (p < 0.001). Crude protein increased only in mixture 100-0-5 (5.9 vs. 7.5 %). Non-structural carbohydrates increased only with the highest level of apples and molasses (61.3 vs. 66 %). Apples increased NDF (59.5 vs. 63.1 %) and ADF (30.7 vs. 35.6 %), but at 75 % inclusion, both decreased; molasses reduced NDF and ADF always. The cost of digestible dry matter decreased in 75-25-10 ($6.01 to $5.00 kg(-1)) and relative value calculated by Petersens Method increased (96.7 to 115.3 %). Depending on costs and availability, apples and molasses can be used to improve the quality and cost of corn silage.