Effect of storage time and use of additives on the quality of grape pomace silages

The objective was to evaluate the chemical and fermentative characteristics of moist grape pomace, treated with additives and ensiled for different times. Samples of wet grape pomace were treated by addition of urea (5 and 10 g/kg of NM) or with enzymatic‐bacterial additive (0.2 and 0.4 g/kg NM). Samples were analyzed for pH, ammoniacal nitrogen, buffer capacity, and chemical composition. For CP, an increasing linear behavior was observed with values between 111.3 and 131.6 g/kg of DM, on Days 0 and 96. The NFC and pH had the lowest values shortly after silo closing, indicating intensification of fermentation. The addition of urea promoted an increase in CP contents, reduction in TCHO and NFC contents, and elevation of IVDMD and N‐NH3 contents. Wet grape pomace exhibits favorable characteristics for feeding ruminants, with silage being a good alternative for its storage. Practical applications Grape pomace is a fibrous food with satisfactory quantities of residual sugars, it meets the desirable characteristics for conservation in the form of silage for later use in animal feed, mainly ruminant herbivores. The silages showed good quality fermentative and chemicals as an increasing linear behavior of crude protein. Wet grape residue exhibits favorable characteristics for feeding ruminants, with silage being a good alternative for its storage can improve this food, especially with respect to the quality of the fibers.