Avaliação da silagem de grão de milho moído reidratado com água e níveis de soro de leite.

Abstract

Ensiling corn improves its nutritive value compared to dry grain, reduces losses, and prevents material deterioration. Whey milk is an alternative additive for rehydrating ground corn grain, as it is rich in soluble proteins, lactose, minerals, and lactic acid bacteria, characteristics that can improve silage quality. Therefore, an experiment was developed to test whey milk as a wet additive compared to water using a completely randomized design with five replicates. The treatments corresponded to the rehydration method of the ground corn grain, with the control being rehydrated with water (adding 30% water to the natural matter of the corn grain in relation to its weight), and three rehydrations with whey milk (adding 20, 30, and 40% whey milk to the natural matter of the corn grain in relation to its weight). To characterize the silage quality, the silages were opened after 90 days and analyzed for the following variables: losses, pH, ammoniacal nitrogen, organic acid content, microbiological population determination, chemical composition, degradability, and aerobic stability. The highest effluent loss was observed in the treatment with 40% whey milk rehydration in the natural matter (MN; 7.86 kg t-1 DM). The pH was higher in the water-rehydrated treatment (5.51). For total soluble carbohydrates, it was observed that rehydration using whey milk with 20, 30, and 40% increased its concentration. Silages rehydrated with water had the lowest lactic acid bacteria population (0.90 Log/CFU/g) and the highest yeast and enterobacteria populations, being 3.74 and 0.86 Log/CFU/g, respectively. The lowest lactic acid concentration was observed in the water-rehydrated silage, being 2.71 g/kg DM. It was observed that treatments rehydrated with 20 and 30% whey milk in MN had the highest degradability rates, being 91.76 and 90.75%, respectively. The breakdown of stability occurred more rapidly in the water-rehydrated treatment and in the treatment with 40% whey milk rehydration in MN, occurring at 41.6 and 46.4 hours, respectively. Rehydration using 20% whey milk presented better benefits to ground corn grain silage when compared to rehydration with water and other levels.