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Our objective was to assess maize fields in two growing seasons to determine the factors that affect the yield and nutritive value of maize silage produced in Brazil. Seventy‐four commercial maize fields, 49 in the first growing season (FGS) and 25 in the second (SGS), were sampled over two crop years. In each field, 12 linear meters of plants were cut by hand at 25 cm above ground. Characteristics of the field, plants, and their components (stalk, leaves, husk, cob, and grains) were evaluated. Farmers were interviewed regarding the crop management practices applied. Chopped maize forage was dried to assess its chemical composition, in vitro dry matter digestibility, and in vitro fibre digestibility. Descriptive statistics was carried out for agronomic and nutritional variables. To determine the factors that affected yield and nutritive value in maize fields, artificial neural networks were used. The dry matter yield (DMY), NDF concentration, starch concentration, NDF digestibility, and DM digestibility were chosen as response variables. Then, the top 10 main parameters were used to explain the results. Overall, the association between grain and stover yield maximized DMY. Plant population (plants/ha) and plant maturity were also important to explain yield. Grain depth and number of grains per row were the two most important parameters linked to genetic traits. Plant maturity was decisive in altering the nutritive value of forage maize. Maize grown in the FGS had both greater yield and nutritive value than maize in the SGS. [ABSTRACT FROM AUTHOR]

This study determined the effectiveness of two Lactobacillus buchneri strains (commercial and indigenous) and sodium benzoate ( SB) in improving the aerobic stability of corn silage under laboratory and field conditions. Two experiments were carried out to test the following treatments: untreated forage, commercial L. buchneri ( CLB), indigenous L. buchneri ( ILB) and SB at a 2 g kg−1 concentration. Both inoculants were applied at a rate of 1 × 106 colony forming units of bacteria per gram of forage. In experiment 1, five replicates of each treatment were ensiled in 15-L laboratory silos. The nutritional, fermentation and microbiological characteristics and aerobic stability of the silage were determined. In experiment 2, the top of a bunker silo was divided into four parts (blocks) along its length before it was sealed, and the treatments were randomly applied. Three bags were buried in each experimental unit (two at the top and one at the core) to determine the loss of dry matter ( DM) and the silage characteristics. In experiment 1, ILB exhibited a lower lactic acid concentration and higher 1,2-propanediol and acetic acid levels, which provided intermediate aerobic stability (67 h). In both experiments, treatment SB exhibited higher residual water-soluble carbohydrate levels and longer aerobic stability relative to the other treatments. In experiment 2, there were lower DM losses and higher digestibility coefficients when SB was applied, similar to that found at the core. Overall, SB was the most effective additive for improving fermentation, preserving nutrients and reducing the aerobic deterioration of corn silage at the top of a bunker silo in a hot-climate environment. [ABSTRACT FROM AUTHOR]