Evaluation of silage additives and fermentation characteristics of maize forage using laboratory and field scale silo

Abstract

Introduction Successful preservation of forage crops as silage depends on the production of sufficient amount of organic acids in the right ratio to inhibit the activity of undesirable microorganisms under anaerobic conditions (Muck, 2012). During feed out silage exposed to air would cause rapid yeast proliferation, the rapid rise in temperature and decline in sensory and nutritive quality (Dolci et al., 2011). This study was aimed to determine and to compare fermentation characteristic, microbial population and aerobic stability of inoculated maize forage ensiled in laboratory-scale and big bale silos. Material and Methods Whole crop maize (Zea mays L.) was harvested at dough line stage adjusted to achieve a 10 mm theoretical cut length and packed immediately into 1.2 m diameter × 1.2 m height round bales using equipment Göweil LT-Master (GÖWEIL Maschinenbau GmbH, Germany) and into a 3 L laboratory mini silo.Maize forage was either untreated (T1) or treated with the bacterial silage inoculant SiloSolve FC containing Lactococcus lactis DSM 11037/1k208 and Lactobacillus buchneri DSM 22501/1k20738 (50:50) at 1.5 × 10-5 colony forming units g-1 (cfu g-1) of herbage (T2). Big bales and laboratory silos remained undisturbed for120 din farm and laboratory conditions, respectively. For each treatment five big bales chosen at random and five laboratory silo were sampled for chemical and microbial analyses and five were designated for aerobic stability test. Samples were analyzed for the DM content, nutrient content and fermentation parameters as well as pH, silage acids (lactic, acetic, butyric and propionic acids), alcohols and ammonia, and lactobacilli, yeast and mould number. From bales designated for exposure to air for 39 d were removed plastic cover and each bale was fitted with two thermocouple wires. For aerobic stability test on the laboratory scale, a 1000 g sample from each mini-silo was loosely place. [...].