Effectiveness of chopped lucerne hay as a moisture absorbent for low dry‐matter maize silage: Effluent reduction,fermentation quality and intake by sheep

This study determined effects of addition of lucerne hay (LH) as moisture absorbent on effluent reduction, fermentation and subsequent intake of maize (corn) silage by sheep. Treatments included maize forage ensiled without LH (LH0), with 50 g/kg LH (LH5) and with 100 g/kg LH (LH10) on a fresh weight basis. Silages were made in 150‐kg bags in triplicate. Upon opening, representative samples from each bag were taken twice weekly during a feeding trial and used for laboratory analyses in a completely randomized design. Silages were fed ad libitum to six ewes in a duplicated 3 × 3 Latin square design with 21‐day periods for intake and digestibility determination. Lucerne hay incorporation linearly increased DM, ash, water‐soluble carbohydrates, buffering capacity and pH of silages, while it linearly decreased ammonia nitrogen, acetic acid and ethanol concentrations (p < .05). Effluent volume linearly decreased from 33 ml/kg in LH0 to 0.8 ml/kg in LH10. Addition of LH resulted in a linear increase in intakes of organic matter and fibre in ewes, while digestibilities of these nutrients linearly decreased (p < .05). Lucerne hay addition improved fermentation parameters and resulted in increased intake of maize silage without having negative impact on aerobic stability.     

Fermentation and chemical composition of high‐moisture lucerne leaf and stem silages harvested at different stages of development using a leaf stripper

Lucerne (Medicago sativa L.) requires four or more cuttings at early bud stage per growing season to optimize the amount of crude protein and digestible fibre for feeding high‐producing dairy cows. However, there is potential to generate a nutrient‐dense feed from lucerne regardless of developmental stage by harvesting its protein‐rich leaves separate from its fibrous stems. In order to determine whether fractionated lucerne can be effectively ensiled under high‐moisture conditions and be nutritionally competitive with wilted whole‐plant silage, leaf and stem fractions, harvested at three developmental stages (early bud, 10%–20% bloom and >50% bloom), were directly ensiled in mini‐silos. At day 0, 1, 3, 21 and 140 of ensiling, silages were analysed for protein and non‐protein nitrogen fractions as well as their fermentation products and carbohydrate composition. Silages from unwilted leaves and stems were more heterofermentative than wilted whole‐plant silages; their fermentation shifted from primarily lactic acid to acetic acid production after 21 days. In leaf silages, the high degree of protein degradation into non‐protein nitrogen (~55%) was most likely due to fermentation quality. Nevertheless, at 140 days of ensiling, leaf silages had 21%–25% higher (p < 0.01) available protein (peptide amino acids, soluble and insoluble protein) content than wilted whole‐plant silages, regardless of developmental stage. Achievement of a more rapid pH decline and improved fractionation may further increase the nutritional value of leaf silages.