R. D. Shaver , Ph.D.Harvest and storage of high-quality cornHarvest and storage of high-quality corn silage for dairy cowssilage for dairy cowsRandy Shaver, Ph.D.Department of Dairy Science University of Wisconsin - Madison University of Wisconsin - ExtensionR. D. Shaver , Ph.D.Corn SilageCorn SilageNormally high-energy forage cropHigh DM yield per acre Often provides major portion of forage inventoryR. D. Shaver , Ph.D.Variation in corn silage nutritive valueVariation in corn silage nutritive valueProportion of grain vs. stalk, cob, and leavesNDF content of stalk, cob, and leavesDigestibility of NDFStarch content of grainDigestibility of starchOil contentProtein contentR. D. Shaver , Ph.D.Factors affecting corn silage nutritive valueFactors affecting corn silage nutritive valueHybridStage of maturity at harvestWhole-plant (WP) moisture contentHeight of CuttingChop lengthCrop processingSilage-making practicesR. D. Shaver , Ph.D.Stage of MaturityStage of MaturityR. D. Shaver , Ph.D.Kernel Milk-Line PositioningKernel Milk-Line PositioningRelationship with WP moisture content too variable to be a reliable trigger for harvestUsed as an indicator of when to start monitoring WP moisture contentTrigger for corn silage harvest is WP moisture contentR. D. Shaver , Ph.D.WP Moisture ContentWP Moisture ContentR. D. Shaver , Ph.D.Recommended WP moisture content at harvestRecommended WP moisture content at harvest65% to 70%R. D. Shaver , Ph.D.Harvest at 70% WP moistureHarvest at 70% WP moisture seepage losses acidity estimated Milk per tonSimilar estimated Milk per acreLess soil erosion and silage nitrate concernsPrioritize needs for maximum crop yield vs. high quality to determine best cutting heightR. D. Shaver , Ph.D.Chop LengthChop LengthR. D. Shaver , Ph.D.Recommended chop lengthRecommended chop length Conventional harvesterConventional harvester.95 cm TLC- Range: .64 to 1.27 cm TLC - Varies with moisture content, hybrid, & harvester - Breakage of cobs and kernels - 5% - 10% on top screen of PSU-Nasco boxR. D. Shaver , Ph.D.Recommended chop lengthRecommended chop length Harvester fitted with crop processorHarvester fitted with crop processor1.91 cm TLC- 15% to 25% on top screen of PSU-Nasco box - 1.27 cm TLC when WP moisture 95% Kernel breakage and no cobs 1/8th ring Ruminal and total tract starch digestion Milk yield & fat % Aerobic stability on face & during feed-outEnzymes - Expensive & not needed on corn silageMolasses or sugars - Normally not needed on corn silageR. D. Shaver , Ph.D.Microbial inoculants for corn silageMicrobial inoculants for corn silageFermentation improved only 40% of time in research trials with CS vs. 70% with ASHard to improve upon natural fermentation of high LA & low pH typically seen with CSSilo DM loss 2% units Aerobic stability on face & during feed outCost variable, but $1.20 per treated ton in USSafety & handling precautionsUrea not an effective preservativeR. D. Shaver , Ph.D.Propionic AcidPropionic AcidCommercially-available propionic-acid based products usually with some acetic acid or benzoic acidBuffered products that are non-corrosive Aerobic stability on face & during feed outApplication Rate: 2 kg per ton as-fed CSCost: $4.00 per treated ton in US-usually too expensiveMore often used as TMR additive to improve bunk lifeR. D. Shaver , Ph.D.Silo face managementSilo face managementRemove silage evenly across the faceRemove minimum of 15 cm of silage from face each dayKeep face even & tightly packedFeed up any loose silage