42 Advancements in silage management and technology for beef and dairy cattle

Abstract

Abstract In 2017, 2.6 million ha of American farmland were destined for corn silage production, which was estimated at 116.5 million tons. Data for 2018 are yet to be compiled but field observations provide insight of a difficult year for growing and harvesting conditions. In recent years, there has been a renewed interest in making the most efficient use of forage resources. Since corn silage is a predominant forage for beef and dairy cattle, most advances have focused on improving harvesting, storage and feeding methods of this crop. The harvesting process has been modified with the introduction of various designs of kernel processors; commercial laboratory data show a trend towards greater and more uniform processing score since 2010. Furthermore, the degree of processing can now be objectively evaluated by combining hydrodynamic separation and image processing software to obtain a kernel processing score in real time in field conditions. Applications of plastic film technology, such as oxygen barriers, to seal and maintain an anaerobic environment, have aroused interest due to the possibility of reducing spoilage with a concomitant increase in recovery of dry matter from the uppermost layer of a silage pile. Throughout the storage phase, it has been recognized that starch digestibility increases over time due to prolamin solubilization. Recent work with reconstituted high-moisture corn demonstrated that bacterial proteolytic activity contributes 60% to protein solubilization and that fermentation acids play a minor role in this process. The field of inoculants has also seen innovations in terms of application equipment and species and strain selection, with Lactobacillus buchneri becoming relevant for certain conditions that require longer aerobic stability. During feed-out, dry matter monitoring can be done with instant measurements using NIR technology in various applications ranging from tractor-mounted instruments to hand-held devices. Even though silage making has been a longstanding practice, specific aspects of the process have evolved over time and are worthy of consideration to improve forage management and quality in support of ruminant nutrition.