G. Borreani, Ernesto Tabacco
The paper critically reviews the history of silage sealing and discusses the steps that have been taken to develop integrated silage sealing strategies. Particular emphasis has been placed on the recent advances that have been made in plastic materials, management practices, and operational protocols with the aim of achieving the most hermetic environment possible to avoid air penetration and contact with the silage mass during silage conservation and feed-out. Sealing strategies and the quality of the sealing materials have been identified as the key factors in excluding air from silage and ensuring its proper preservation over time in farm silos. Reducing DM and nutritional losses and keeping the microbial quality of silage uniform in the different parts of the front face of horizontal silos during feed-out helps farmers improve the efficiency and sustainability of livestock farms. Recently developed advanced sealing strategies and good management practices reduce DM losses, even in peripheral areas of a silo, and lead to a great improvement in the uniformity of the silage microbiology from the top to the bottom of silos. The present review presents the advanced sealing strategies that are now available for implementation at a farm level to obtain zero visible and non-visible spoiled silage, as well as a high uniform microbial quality of the working face.