Altering physical properties of wilted alfalfa by impact-shredding processing

Intensive mechanical processing of wilted alfalfa could potentially increase ruminant utilization of alfalfa. A novel forage processing mechanism which combines impact and shredding was used to investigate intensive physical dis-ruption of wilted alfalfa. Physical disruption was quantified by a processing level index (PLI) defined as the ratio of treat-ment leachate conductivity relative to that of an ultimately processed treatment. Utilizing this index, four processing levels defined by the number of passes through the processor were compared to a control treatment of conventionally chopped material. Processing three times through the processing device achieved a PLI of greater than 60%, with the greatest in-crease in PLI occurring in the first pass through the device. Processing reduced particle-size, but 45% to 56% of the material dry mass was greater than 6 mm at the greatest processing level. Processing severely disrupted the mechanical structure of the stems, making them more compliant resulting in 26% to 56% greater compacted density than the chopped control. Processing reduced silage pH and increased fermentation acids compared to the chopped silage, indicating processing improved silage quality.