Submitted to: Hoard's Dairyman
Publication Type: Trade Journal
Publication Acceptance Date: 3/24/2006
Publication Date: 5/21/2007
Citation: Rotz, C.A. 2007. Storage can make or break a harvest. Hoard's Dairyman. 152(10):379.
Interpretive Summary: An interpretive summary is not required.
Technical Abstract: Once a dry hay crop is stored, respiration of microorganisms such as bacteria, fungi, and yeasts causes heating and further dry matter (DM) and nutrient loss during storage. Similar loss occurs in all sizes and types of bales stored in a shed. More heating occurs as hay density goes up, particularly in large bales. Dry matter loss during storage in a shed varies from 3 to 9% increasing with hay moisture content. For hay with more than 25% moisture, excessive loss and even spontaneous combustion can occur. Unprotected hay stored outside experiences this same loss plus an additional loss from weathering on the exposed bale surface. Loss in large round bales stored outside varies widely, ranging from 6 to 30%. Lost DM is protein and other highly digestible nutrients. Silage DM losses generally range from 5 to 15% depending on the type of silo used and other management practices. This loss again comes from the most nutritious portions of the forage. Much of the crop protein is converted to non protein nitrogen, which has less value to the animal. These quality changes can reduce the intake and production of animals consuming the forage. Some hay preservative and silage additive treatments can be used to reduce these losses, but the benefits received are normally small and inconsistent.