Interpretive Summary: Effect of chemical and biological preservatives and ensiling stage on the dry matter loss, nutritional value, microbial counts, and ruminal in vitro gas production kinetics of wet brewer’s grain silage

By: Marjorie A. Killerby, Saulo T. R. Almeida, Rachel Hollandsworth, Bianca C. Guimaraes, Angela Leon-Tinoco, Lewis B. Perkins, Darren Henry, Thomas J. Schwartz, and Juan J. Romero

Wet brewer’s grain (WBG) is the most abundant byproduct in the manufacture of beer and its rich nutritional composition makes it a valuable feed for cattle. However, WBG is highly susceptible to spoilage so the application of cost-effective preservatives may be a viable approach to prevent nutrient losses during ensiling and feed out. The present study evaluated the effects of chemical and biological preservatives on the nutritional composition and in vitro fermentation and gas production of WBG across three silage production stages: fresh, ensiled, and aerobically exposed silage (AES). Preservatives tested were propionic acid, a bacterial inoculant, and sodium lignosulfonate (NaL) applied at 1% and 2%. Propionic acid successfully reduced the loss of nutrients and preserved more sugars and starch than all other treatments during ensiling, which resulted in higher digestibility in vitro. However, due to its greater concentration of digestible nutrients, ensiled WBG treated with propionic acid also suffered extensive spoilage in the AES. All other treatments failed to improve the preservation of ensiled or AES WBG, but NaL at 2% prevented the decrease of digestibility for AES.

Read the full article on the Journal of Animal Science.