Bunker silo surface spoilage can have a big impact on animal performance, say Kansas State University researchers.

A small bunker silo and an AgBag were filled with alternating loads of chopped corn. The bunker was sealed after 90 days, and that silage was designated spoiled. The bagged silage was designated normal. The dry matter content, ADF and NDF were 26.4%, 49.0 and 31.0, respectively, for the spoiled silage and 38%, 42.6 and 23.4 for the normal silage.

Steers were fed four 90%-silage diets with the silage portion being 100% normal, 75% normal and 25% spoiled, 50% normal and 50% spoiled, or 25% normal and 75% spoiled. Crude protein digestibility decreased as the percentage of spoiled silage in the diet increased.

The addition of spoiled silage had significant negative effects on dry matter intake and digestibility, with the biggest decrease in digestibility coming with the first increment of spoiled silage.