DAKOTA GOLD® RESEARCH
Distillers grain protein quality for ruminants
from "Feedstuffs"; authors: Kevin Herrick and Fernando Diaz-Royon
With the volume and growth rate of distillers grain production, it comes as little surprise that we are discussing distillers grain nutrition. However, what may be surprising is how much variability there actually is in distillers grains and how this may be affecting livestock diet formulation. One concern for livestock nutritionists when feeding distillers grains is the quality of protein and, specifically, the effect the drying process has on protein digestibility.
A few studies have investigated distillers grain protein quality for the ruminant animal. Using ruminally cannulated dairy cows, South Dakota State University researchers (Kleinschmit et al., 2007) evaluated several sources of dried distillers grain with solubles (DDGS) for their ruminal and intestinal disappearance characteristics. As ten years have passed since the ruminally cannulated dairy cow protein disappearance data was obtained, we recently submitted nine samples of DDGS to a commercial laboratory to be analyzed for ruminal and intestinal degradability using the Ross method. We could then compare the Kleinshmit et al., 2007 data, the recently obtained Ross method data, and the data published in the NRC (2001).
DDGS offers an economical source of protein and energy that can be effectively used in diet formulations. The large supply of DDGS as well as the differences among ethanol biorefineries have created co-products with a lot of variability. In order to effectively use DDGS in diet formulations, nutritionists need to recognize these differences and adjust accordingly. Fortunately, advances in feed evaluation methods have made this information easier to determine.