In recent years, corn oil extraction has become standard in the ethanol industry resulting in changes in coproducts.  However, advancements in technology have surpassed oil extraction and moved towards fiber extraction methods with one of the first methods being Cellerate™ (Quad County Corn Processors, Galva, IA).

This process involves pretreatment with cellulosic enzymes, yeast, and heat which utilizes the corn kernel fiber to produce cellulosic wet distillers grains (C-WDG). The first research with C-WDG was recently conducted at ISU to evaluate the feeding value C-WDG compared to traditional wet distillers grains (T-WDG) in finishing cattle diets.

One hundred sixty-eight steers (928 ± 10 lbs) were randomly assigned to one of four dietary treatments (6 steers/pen, 7 pens/treatment). Treatments included a corn-based control with 13% T-WDG (CON) to meet crude protein requirements, 30% T-WDG (TRAD), 30% C-WDG (CEL), and 18% C-WDG and 12% condensed corn distillers solubles (CEL+CCDS) and were fed for 94 days prior to harvest.

 As expected, results from this trial reiterate that wet distillers grains are superior to corn in feeding value and energy content in finishing diets. Cattle fed TRAD had heavier final body weights (FBW) and hot carcass weights (HCW), improved ADG and feed conversion, and larger ribeye areas compared to steers finished on CON.

Between steers fed CEL and CEL+CCDS, feed conversion was similar. However, steers fed CEL+CCDS had decreased dry matter intake (DMI) and ADG and thus, lighter FBW. Decreased performance of cattle fed CEL+CCDS may be explained by the sulfur content of the solubles. More moderate inclusions of CCDS to C-WDG may be feasible without decreasing DMI and hindering ADG as observed. 
 
More importantly, no differences were observed in FBW, HCW, ADG, and REA from steers fed TRAD or CEL. However, steers finished on CEL had decreased feed conversion due to increased DMI compared to steers fed TRAD.
 
In summary, wet distillers grains from a novel, secondary fermentation process to produce cellulosic ethanol from corn kernel fiber resulted in similar performance of steers finished on C-WDG or T-WDG. Therefore, incorporation of wet distillers grains derived from a cellulosic ethanol production process still maintained significant feeding value when replacing corn in feedlot cattle diets.