Effects of dry-rolled or high-moisture corn with twenty-five or forty-five percent wet distillers' grains with solubles on energy metabolism, nutrient digestibility, and macromineral balance in finishing beef steers.

The effects of feeding a dry-rolled corn-based diet (DRCB) or a combination of a high-moisture corn-based diet (HMCB) with dry-rolled corn (DRC; 2:1 ratio of high-moisture corn [HMC] and DRC) with 25 and 45% wet distillers' grains with solubles (WDGS) on energy metabolism and nutrient and mineral balance were evaluated in 8 finishing steers using a replicated Latin square design. The model included the fixed effects of dietary treatment, the WDGS × diet type interaction, and period and the random effects of square and steer within square were also included. Treatments consisted of a DRCB with 25% WDGS, a DRCB with 45% WDGS, a combination of HMCB and DRC with 25% WDGS, and a combination of HMCB and DRC with 45% WDGS. Cattle consuming DRCB consumed a greater amount of DM ( < 0.01) and GE intake was also greater when feeding DRCB with 25% WDGS than when feeding DRCB with 45% WDGS ( < 0.01). As a proportion of GE intake, cattle consuming HMCB had a greater fecal energy loss ( = 0.01). Digestible energy loss as a proportion of GE intake was greater when cattle were fed DRCB than when cattle were fed HMCB ( = 0.01) and when WDGS was included at 45% of DM ( = 0.05). As a proportion of GE intake, cattle consuming DRCB and 25% WDGS respired a greater amount of methane (Mcal) than cattle consuming 45% WDGS. As a proportion of GE intake, ME was greater in DRCB than in HMCB ( = 0.01). Within HMCB, 45% WDGS had more megacalories of retained energy than 25% WDGS. Nitrogen excretion (g) was greater in the urine ( < 0.01) and feces ( < 0.05) when 45% WDGS was included. As a proportion of N intake, total N retained was greater when a greater amount of WDGS was included in the diet ( = 0.05). Digestibility was greater in DRCB than in HMCB ( = 0.02). Starch intake, excretion, and digestibility as a proportion of intake were greater in DRCB than in HMCB ( < 0.01) and when WDGS was included at 25% than when WDGS was included at 45% of the diet ( < 0.01). Intake of ether extract was greater in HMCB when 45% WDGS was included ( < 0.01), and fecal excretion was greater in diets including 25% WDGS than in diets including 45% WDGS ( = 0.02). Sulfur intake was greater as the inclusion of WDGS increased from 25 to 45% ( < 0.01). We interpret that if the basal concentrate portion of the diet is based on HMC, adding an increased amount of WDGS can improve retained energy, and within DRCB, more energy is retained as fat and carbohydrate when cattle were fed 25% WDGS.

Nutrient excretion and odorant production in manure from cattle fed corn wet distillers grains with solubles.

Twenty-four cross bred steers (BW 452.5 +/- 15.5 kg) were used to evaluate nutrient excretion and odorous compounds in urine and feces of feedlot steers fed diets containing corn wet distillers grains with solubles (WDGS). Cattle were weighed, blocked by BW, and assigned randomly to 1 of 4 dry-rolled corn-based diets containing 0, 20, 40, or 60% WDGS (DM basis). A 96-h total fecal and urine collection was conducted. Orts, feces, and urine were collected daily. Samples were analyzed for moisture, total N, total P, water soluble P, and total S. Fresh fecal samples were collected at the end of the balance trial for analysis of VFA, phenol, p-cresol, indole, skatole, ammonia-N, and lactate concentration. Total P, N, and S intake increased linearly as the amount of WDGS increased in the diet (P or= 0.11). Total N excretion increased linearly as dietary WDGS inclusion increased (P < 0.01) and was due to a linear increase in urinary N excretion (P < 0.01). Total S excretion also increased as WDGS concentration increased in the diet (P < 0.01). Dietary treatment did not affect the concentration of odorous compounds in urine (P >or= 0.07). Total VFA concentration in feces decreased as WDGS increased in the diet (P < 0.01), but branched-chained VFA concentrations (isobutyrate and isovalerate) and phenol in feces increased when WDGS replaced corn in the diet (P or= 0.09). This study indicates that feedlot cattle fed increasing amounts of WDGS had increased P, N, and S intake and excretion, which may contribute to the production of odorous compounds (primarily long- and branched-chain VFA, and phenol) as well as increased ammonia and H(2)S emissions from the feedlot. Increased P concentration in livestock waste will increase the amount of land necessary to utilize manure P. Because of increased urinary P excretion, producers should consider environmental implications of liquid runoff from the feedlot surface as well as solid manure when WDGS are fed to feedlot cattle.

Odorant production and persistence of Escherichia coli in manure slurries from cattle fed zero, twenty, forty, or sixty percent wet distillers grains with solubles.

Corn ethanol production removes starch and concentrates the remaining nutrients, including CP and minerals. When wet distillers grains with solubles (WDGS) are fed to cattle in place of corn, CP and minerals often exceed dietary needs. This may increase N emission, P run-off, and odor production. These variables are evaluated in this study. Crossbred steers (n = 160; 434 +/- 8 kg) were assigned in a completely randomized block design to 9 x 9 m pens with concrete floor (10 animals/pen; 4 pens/treatment). Steers were fed a finishing diet that contained 0, 20, 40, or 60% WDGS on a DM basis, and provided 13.3, 15.5, 20.6, or 24.9% CP, respectively. Two kilograms of manure slurry (14 to 23% DM) were collected from each pen monthly (Aug. 20, Sep. 24, and Oct. 22). Samples were analyzed immediately for odorants, DM, pH, NH(3), total alcohol, l-lactate, and concentrations of generic Escherichia coli. After incubation of the samples at 22 degrees C for 2, 4, 7, 10, 15, 21, and 28 d, samples were analyzed for methane production in addition to the above characteristics. Before incubation, NH(3), H(2)S, indole, phenol, isovalerate, isobutyrate, and acetate increased (P < 0.01) with increasing amounts of WDGS in the diet. Other odorants, including skatole, caproate, valerate, butyrate, and propionate, were greater (P < 0.01) in manure slurries from cattle fed 20 or 40% WDGS, compared to 0% WDGS. The l-lactate was greater (P < 0.01) in slurries from cattle fed 0% WDGS (447 mu mol/g of DM) compared with the other treatment slurries (14 to 15 mu mol/g of DM). After incubation, l-lactate contributed to lowered slurry pH (6.3, 7.1, 7.6, and 8.2, respectively, for 0, 20, 40, and 60% WDGS), which inhibited microbial fermentation, E. coli persistence, and methane production. Because of the favorable, more neutral pH in the 40 and 60% WDGS slurries, many of the odorant compounds were rapidly converted to methane during a 28-d static incubation. Escherichia coli O157:H7 inoculated into subsamples of the manure slurries exhibited behavior similar to that of naturally present generic E. coli, surviving in greater numbers longer (P < 0.05) in 20 and 40% WDGS slurries than in 0% WDGS. These data indicate feeding WDGS can increase odorants in manure slurries and extend the persistence of E. coli.

Nutrient database for distiller's dried grains with solubles produced from new ethanol plants in Minnesota and South Dakota.

A study was conducted to evaluate the nutrient content and variability of distiller's dried grains with solubles (DDGS) originating from new (less than 5 yr old) ethanol plants in Minnesota and South Dakota. Ten plants (8 MN, 2 SD) participated in the study, submitting a total of 118 samples. Samples were collected every 2 mo from ten ethanol plants in the Minnesota-South Dakota (MNSD) region from 1997 to 1999 and were analyzed for amino acid levels, DM, CP, crude fiber, crude fat, ash, ADF, NDF, Ca, P, K, Mg, S, Na, Zn, Mn, Cu, and Fe analysis. Digestible energy (DE), ME, and NFE levels were also calculated. Means (dry-matter basis) and coefficients of variation for each nutrient among all plants during 1997 to 1999 were DM (88.9%, 1.7%), CP (30.2%, 6.4%), crude fat (10.9%, 7.8%), crude fiber (8.8%, 8.7%), ash (5.8%, 14.7%), NFE (45.5%, 6.1%), ADF (16.2%, 28.4%), NDF (42.1%, 14.3%), calculated DE (3,990 kcal/kg, 3.24%), calculated ME (3,749 kcal/kg, 3.28%), Arg (1.20%, 9.1%), His (0.76%, 7.8%), Ile (1.12%, 8.7%), Leu (3.55%, 6.4%), Lys (0.85%, 17.3%), Met (0.55%, 13.6%), Phe (1.47%, 6.6%), Thr (1.13%, 6.4%), Trp (0.25%, 6.7%), Val (1.50%, 7.2%), Ca (0.06%, 57.2%), and P (0.89%, 11.7%), respectively. Among the amino acids analyzed, Lys was the most variable (CV = 17.3%), followed by Met (CV = 13.6%). Nutrient levels of MNSD DDGS were higher in crude fat, NDF, DE, ME, P, Lys, Met, and Thr and lower for DM, ADF, and Ca than NRC (1998) values. Nutrient values differed between years for ash, DE, Mn, Zn, Cys (P < 0.10), Fat, TDN, ME, Met, Ile (P < 0.05), Ca, P, K, Mg, and Cu (P < 0.01). These results suggest that gross energy; P; and total Lys, Met, and Thr levels are higher in DDGS from MNSD ethanol plants compared to published values and chemical analysis values of a DDGS sample obtained from an older Midwestern plant.