| The effects of modified-wet distiller's grain with soluble (MDGS) on partitioning of fat between depots was studied in two experiments. Treatments were 0, 20, or 40% MDGS (DMB), replacing high-moisture corn in both experiments. In Exp. 1, crossbred cattle (n = 168) were used in a randomized complete block design (n = 7 pens/treatment). Ultrasound scans were taken every 56 d and cattle were harvested when the average 12th rib fat thickness (SF) was estimated to be 1.02 cm. Feeding MDGS had no effect on DMI and ADG. Dressing percent, G:F, calculated yield grade, and IMR (IMF:SF ratio IMF = intramuscular fat) tended to increase with MDGS. Feeding MDGS resulted in fewer USDA Choice carcasses, but more yield grade 3 and Select. The ultrasound IMR was lower (P < 0.01) in cattle fed MDGS vs. the control. Color, tenderness and proximate analysis of LM were not affected by diet. Within depot, FA composition was altered with MDGS. Exp. 2 evaluated the effects of feeding MDGS on metabolism with ruminally-fistulated steers (n=6) in a 3 x 3 Latin square design. The amount of N and P retained, P excreted, and digestibility of N, P, ADF and NDF increased with MDGS level. Levels of VFA's were similar among treatments with the exception of valeric which increased linearly (P < 0.02) with MDGS. Including MDGS in the diet may affect energy partitioning between IMF and SF. Feeding MDGS tended to improve G:F and increased SF with minimal effects on IMF, and no effect on color and tenderness. |
