Effects of strategic supplementation of distillers grains on gains and economic return of yearling cattle grazing cool-season pastures in the summer

Abstract

Objectives: The objective of this experiment was to determine the effects of strategic supplementation on year- ling performance and effects on economic return. Materials and Methods: Predominantly Red Angus- crossbred steers and heifers (12–14 mo old; initial BW = 316 kg, SD = 8.6 kg) grazed crested wheatgrass at 4.3 ha/ yearling for an average of 112 d in a 3-yr study. Treatments were (1) dried distillers grains (DDGS) supplemented at 1.59 kg/yearling per day fed 6 d/wk throughout the entire grazing season (full season, FS), (2) 1.59 kg/ yearling per day supplemented for 6 d/wk only during the latter part of the grazing season (late season, LS), or (3) no supplement (control, CONT). Economic data from 2012 to 2021 were applied to experimental data to create potential yearling marketing scenarios and a partial budget analysis. Costs of both DDGS and live cattle were included. Pasture was the experimental unit (4 replicates in yr 1 and 2; 3 replicates in yr 3) in a randomized complete block design. Results and Discussion: There were no significant year × treatment interactions (P > 0.53) for performance. Supplement increased (P < 0.01) ADG 0.23 kg/d over CONT. Ending BW and ADG did not differ (P = 0.31) between FS and LS. There was a tendency for a treatment × year interaction (P = 0.08) for return to management. A significant increase (P < 0.01) in return to management over CONT was observed in yr 2 for FS and yr 2 and 3 for LS. Overall, FS returned $14.96 more and LS returned $32.21 more per yearling than CONT. Return from LS and FS was greater (P ≤ 0.05) than CONT in all years except 2012, 2019, and 2021. Implications and Applications: Strategically timed supplementation with DDGS as forage quality declined resulted in similar yearling performance as supplementing through the entire grazing season and increased economic return to management.