Bermudagrass Cultivar and Supplementation Level of DDGS Effects on Stocker Cattle Performance.

Distillers' dried grains with solubles (DDGS) has provided opportunities for supplementation of stocker cattle. The objective of this 2 yr study was to evaluate the interaction of bermudagrass (Cynodon dactylon [L.] Pers.) cultivar (‘Tifton 85’ [TIF] or ‘Coastal’ [COS]) and DDGS supplementation level (SUPP) on performance of steers through a summer stocker phase. Steers (TIF: n = 112, 363 ± 3.7 kg BW; COS: n = 63, 377 ± 4.6 kg BW) were stratified by BW and randomly allocated to pastures (TIF: n = 16, 0.7 ± 0.01 ha; COS: n = 9, 1.3 ± 0.17 ha) each year at 3 levels of SUPP (0, 0.25, or 1% BW hd-1 d-1). Animals grazed for approximately 105 d in each year and were weighed every 21 d. Data were analyzed using SAS PROC MIXED. Steer ADG (kg d^-1) was greatest (P < 0.05) from TIF at 1% (1.3) and least from both TIF at 0% (0.8) and COS at 0 and 0.25% (0.8). The ADG from COS at 1% (1.1) and TIF at 0.25% (1.1) was intermediate. Additional gain (kg d^-1)from SUPP was greatest (P < 0.05) from TIF at 1% (0.7) and least from COS at 0.25% (0.2), with COS at 1% (0.5) and TIF at 0.25% (0.5) as intermediate. Stocking rate (SR; 340 kg = 1 steer) was greater (P < 0.05) from TIF at 16.4 than COS at 9.2 hd ha^-1. Pasture gain (kg ha^-1) was greatest (P < 0.05) from TIF at 1% (1867), followed by TIF at 0.25% (1232) and least from COS both at 0% (508) and 0.25% (609). Pasture gain from COS at 1% (1017) and TIF at 0% (849) was intermediate. Depending on SR and cattle value, SUPP may be a viable option for stocker cattle, and benefit could be greater on TIF.