Using wet distillers grains placed on the ground as a late-season protein supplement for grazing stocker steers and subsequent effects on finishing performance and carcass characteristics

Objective Stocker cattle gains on western Great Plains rangelands are characterized by lower gains during late summer compared with early summer, and thus may also limit rancher use of stocker cattle to diversify livestock classes as a drought mitigation strategy. Our objective was to measure and compare late-summer stocker cattle gains after feeding a protein supplement (on the ground or in a bunk) to a nonsupplemented control. Materials and Methods Eighty steers (initial BW ± SD = 267 ± 22 kg/head) were stocked on 8 pastures (10 steers/pasture) each year from May to October for 4 yr. Two replications of 4 treatments, including (1) wet distillers grains fed in a bunk, (2) wet distillers grains fed on the ground on standing vegetation, (3) a 1:1 mixture of milo: soybean meal fed in a bunk, and (4) a control treatment of no supplement, were compared during a late-summer stocker steer grazing trial. Supplements were fed 3 times per week to supply CP at 0.14 kg/d per steer during the last half (77 d) of the growing season, mid-July to early October. Steers were weighed in May, mid-July, and October on pasture, and at the end of a feedlot finishing phase. Results and Discussion During the last half of the grazing season in 2011 to 2014, animal daily gains were greater for supplemented groups compared with the nonsupplemented control group (0.77 to 0.81 kg/head per day vs. 0.70 kg/head per day, supplemented vs. nonsupplemented, respectively). Gains on pasture from supplemented groups, including the wet distillers group fed on the ground, were not different from each other. Animals not supplemented on pasture had similar gain during the finishing phase in the feedlot compared with animals supplemented on pasture (235.9 kg/head vs. 229.7 kg/head). Implications and Applications Late-season protein supplementation with wet distillers grains, even in small quantities, would benefit stocker cattle gain during most years in this region, whether the supplement is placed on the ground or in a bunk. Any residual amount of distillers supplement that may be remaining on the soil appears to be inconsequential to animal gain. Lack of protein supplement limits stocker animal gains during the late grazing season in western Great Plains rangelands.