Feeding of DDGS in lamb rations

Little scientific documentation is available that evaluates maximum levels of dried distiller grain with solubles (DDGS) in lamb-finishing rations. The objective of this research was to evaluate the effect of feeding increasing levels of DDGS in lamb-finishing rations on lamb performance and carcass characteristics. Two-hundred forty Western, white-faced Rambouillet wether and ewe lambs (31.7 ± 0.6 kg BW) were stratified by weight and sex, randomly allotted to one of 16 pens, and assigned to treatment (n = 4). Diets were balanced to meet CP, energy, and Cu requirements; however, treatments were not formulated to be isocaloric or isonitrogenous. The basal diet consisted of alfalfa hay, soybean meal, barley, and a trace mineral supplement. Dried distillers grains with solubles replaced barley and soybean meal at 0 percent, 20 percent, 40 percent, and 60 percent of the diet, respectively (DM basis). Sulfur concentrations of diets were 0.22 percent, 0.32 percent, 0.47 percent, and 0.55 percent for the 0 percent , 20 percent , 40 percent , and 60 percent diets, respectively. Thiamin was included at 142 mg·hd-1·d-1 (DM basis) in all rations for the prevention of polioencephalomalacia. Rations were mixed, ground, and provided ad-libitum. Lambs were weighed on day 0, 32, 56, 83, and 111. Lambs were harvested after the 111 d feeding trial and carcass data collected. Performance and carcass data were analyzed as a completely randomized design. The model included the fixed effect of DDGS treatment and the random effect of pen nested in treatment. Contrast statements included 1) 0 percent vs DDGS inclusion; 2) linear effect of DDGS inclusion; and 3) quadratic effect of DDGS inclusion. Final weight, ADG, G:F, mortality, hotcarcass weight, leg score, carcass conformation score, fat depth, body wall thickness, ribeye area, quality and yield grade, and boneless closely trimmed retail cuts were not affected by treatment (P ≥ 0.15). Feed intake increased in a linear manner (P < 0.001) as level of DDGS inclusion increased. Additionally, flank streaking increased quadratically (P = 0.09) as level of DDGS inclusion increased. Dried distillers grains with solubles maintained lamb performance and had no negative effect on lamb carcass traits. Maximizing the use of DDGS may become economically feasible for lamb feeders when prices become favorable compared to conventional dietary ingredients; however, the level of use of supplemental thiamin for the prevention of potential S-induced polioencephalomalacia in lambs needs to be further evaluated.