Effect of sulfur content in wet or dry distillers grains fed at several inclusions on cattle growth performance, ruminal parameters, and hydrogen sulfide.

摘要

Effects of S from wet or dry distillers grains with solubles (DGS) containing 0.82 or 1.16% S on animal growth performance, carcass characteristics, apparent total tract digestibility, and ruminal parameters were evaluated. In Exp. 1, crossbred beef steers (n=120; 345+or-34 kg BW) were individually fed ad libitum using Calan gates. Treatments were applied as a 2x2x3+1 factorial treatment arrangement with factors of DGS type (wet or dry), S content in DGS (0.82 or 1.16% DM basis), and DGS inclusion (20, 30, and 40%, DM basis), as well as a corn control diet (no DGS). In Exp. 2, ruminally cannulated crossbred beef steers (n=6; 381+or-31 kg BW) were assigned to 1 of 5 diets in a 5x6 unbalanced Latin Square design and fed ad libitum through five 14-d periods. A 2x2+1 factorial treatment arrangement was used with the factors of DGS type and S content in DGS (similar to Exp. 1). Inclusion of DGS was 40%, except for a MATCH diet containing wet 1.16% S DGS included at 31.4% (DM basis). Intake of DM decreased linearly (P<0.01) and quadratically (P<0.01) for steers fed wet and dry DGS that was 1.16% S, respectively. In addition, steers fed dry DGS consumed 9% more DM (P<0.01) than those fed wet. Gain decreased linearly (P=0.02) when wet 1.16% S DGS increased in the diet, representing a 12% drop in ADG between the Control and 40% DGS inclusion. A quadratic (P=0.02) improvement in G:F was observed for steers fed wet DGS compared with dry, regardless of S content (P=0.52). Feeding diets with wet 1.16% S DGS linearly decreased (P=0.03) HCW. In Exp. 2, molar proportion of propionate declined (P=0.01) 9% and A:P ratio tended (P=0.13) to be greater when 1.16 compared with 0.82% S DGS was fed. Apparent total tract DMD was not affected (P>0.16) and only subtle changes (P<0.01) in ruminal pH parameters were observed. Greater (P=0.02) ruminal H₂S concentration for steers fed wet compared with dry DGS was observed, while 1.16% S DGS tended (P=0.12) to produce greater ruminal H₂S than 0.82% S. Sulfur in wet DGS appears to be more prone to be converted to ruminal H₂S, because feeding 1.16% S as wet DGS had a greater impact on ADG, DMI, and ruminal H₂S compared with dry DGS.