Effects of sorghum distiller's grains on performance and carcass characteristics of cattle fed steam flaked corn based diets

Two hundred crossbred beef steers (initial body weight = 404.5 ± 16.7 kg) were used to determine the effects of graded levels of wet sorghum distiller's grain and one level of wet com distiller's grain included in steam-flaked corn-based diets of finishing beef steers on performance and carcass characteristics. The five dietary treatments (dry matter basis) included: 1) a standard finishing diet (CON); 2) a diet containing 5% wet sorghum distiller's grain replacing steam-flaked com (5%); 3) a diet with 10% wet sorghum distiller's grain (10%); 4) a diet containing 15% wet sorghum distiller's grain (15%); and 5) a diet with 10% wet corn distiller's grain (C10%) replacing steam-flaked com. Cattle were on feed for an average of 133 d. A randomized complete block design was used with pen as the experimental unit (eight pens per treatment). There was a tendency for a linear decrease in dry matter intake (DMI; P = 0.15) for the overall feeding period as the level of sorghum distiller's grain increased in the diet. In addition, cattle fed the C10% diet tended to consume less DM than those fed the 15% {P = 0.10). A linear decrease in overall average daily gain (ADG; P = 0.01) was noted for cattle fed increasing quantities of sorghum distiller's grain, and this effect was more evident when ADG was adjusted to a common dressing percent (carcass-adjusted ADG; P = 0.001). Feed efficiency, expressed as feed:gain ratio (F:G) followed the same trend (P = 0.12) as overall ADG, as did the carcass-adjusted F:G (P = 0.001). Hot carcass weight and longissimus muscle area decreased linearly (P = 0.009) as the concentration of sorghum distiller's grain increased in the diet. Yield grade increased linearly (P = 0.09) with increasing sorghum distiller's grain level. Steers fed the C10% treatment decreased fat thickness at the 12'*^ rib interface, and kidney, pelvic, and heart fat (P < 0.04) than with the 10% sorghum distillers grain diet. There were no effects on dressing percent, marbling, number of carcasses grading Choice, or the number of liver abscess (P > 0.26). Because of conflicting data from previous research conducted primarily with dry-rolled com-based diets, further research is needed to confirm the lack of response noted in the present study from the replacement of steam-flaked com with wet distiller's grains in the diets of finishing beef cattle.