Effects of fat level in distillers grain on finishing feedlot performance and carcass traits
The objective of this study was to evaluate the effects of different corn oil levels in distillers grains (DG) on beef cattle performance during finishing and the effects on carcass traits. Angus sired steers (n=182, 461.97 ± 4.38 kg) were blocked by weight (fall calves and yearlings) and allocated to one of four treatments based on corn oil level in DG: 1) control (CON) no DG; 2) low corn oil (LOW, 5.47%); 3) medium corn oil (MED, 8.05%); and 4) high corn oil (HIGH, 12.96%). Eleven or 12 steers were assigned to each of 16 pens with four replicates per treatment. Steers were fed a corn based diet (136 Mcal/kg) to appetite formulated to meet or exceed NRC requirements. Steers were weighed after 28d on feed and at the end of the finishing period which was an additional 41d for the light blocks and 77d for the heavy blocks. Steers were marketed in two drafts at Tyson Fresh Meats, Dakota City, NE with carcass traits evaluated by the same trained grader. Fat level in the ration for the respective treatments was 3.58, 4.02, 4.52, and 5.48, for CON, LOW, MED, and HIGH. DG was included in the finishing diet at 19.4% (DM basis) with sunflower meal (2.44 % oil) used in the CON ration. DMI tended to increase linearly with corn oil during the first 28 d on feed (P < 0.07) with 12.54, 12.78, 13.11 kg/hd/d consumed by LOW, MED, and HIGH, respectively. Feed intake was affected quadratically during the final finishing period (P < 0.03), and over the entire feeding period (P < 0.05). There is some suggestion (P < 0.13) of linearly improving gain with increasing corn oil during the first 28 d on feed, however, overall ADG was not affected by treatment (P > 0.27). Gain efficiency was not affected (P > 0.26) by treatment. Marbling score increased linearly (P < 0.02) with increasing corn oil. Yield Grade tended to increase linearly (P < 0.07) from 2.98 to 3.27 for CON and HIGH, respectively, and REA tended to decrease (P < 0.07) with increasing corn oil but other carcass traits were not affected (P > 0.27). These data indicate that higher corn oil in DG has some positive effect on feed intake and marbling but does not affect gain or gain efficiency.
Keywords: beef, distillers grain, corn oil