| dc.description.abstract | Supplemental fat is predominantly fed in feedlots to increase the energy value of the ration. Feedlots utilize supplemental fat to replace energy from grains because of its lower cost per unit of DE. Our objective was to compare the effects of four supplemental fats (animal fat, VOP, interphase and phos) on digestion and biohydrogenation of the ration, the fatty acid profile reaching the duodenum, and on the profile of absorbed fatty acids. Four ruminally and duodenally cannulated Angus steers were used in a 4 × 4 Latin square. Diet was fed ad libitum at 0700 each day. Periods were 12 d with d1 through 7 for adaptation to the diet, d 8 through 11 was for determination of intake and digestion, and d 12 determined ruminal fermentation. Acid detergent insoluble ash was used as an external marker for duodenal and fecal output determination. Intake of all nutrients did not differ (P ≥ 0.08) between treatments. Ruminal digestion of OM and NDF were greater in IP than AF and VOP (P ≤ 0.05). Ether extract digestion appeared to have occurred in the rumen suggesting marker recovery problems at the duodenum, as digestion of EE is not expected. Total tract fatty acid digestion was similar between all treatments (P ≥ 0.16), and biohydrogenation in the rumen did not differ between treatments (P ≥ 0.05). | en |
