Effect of fat source on duodenal flow of trans-C18:1 fatty acids and milk fat production in dairy cows

摘要: Abstract The objective of the study was to determine effects dietary fat source on duodenal flow, apparent absorption, and milk incorporation trans -C 18:1 fatty acids. Four ruminally duodenally cannulated multiparous Holsteins cows in mid late lactation were fed a basal diet containing 36% corn silage, 24% alfalfa haylage, 40% concentrate (dry matter basis). Diets contained 0% supplemental (control diet), 3.7% high oleic sunflower oil, linoleic or partially hydrogenated vegetable shortening; treatments administered 4×4 Latin square design with 3-wk experimental periods. flow duodenum higher for diets supplemented than control (283 vs. 64 g/d). Incomplete biohydrogenation accounted increased oil. Increased shortening most likely originated from diet. Milk percentages 3.48, 3.07, 3.18, 3.38% shortening, respectively. 2.9 11.2% total acids fat, equal across all fat. Ruminal tract digestion organic matter, neutral detergent fiber, N did not change supplementation. Results showed that is reduced fat; however, excessive amounts do necessarily correspond directly depression.