Park, A.F.Sheffel, M.V.Titgemeyer, Evan C.Shirley, John E.2011-05-042011-05-042011-05-04http://hdl.handle.net/2097/8592Twenty-four Holstein cows were used in six 4×4 Latin squares to evaluate the effects of substituting extruded-expelled cottonseed meal (Express™) for whole cottonseed and solvent soybean meal in diets for lactating cows. No differences were observed in milk and milk component yield among treatments. Percentages of fat, protein, solids-not-fat, and lactose in milk were similar among treatments. Replacing whole cottonseed with Express™ tended to reduce milk urea nitrogen but had no effect on milk protein percentage or yield. Cow acceptability of Express™ was excellent throughout the 84-day study conducted between late June and September when ambient temperature exceeded 100EF for 35 days. Long-term storage of Express™ in a commodity barn was not a problem. In vitro analysis of Express™ revealed that it contains approximately 75% rumen undegradable protein (RUP) with an intestinally absorbable dietary protein value of 53.4%. Express™ is an excellent source of RUP, and the protein fraction is highly digestible in the small intestine.Lactating cowsExtruder-expelled cottenseed mealConference paper