title: Feeding of by-products completely replaced cereals and pulses in dairy cows and enhanced edible feed conversion ratio.
abstract: When fed human-edible feeds, such as grains and pulses, dairy cows are very inefficient in transforming them into animal products. Therefore, strategies to reduce human-edible inputs in dairy cow feeding are needed to improve food efficiency. The aim of this feeding trial was to analyze the effect of the full substitution of a common concentrate mixture with a by-product concentrate mixture on milk production, feed intake, blood values, and the edible feed conversion ratio (eFCR), defined as human-edible output per human edible input. The experiment was conducted as a change-over design, with each experimental period lasting for 7wk. Thirteen multiparous and 5 primiparous Holstein cows were randomly assigned to 1 of 2 treatments. Treatments consisted of a grass silage-based forage diet supplemented with either conventional ingredients or solely by-products from the food processing industry (BP). The BP mixture had higher contents of fiber and ether extract, whereas starch content was reduced compared with the conventional mixture. Milk yield and milk solids were not affected by treatment. The eFCR in the BP group were about 4 and 2.7 times higher for energy and protein, respectively. Blood values did not indicate negative effects on cows' metabolic health status. Results of this feeding trial suggest that by-products could replace common concentrate supplements in dairy cow feeding, resulting in an increased eFCR for energy and protein which emphasizes the unique role of dairy cows as net food producers.
authors.affiliation: Department of Sustainable Agricultural Systems, Division of Livestock Sciences, BOKU-University of Natural Resources and Life Sciences, 1180 Vienna, Austria. Electronic address: paul.ertl@boku.ac.at.
authors.forename: P
authors.initials: P
authors.lastname: Ertl
authors.affiliation: Department for Farm Animals and Veterinary Public Health, Institute of Animal Nutrition and Functional Plant Compounds, University of Veterinary Medicine, 1210 Vienna, Austria.
authors.forename: Q
authors.initials: Q
authors.lastname: Zebeli
authors.affiliation: Department of Sustainable Agricultural Systems, Division of Livestock Sciences, BOKU-University of Natural Resources and Life Sciences, 1180 Vienna, Austria.
authors.forename: W
authors.initials: W
authors.lastname: Zollitsch
authors.affiliation: Department of Sustainable Agricultural Systems, Division of Livestock Sciences, BOKU-University of Natural Resources and Life Sciences, 1180 Vienna, Austria.
authors.forename: W
authors.initials: W
authors.lastname: Knaus
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle / Q000502:physiology*; D004032:Diet / Q000662:veterinary; D004043:Dietary Fiber; D004044:Dietary Proteins / Q000378:metabolism; D004435:Eating / Q000502:physiology; D002523:Edible Grain; D004734:Energy Metabolism; D005260:Female; D005525:Food-Processing Industry; D006801:Humans; D007220:Industrial Waste; D007774:Lactation / Q000502:physiology; D008892:Milk / Q000737:chemistry; D006109:Poaceae; D011674:Pulse; D012820:Silage; D013213:Starch
chemical_list: D004043:Dietary Fiber; D004044:Dietary Proteins; D007220:Industrial Waste; D013213:Starch
keywords: by-product; dairy cow; efficiency; feed conversion; organic