title: Reciprocal combinations of barley and corn grains in oil-supplemented diets: feeding behavior and milk yield of lactating cows.
abstract: The effect of barley-based (BBD) or corn-based diets (CBD), or their equal blend (BCBD) on dry matter (DM) intake, feeding and chewing behavior, and production performance of lactating dairy cows was evaluated. Nine multiparous Holstein cows (75.6 ± 11.0 d in milk) were used in a triplicate 3 × 3 Latin square design with 21-d periods. Forage-to-concentrate ratio (40:60), forage neutral detergent fiber (20% of DM), total neutral detergent fiber (>29% of DM), and geometric mean particle size (4.3mm) were similar among treatments. Meal patterns, including meal size and intermeal interval, were not affected by the dietary treatments and DM intake (25.6 kg/d) was not different among treatments. Ether extract intake increased linearly with increasing amount of the corn grain in the diets. Due to similar feed intake, actual milk (48.6 kg/d), 4% fat-corrected milk (36.8 kg/d), and fat- and protein-corrected milk (38.1 kg/d) yields were not affected by treatments. Average milk protein percentage and yield were 2.83% and 1.37 kg/d, respectively, and were not different across treatments. Milk fat percentage increased linearly with increasing amount of corn grain in the diets and was greater in CBD relative to BCBD but not BBD (2.31, 2.28, and 2.57%, for BBD, BCBD, and CBD, respectively). However, milk fat yield tended to show a linear increase as the amount of corn grain included in the diets increased. Results indicated that changing diet fermentability by replacing barley grain for corn grain in oil-supplemented diets did not influence feeding patterns and thereby no changes in feed intake and milk yield occurred.
authors.affiliation: Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran. Electronic address: kargar@ag.iut.ac.ir.
authors.forename: S
authors.initials: S
authors.lastname: Kargar
authors.affiliation: Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran.
authors.forename: G R
authors.initials: GR
authors.lastname: Ghorbani
authors.affiliation: Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Khorvash
authors.affiliation: Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran.
authors.forename: A
authors.initials: A
authors.lastname: Sadeghi-Sefidmazgi
authors.affiliation: Dairy Science Department, South Dakota State University, Brookings 57007-0647.
authors.forename: D J
authors.initials: DJ
authors.lastname: Schingoethe
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D002417:Cattle / Q000502:physiology*; D004032:Diet / Q000662:veterinary*; D004042:Dietary Fats, Unsaturated / Q000378:metabolism*; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D001467:Hordeum / Q000737:chemistry*; D007774:Lactation / Q000502:physiology*; D008892:Milk / Q000378:metabolism; D003313:Zea mays / Q000737:chemistry*
chemical_list: D004042:Dietary Fats, Unsaturated
keywords: barley and corn grain; dairy cow; feeding and chewing behavior