title: Invited review: An evaluation of the likely effects of individualized feeding of concentrate supplements to pasture-based dairy cows.
abstract: In pasture-based dairy systems, supplementary feeds are used to increase dry matter intake and milk production. Historically, supplementation involved the provision of the same amount of feed (usually a grain-based concentrate feed) to each cow in the herd during milking (i.e., flat-rate feeding). The increasing availability of computerized feeding and milk monitoring technology in milking parlors, however, has led to increased interest in the potential benefits of feeding individual cows (i.e., individualized or differential feeding) different amounts and types of supplements according to one or more parameters (e.g., breeding value for milk yield, current milk yield, days in milk, body condition score, reproduction status, parity). In this review, we consider the likely benefits of individualized supplementary feeding strategies for pasture-based dairy cows fed supplements in the bail during milking. A unique feature of our review compared with earlier publications is the focus on individualized feeding strategies under practical grazing management. Previous reviews focused primarily on research undertaken in situations where cows were offered ad libitum forage, whereas we consider the likely benefits of individualized supplementary feeding strategies under rotational grazing management, wherein pasture is often restricted to all or part of a herd. The review provides compelling evidence that between-cow differences in response to concentrate supplements support the concept of individualized supplementary feeding.
authors.affiliation: Tasmanian Institute of Agriculture, Dairy Center, The University of Tasmania, Burnie, Tasmania 7320, Australia.
authors.forename: J L
authors.initials: JL
authors.lastname: Hills
authors.affiliation: Agriculture Research Division, Department of Environment and Primary Industries, Ellinbank, Victoria 3821, Australia.
authors.forename: W J
authors.initials: WJ
authors.lastname: Wales
authors.affiliation: Melbourne School of Land and Environment, The University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: F R
authors.initials: FR
authors.lastname: Dunshea
authors.affiliation: MC Franklin Laboratory, Faculty of Veterinary Science, University of Sydney, Camden, New South Wales 2570, Australia.
authors.forename: S C
authors.initials: SC
authors.lastname: Garcia
authors.affiliation: DairyNZ, Private Bag 3221, Hamilton 3240, New Zealand. Electronic address: John.Roche@dairynz.co.nz.
authors.forename: J R
authors.initials: JR
authors.lastname: Roche
mesh_terms: D000818:Animals; D002417:Cattle; D004032:Diet / Q000662:veterinary; D004044:Dietary Proteins / Q000008:administration & dosage; D019587:Dietary Supplements; D002523:Edible Grain; D005260:Female; D007774:Lactation; D008892:Milk / Q000378:metabolism; D006109:Poaceae; D012820:Silage / Q000032:analysis*
chemical_list: D004044:Dietary Proteins
keywords: feed conversion efficiency; grazing; milk response; substitution