title: Constraints for nutritional grouping in Wisconsin and Michigan dairy farms.
abstract: A survey was conducted in Wisconsin (WI) and Michigan (MI) to quantify the proportion of farms that use a single diet for all lactating cows and to better understand the reasons for current grouping strategies and the limitations to grouping for better nutritional management. A questionnaire was mailed to all WI dairy farmers with ≥200 lactating cows (971 farms) and to a random sample of grade-A MI dairy farmers (800 farms) of varying herd sizes. The survey return rate was 20% in WI (196 farms) and 26% in MI (211 farms; 59 of them had ≥200 lactating cows). Feeding 2 or more different diets to lactating cows was predominant: 63% in WI (124 farms, all ≥200 lactating cows), 76% in MI farms with ≥200 lactating cows (45 farms), and 28% in MI farms with <200 lactating cows (43 farms). Farmers feeding more than 1 diet used 1 or more of the following criteria for grouping lactating cows: stage of lactation, milk production, or body condition score. Overall for both states, 52% of the farms (211 from 407 farms) feeding more than 1 diet grouped cows according to their nutritional needs. However, a notable population of farms fed the same diet to all lactating cows: 37% in WI (72 farms), 24% in MI (14 farms) for herds of ≥200 lactating cows, and 72% in MI for herds of <200 lactating cows (109 MI farms). "Desire to keep it simple" and "milk drops when cows are moved to a different group" were identified as main constraints to having more groups within a farm for nutritional purposes. Farm facilities and labor were also limiting factors to grouping in farms with herd sizes of <200 lactating cows.
authors.affiliation: Department of Dairy Science, University of Wisconsin, Madison 53706.
authors.forename: F E
authors.initials: FE
authors.lastname: Contreras-Govea
authors.affiliation: Department of Dairy Science, University of Wisconsin, Madison 53706. Electronic address: vcabrera@wisc.edu.
authors.forename: V E
authors.initials: VE
authors.lastname: Cabrera
authors.affiliation: Department of Dairy Science, University of Wisconsin, Madison 53706.
authors.forename: L E
authors.initials: LE
authors.lastname: Armentano
authors.affiliation: Department of Dairy Science, University of Wisconsin, Madison 53706.
authors.forename: R D
authors.initials: RD
authors.lastname: Shaver
authors.affiliation: Department of Computing and Biometry, University of Wisconsin, Madison 53706.
authors.forename: P M
authors.initials: PM
authors.lastname: Crump
authors.affiliation: Department of Animal Science, Michigan State University, East Lansing 48824.
authors.forename: D K
authors.initials: DK
authors.lastname: Beede
authors.affiliation: Department of Animal Science, Michigan State University, East Lansing 48824.
authors.forename: M J
authors.initials: MJ
authors.lastname: VandeHaar
mesh_terms: D000383:Agriculture; D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001823:Body Composition; D002417:Cattle / Q000502:physiology*; D003612:Dairying / Q000379:methods*; D004032:Diet / Q000662:veterinary*; D005260:Female; D006799:Housing, Animal; D007774:Lactation; D008824:Michigan; D008892:Milk; D009751:Nutritional Requirements; D011795:Surveys and Questionnaires; D014922:Wisconsin
keywords: diet management; feed efficiency; precision feeding; survey