title: Invited review: Opportunities for genetic improvement of metabolic diseases.
abstract: Metabolic disorders are disturbances to one or more of the metabolic processes in dairy cattle. Dysfunction of any of these processes is associated with the manifestation of metabolic diseases or disorders. In this review, data recording, incidences, genetic parameters, predictors, and status of genetic evaluations were examined for (1) ketosis, (2) displaced abomasum, (3) milk fever, and (4) tetany, as these are the most prevalent metabolic diseases where published genetic parameters are available. The reported incidences of clinical cases of metabolic disorders are generally low (less than 10% of cows are recorded as having a metabolic disease per herd per year or parity/lactation). Heritability estimates are also low and are typically less than 5%. Genetic correlations between metabolic traits are mainly positive, indicating that selection to improve one of these diseases is likely to have a positive effect on the others. Furthermore, there may also be opportunities to select for general disease resistance in terms of metabolic stability. Although there is inconsistency in published genetic correlation estimates between milk yield and metabolic traits, selection for milk yield may be expected to lead to a deterioration in metabolic disorders. Under-recording and difficulty in diagnosing subclinical cases are among the reasons why interest is growing in using easily measurable predictors of metabolic diseases, either recorded on-farm by using sensors and milk tests or off-farm using data collected from routine milk recording. Some countries have already initiated genetic evaluations of metabolic disease traits and currently most of these use clinical observations of disease. However, there are opportunities to use clinical diseases in addition to predictor traits and genomic information to strengthen genetic evaluations for metabolic health in the future.
authors.affiliation: Department of Economic Developments, Jobs, Transport and Resources and La Trobe University, Agribio, 5 Ring Road, Bundoora, VIC 3083, Australia. Electronic address: jennie.pryce@ecodev.vic.gov.au.
authors.forename: J E
authors.initials: JE
authors.lastname: Pryce
authors.affiliation: Department of Animal Sciences, University of Florida, Gainesville 32611.
authors.forename: K L
authors.initials: KL
authors.lastname: Parker Gaddis
authors.affiliation: Centre for Genetic Improvement of Livestock, University of Guelph, Guelph, ON, N1G 2W1, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Koeck
authors.affiliation: Agriculture, Bio-engineering and Chemistry Department, Gembloux Agro-Bio Tech, University of Liège, B-5030 Gembloux, Belgium.
authors.forename: C
authors.initials: C
authors.lastname: Bastin
authors.affiliation: Holstein Australia, 24-36 Camberwell Road, Hawthorn East, Victoria, 3122, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Abdelsayed
authors.affiliation: Agriculture, Bio-engineering and Chemistry Department, Gembloux Agro-Bio Tech, University of Liège, B-5030 Gembloux, Belgium.
authors.forename: N
authors.initials: N
authors.lastname: Gengler
authors.affiliation: Centre for Genetic Improvement of Livestock, University of Guelph, Guelph, ON, N1G 2W1, Canada; Canadian Dairy Network, Guelph, ON, N1K 1E5, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Miglior
authors.affiliation: Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, PO Box 5003, NO-1432 Ås, Norway.
authors.forename: B
authors.initials: B
authors.lastname: Heringstad
authors.affiliation: ZuchtData EDV-Dienstleistungen GmbH, Dresdner Str. 89/19, A-1200 Vienna, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Egger-Danner
authors.affiliation: Vereinigte Informationssysteme Tierhaltung w.V. (vit), Heinrich-Schroeder-Weg 1, D-27283 Verden, Germany.
authors.forename: K F
authors.initials: KF
authors.lastname: Stock
authors.affiliation: University of Nottingham, School of Veterinary Medicine and Science, Sutton Bonington Campus, Sutton Bonington, Leicestershire, LE12 5RD, United Kingdom, and; Quality Milk Management Services Ltd., Cedar Barn, Easton Hill, Easton, Wells, Somerset, BA5 1EY, United Kingdom.
authors.forename: A J
authors.initials: AJ
authors.lastname: Bradley
authors.affiliation: Animal Genomics and Improvement Laboratory, Agricultural Research Service, USDA, Beltsville, MD 20705.
authors.forename: J B
authors.initials: JB
authors.lastname: Cole
mesh_terms: D000818:Animals; D001947:Breeding; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000235:genetics*; D005260:Female; D015994:Incidence; D007662:Ketosis / Q000453:epidemiology / Q000235:genetics / Q000662:veterinary; D007774:Lactation; D008659:Metabolic Diseases / Q000453:epidemiology / Q000235:genetics / Q000662:veterinary*; D008892:Milk / Q000378:metabolism; D010298:Parity; D010319:Parturient Paresis / Q000453:epidemiology* / Q000235:genetics; D011247:Pregnancy
keywords: displaced abomasum; ketosis; metabolic disease; milk fever