title: Genome-wide association study for lactation persistency, female fertility, longevity, and lifetime profit index traits in Holstein dairy cattle.
abstract: Female fertility in Holstein cattle can decline when intense genetic selection is placed on milk production. One approach to improving fertility is to identify the genomic regions and variants affecting fertility traits and then incorporate this knowledge into selection decisions. The objectives of this study were to identify or refine the positions of the genomic regions associated with lactation persistency, female fertility traits (age at first service, cow first service to conception, heifer and cow nonreturn rates), longevity traits (herd life, indirect herd life, and direct herd life), and lifetime profit index in the North American Holstein dairy cattle population. A genome-wide association study was performed for each trait, using a single SNP (single nucleotide polymorphism) regression mixed linear model and imputed high-density panel (777k) genotypes. No associations were identified for fertility traits. Several peak regions were detected for lifetime profit index, lactation persistency, and longevity. The results overlap with previous findings and identify some novel regions for lactation persistency. Previously proposed causative and candidate genes supported by this work include DGAT1, GRINA, and CPSF1, whereas new candidate genes are SLC2A4RG and THRB. Thus, the chromosomal regions identified in this study not only confirm several previous findings but also highlight new regions that may contribute to genetic variation in lactation persistency and longevity-associated traits in dairy cattle.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada, T6G 2P5.
authors.forename: S
authors.initials: S
authors.lastname: Nayeri
authors.affiliation: Centre for the Genetic Improvement of Livestock, University of Guelph, Ontario, Canada, N1G 2W1; The Semex Alliance, Guelph, Ontario, Canada, N1H 6J2.
authors.forename: M
authors.initials: M
authors.lastname: Sargolzaei
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada, T6G 2P5; Department of Animal and Poultry Production, Damanhour University, Damanhour, Egypt.
authors.forename: M K
authors.initials: MK
authors.lastname: Abo-Ismail
authors.affiliation: Centre for the Genetic Improvement of Livestock, University of Guelph, Ontario, Canada, N1G 2W1; Angus Genetics Inc., American Angus Association, St. Joseph, MO 64506.
authors.forename: S
authors.initials: S
authors.lastname: Miller
authors.affiliation: Centre for the Genetic Improvement of Livestock, University of Guelph, Ontario, Canada, N1G 2W1.
authors.forename: F
authors.initials: F
authors.lastname: Schenkel
authors.affiliation: Agriculture and Food Innovation, Center for Animal Science, University of Queensland, St Lucia QLD 4072, Australia.
authors.forename: S S
authors.initials: SS
authors.lastname: Moore
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada, T6G 2P5. Electronic address: stothard@ualberta.ca.
authors.forename: P
authors.initials: P
authors.lastname: Stothard
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D005298:Fertility / Q000235:genetics; D055106:Genome-Wide Association Study / Q000662:veterinary*; D007774:Lactation / Q000235:genetics; D008136:Longevity; D010641:Phenotype
keywords: fertility; genome-wide association study; lifetime profit index; longevity