title: Short communication: Multi-trait estimation of genetic parameters for milk protein composition in the Danish Holstein.
abstract: Genetic parameters were estimated for the major milk proteins using bivariate and multi-trait models based on genomic relationships between animals. The analyses included, apart from total protein percentage, αS1-casein (CN), αS2-CN, β-CN, κ-CN, α-lactalbumin, and β-lactoglobulin, as well as the posttranslational sub-forms of glycosylated κ-CN and αS1-CN-8P (phosphorylated). Standard errors of the estimates were used to compare the models. In total, 650 Danish Holstein cows across 4 parities and days in milk ranging from 9 to 481d were selected from 21 herds. The multi-trait model generally resulted in lower standard errors of heritability estimates, suggesting that genetic parameters can be estimated with high accuracy using multi-trait analyses with genomic relationships for scarcely recorded traits. The heritability estimates from the multi-trait model ranged from low (0.05 for β-CN) to high (0.78 for κ-CN). Genetic correlations between the milk proteins and the total milk protein percentage were generally low, suggesting the possibility to alter protein composition through selective breeding with little effect on total milk protein percentage.
authors.affiliation: Center for Quantitative Genetics and Genomics, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark; Animal Breeding and Genomics Centre, Wageningen University, PO Box 338, 6700 AH Wageningen, the Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Gebreyesus
authors.affiliation: Center for Quantitative Genetics and Genomics, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
authors.forename: M S
authors.initials: MS
authors.lastname: Lund
authors.affiliation: Center for Quantitative Genetics and Genomics, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
authors.forename: L
authors.initials: L
authors.lastname: Janss
authors.affiliation: Department of Food Science, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
authors.forename: N A
authors.initials: NA
authors.lastname: Poulsen
authors.affiliation: Department of Food Science, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
authors.forename: L B
authors.initials: LB
authors.lastname: Larsen
authors.affiliation: Animal Breeding and Genomics Centre, Wageningen University, PO Box 338, 6700 AH Wageningen, the Netherlands.
authors.forename: H
authors.initials: H
authors.lastname: Bovenhuis
authors.affiliation: Center for Quantitative Genetics and Genomics, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark. Electronic address: bart.buitenhuis@mbg.au.dk.
authors.forename: A J
authors.initials: AJ
authors.lastname: Buitenhuis
mesh_terms: D000818:Animals; D002417:Cattle / Q000235:genetics*; D003718:Denmark; D005260:Female; D008892:Milk / Q000737:chemistry*; D008894:Milk Proteins / Q000737:chemistry* / Q000235:genetics*; D008957:Models, Genetic
chemical_list: D008894:Milk Proteins
keywords: genetic parameter; genomic relationship; milk protein; multi-trait model