My NCBISign In

Display Settings:

Format

Send to:

Choose Destination

    Genet Sel Evol. 2009 Oct 22;41:45.

    Mapping quantitative trait loci (QTL) in sheep. II. Meta-assembly and identification of novel QTL for milk production traits in sheep.

    Raadsma HW, Jonas E, McGill D, Hobbs M, Lam MK, Thomson PC.

    ReproGen - Animal Bioscience Group, Faculty of Veterinary Science, University of Sydney, Camden NSW 2570, Australia. raadsma@camden.usyd.edu.au

    ABSTRACT: An (Awassi x Merino) x Merino backcross family of 172 ewes was used to map quantitative trait loci (QTL) for different milk production traits on a framework map of 200 loci across all autosomes. From five previously proposed mathematical models describing lactation curves, the Wood model was considered the most appropriate due to its simplicity and its ability to determine ovine lactation curve characteristics. Derived milk traits for milk, fat, protein and lactose yield, as well as percentage composition and somatic cell score were used for single and two-QTL approaches using maximum likelihood estimation and regression analysis. A total of 15 significant (P < 0.01) and additional 25 suggestive (P < 0.05) QTL were detected across both single QTL methods and all traits. In preparation of a meta-analysis, all QTL results were compared with a meta-assembly of QTL for milk production traits in dairy ewes from various public domain sources and can be found on the ReproGen ovine gbrowser http://crcidp.vetsci.usyd.edu.au/cgi-bin/gbrowse/oaries_genome/. Many of the QTL for milk production traits have been reported on chromosomes 1, 3, 6, 16 and 20. Those on chromosomes 3 and 20 are in strong agreement with the results reported here. In addition, novel QTL were found on chromosomes 7, 8, 9, 14, 22 and 24. In a cross-species comparison, we extended the meta-assembly by comparing QTL regions of sheep and cattle, which provided strong evidence for synteny conservation of QTL regions for milk, fat, protein and somatic cell score data between cattle and sheep.

    PMID: 19849860 [PubMed - indexed for MEDLINE]

    PMCID: PMC2772855

    Supplemental Content

    Click here to read
    Write to the Help Desk