Limits...
Fine-mapping QTL for mastitis resistance on BTA9 in three Nordic red cattle breeds.

Sahana G, Lund MS, Andersson-Eklund L, Hastings N, Fernandez A, Iso-Touru T, Thomsen B, Viitala S, Sørensen P, Williams JL, Vilkki J - Anim. Genet. (2008)

Bottom Line: This QTL showed a pleiotropic effect on SCS in the DR and SRB breeds.This QTL was also associated with yield traits in DR but not in FA or SRB.No QTL were found for udder conformation traits on chromosome 9.

View Article: PubMed Central - PubMed

Affiliation: Department of Genetics and Biotechnology, Faculty of Agricultural Sciences, Aarhus University, Research Centre Foulum, DK-8830 Tjele, Denmark. goutam.sahana@agrsci.dk

ABSTRACT
A QTL affecting clinical mastitis and/or somatic cell score (SCS) has been reported previously on chromosome 9 from studies in 16 families from the Swedish Red and White (SRB), Finnish Ayrshire (FA) and Danish Red (DR) breeds. In order to refine the QTL location, 67 markers were genotyped over the whole chromosome in the 16 original families and 18 additional half-sib families. This enabled linkage disequilibrium information to be used in the analysis. Data were analysed by an approach that combines information from linkage and linkage disequilibrium, which allowed the QTL affecting clinical mastitis to be mapped to a small interval (<1 cM) between the markers BM4208 and INRA084. This QTL showed a pleiotropic effect on SCS in the DR and SRB breeds. Haplotypes associated with variations in mastitis resistance were identified. The haplotypes were predictive in the general population and can be used in marker-assisted selection. Pleiotropic effects of the mastitis QTL were studied for three milk production traits and eight udder conformation traits. This QTL was also associated with yield traits in DR but not in FA or SRB. No QTL were found for udder conformation traits on chromosome 9.

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QTL profiles (— LA; ♦ LDLA; × LD; 5% significant threshold) for the clinical mastitis showing an LDLA/LD peak between the markers BM4208 and INRA144 in combined analyses of Finnish Ayrshire, Danish Red and Swedish Red and White cattle.
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fig01: QTL profiles (— LA; ♦ LDLA; × LD; 5% significant threshold) for the clinical mastitis showing an LDLA/LD peak between the markers BM4208 and INRA144 in combined analyses of Finnish Ayrshire, Danish Red and Swedish Red and White cattle.

Mentions: All three models, STLA, STLDLA and STLD, detected QTL affecting CM segregating on BTA9 when the combined data from three breeds were analysed (Tables 1–3). These results were in agreement with the analyses within individual breeds, and gave a narrow LDLA/LD peak for CM at 73.9 cM (Tables 1 and 2; Fig. 1). The QTL interval using the STLA model spanned the region from 59 to 81 cM. In this interval, there was more than one peak when LDLA analysis was applied. However, fitting a two-QTL model with one QTL fixed at 73.9 cM and searching for the second QTL did not provide evidence of another linked QTL for CM segregating in this chromosomal region. The highest LRT for the SCS QTL was at 95.1 cM in both the STLA and STLDLA models (Tables 1 and3). The STLDLA model gave an additional peak for SCS at 74.1 cM between markers BM2819 and INRA144, close to the CM QTL location. The QTL explained 18% and 17% of the total genetic variance for CM and SCS respectively.


Fine-mapping QTL for mastitis resistance on BTA9 in three Nordic red cattle breeds.

Sahana G, Lund MS, Andersson-Eklund L, Hastings N, Fernandez A, Iso-Touru T, Thomsen B, Viitala S, Sørensen P, Williams JL, Vilkki J - Anim. Genet. (2008)

QTL profiles (— LA; ♦ LDLA; × LD; 5% significant threshold) for the clinical mastitis showing an LDLA/LD peak between the markers BM4208 and INRA144 in combined analyses of Finnish Ayrshire, Danish Red and Swedish Red and White cattle.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2655356&req=5

fig01: QTL profiles (— LA; ♦ LDLA; × LD; 5% significant threshold) for the clinical mastitis showing an LDLA/LD peak between the markers BM4208 and INRA144 in combined analyses of Finnish Ayrshire, Danish Red and Swedish Red and White cattle.
Mentions: All three models, STLA, STLDLA and STLD, detected QTL affecting CM segregating on BTA9 when the combined data from three breeds were analysed (Tables 1–3). These results were in agreement with the analyses within individual breeds, and gave a narrow LDLA/LD peak for CM at 73.9 cM (Tables 1 and 2; Fig. 1). The QTL interval using the STLA model spanned the region from 59 to 81 cM. In this interval, there was more than one peak when LDLA analysis was applied. However, fitting a two-QTL model with one QTL fixed at 73.9 cM and searching for the second QTL did not provide evidence of another linked QTL for CM segregating in this chromosomal region. The highest LRT for the SCS QTL was at 95.1 cM in both the STLA and STLDLA models (Tables 1 and3). The STLDLA model gave an additional peak for SCS at 74.1 cM between markers BM2819 and INRA144, close to the CM QTL location. The QTL explained 18% and 17% of the total genetic variance for CM and SCS respectively.

Bottom Line: This QTL showed a pleiotropic effect on SCS in the DR and SRB breeds.This QTL was also associated with yield traits in DR but not in FA or SRB.No QTL were found for udder conformation traits on chromosome 9.

View Article: PubMed Central - PubMed

Affiliation: Department of Genetics and Biotechnology, Faculty of Agricultural Sciences, Aarhus University, Research Centre Foulum, DK-8830 Tjele, Denmark. goutam.sahana@agrsci.dk

ABSTRACT
A QTL affecting clinical mastitis and/or somatic cell score (SCS) has been reported previously on chromosome 9 from studies in 16 families from the Swedish Red and White (SRB), Finnish Ayrshire (FA) and Danish Red (DR) breeds. In order to refine the QTL location, 67 markers were genotyped over the whole chromosome in the 16 original families and 18 additional half-sib families. This enabled linkage disequilibrium information to be used in the analysis. Data were analysed by an approach that combines information from linkage and linkage disequilibrium, which allowed the QTL affecting clinical mastitis to be mapped to a small interval (<1 cM) between the markers BM4208 and INRA084. This QTL showed a pleiotropic effect on SCS in the DR and SRB breeds. Haplotypes associated with variations in mastitis resistance were identified. The haplotypes were predictive in the general population and can be used in marker-assisted selection. Pleiotropic effects of the mastitis QTL were studied for three milk production traits and eight udder conformation traits. This QTL was also associated with yield traits in DR but not in FA or SRB. No QTL were found for udder conformation traits on chromosome 9.

Show MeSH
Related in: MedlinePlus