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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Related in: MedlinePlus

QTL profiles (— LA; ♦ LDLA; × LD;  5% significant threshold) for the clinical mastitis showing an LDLA/LD peak in combined Finnish Ayrshire and Swedish Red and White cattle.
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fig03: QTL profiles (— LA; ♦ LDLA; × LD; 5% significant threshold) for the clinical mastitis showing an LDLA/LD peak in combined Finnish Ayrshire and Swedish Red and White cattle.

Mentions: The STLDLA LRT peaks for CM QTL in DR and FA were only 0.2 cM apart in the within-breed analyses. Therefore, combined analyses of these two breeds were carried out (Fig. 2). The STLDLA analyses identified a QTL for CM at 74.1 cM (Table 1). When STLDLA analysis for CM with four-marker haplotypes was used to calculate the IBD probabilities, the highest LRT was at the same position as observed with the 10-marker haplotype analysis. The combined data from FA and SRB were also jointly analysed, because these two breeds are closely related (Holmberg & Andersson-Eklund 2004). In the STLA analysis, the QTL interval (one-LOD support) for CM was between 64 and 81 cM with the peak LRT at 68.2 cM (Table 3; Fig. 3). The STLDLA profile for CM had three peaks, the highest at 77.2 cM. However, evidence of LD was only around 73.9 cM. Single-trait analysis of SCS with STLA and STLDLA in combined FA and SRB had the highest LRT at 95.1 cM (Tables 1 and 3). Although the LRT for both the STLA and STLDLA models for SCS were significant, no LD was observed at this position.


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 in combined Finnish Ayrshire and Swedish Red and White cattle.
© Copyright Policy
Related In: Results  -  Collection

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

fig03: QTL profiles (— LA; ♦ LDLA; × LD; 5% significant threshold) for the clinical mastitis showing an LDLA/LD peak in combined Finnish Ayrshire and Swedish Red and White cattle.
Mentions: The STLDLA LRT peaks for CM QTL in DR and FA were only 0.2 cM apart in the within-breed analyses. Therefore, combined analyses of these two breeds were carried out (Fig. 2). The STLDLA analyses identified a QTL for CM at 74.1 cM (Table 1). When STLDLA analysis for CM with four-marker haplotypes was used to calculate the IBD probabilities, the highest LRT was at the same position as observed with the 10-marker haplotype analysis. The combined data from FA and SRB were also jointly analysed, because these two breeds are closely related (Holmberg & Andersson-Eklund 2004). In the STLA analysis, the QTL interval (one-LOD support) for CM was between 64 and 81 cM with the peak LRT at 68.2 cM (Table 3; Fig. 3). The STLDLA profile for CM had three peaks, the highest at 77.2 cM. However, evidence of LD was only around 73.9 cM. Single-trait analysis of SCS with STLA and STLDLA in combined FA and SRB had the highest LRT at 95.1 cM (Tables 1 and 3). Although the LRT for both the STLA and STLDLA models for SCS were significant, no LD was observed at this position.

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