Estimate of heritability and genetic trend of intervertebral disc calcification in Dachshunds in Finland

Acta Veterinaria Scandinavica

Anu Katriina Lappalainen²  Katariina Mäki¹  Outi Laitinen-Vapaavuori² 

[1] Finnish Kennel Club, Kamreerintie 8, Espoo, 02770, Finland

[2] Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, 00014, Finland

关键词: Heritability;    Genetic trend;    Radiographic screening;    Intervertebral disc calcification;    Intervertebral disc disease;    Dachshund;    Canine;   

Others  :  1234909
DOI  :  10.1186/s13028-015-0170-7

 received in 2014-08-18, accepted in 2015-11-13,  发布年份 2015

【 摘 要 】

Background

Intervertebral disc disease (IDD) is a hereditary condition particularly common in Dachshunds. The breed is predisposed to early intervertebral disc degeneration and intervertebral disc calcification (IDC). When calcified, these severely degenerated discs are visible in spinal radiographs. Since the number of calcified discs (NCD) is associated with IDD, spinal radiography can be utilized in screening programmes in attempts to diminish the incidence of IDD in Dachshunds. Our aims were to estimate the heritability and genetic trend of NCD in Dachshunds in Finland and to explore the effect of age at the time of radiographic screening. Since the NCD has a highly skewed distribution, a log-transformed NCD (lnNCD) was also used as an analysed trait. The variance components for both traits were estimated, using the restricted maximum likelihood method. The fixed effects of breed variant, sex, as well as year of screening and the random effects of litter and animal were included in the model. The genetic trends in the NCD and lnNCD were assessed from the estimated breeding values (EBVs) of individual dogs by comparing the mean EBV of dogs born in different years. The breeding values were estimated, using the best linear unbiased prediction animal model. The pedigree in the genetic analyses included a total of 9027 dogs, of which 1567 showed results for NCDs.

Results

The heritability estimates of the NCD and lnNCD in Dachshunds were high (0.53 and 0.45, respectively). Small genetic improvements were seen as the mean EBVs increased from 100 to 104 and 105 over a 15-year period. The gain in the entire Dachshund population in Finland may differ from that observed, since less than 10 % of the Dachshunds registered have a screening result for NCD. Age at the time of the screening did not significantly affect the NCD or lnNCD.

Conclusions

We recommend systematic radiographic screening for IDC in Dachshunds and adopting EBVs as a tool for selecting breeding dogs. Age at the time of the radiographic screening may not be as important as previously suggested.

【 授权许可】

   
2015 Lappalainen et al.

【 图 表 】

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