| 1. |
- Arvelius, Per, et al.
(författare)
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Measuring herding behavior in Border collie - effect of protocol structure on usefulness for selection
- 2013
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Ingår i: Journal of Veterinary Behavior: Clinical Applications and Research. - : Elsevier BV. - 1558-7878 .- 1878-7517. ; 8, s. 9-18
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Tidskriftsartikel (refereegranskat)abstract
- From 1989 until 2003, the Swedish Sheepdog Society used a standardized method, Herding Trait Characterization (HTC), to describe herding behavior of individual Border collies for breeding purposes. In the HTC, which existed in 2 consecutive versions, the dog's herding behavior was described using predefined scales typically consisting of 6 classes within each trait. In total, 1,663 dogs participated in the first version and 951 in the second. The main difference between the versions was the structure of the protocols used to record the traits. In the first version, the scales were designed to describe the intensity in the expression of the measured traits. In the second version, the most desirable behavioral expression was placed in the middle of the scale. Another difference was that in the second version, the judges were given more freedom for their own interpretations, that is, the scales were more subjective. The objective of this study was to examine the quality of each version from a breeding perspective, and to analyze the reasons for possible differences in this respect between them. Heritability estimates for the 17 traits of the earlier version of the HTC ranged from 0.14 to 0.50 (weighted average: 0.30), all significantly different from 0. Corresponding heritabilities for the 19 traits in the later version were substantially lower (0.03-0.41, weighted average: 0.16), 3 of them not being significantly different from 0. Owing to the moderate-to-high heritabilities for the traits measured in the earlier version of the HTC, it would be possible to accomplish effective selection of breeding animals for most of the measured traits. It is plausible that the less neutral and more subjective protocol of the later version is the main cause for the lower heritabilities. (C) 2013 Elsevier Inc. All rights reserved.
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| 2. |
- Malm, Sofia, et al.
(författare)
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Association between radiographic assessment of hip status and subsequent incidence of veterinary care and mortality related to hip dysplasia in insured Swedish dogs
- 2010
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 93, s. 222-232
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Tidskriftsartikel (refereegranskat)abstract
- Our objective was to evaluate the association between grading of hip status as assessed by radiographic examination (hip screening) and subsequent incidence of veterinary care and mortality related to hip dysplasia (HD) in five breeds of insured dogs in Sweden. Screening results for hip status from the Swedish Kennel Club and data on veterinary care and mortality from the insurance company Agria were merged based on the registration number of the dog. Dogs of five breeds (Bernese Mountain Dogs, German Shepherds, Golden Retrievers, Labrador Retrievers, and Rottweilers) screened during 1995-2004 and covered by an insurance plan for veterinary care or life at the time of screening were included. The study populations included between 1667 and 10,663 dogs per breed. Breed-specific multivariable Cox proportional-hazards analyses were performed to evaluate the impact of radiographic hip status on time from hip screening to first HD-related veterinary and life claim, respectively. The effects of gender, birth season, and a time-varying covariate of year were also studied. Additional analyses, on the five breeds combined, were performed to investigate the effects of hip status, breed, and the interaction between hip status and breed. The effect of hip status was highly significant (P < 0.001) for both life and veterinary claims related to HD in all five breeds with increased hazard ratio (HR) for deteriorating hip status. Dogs with moderate or severe hip status at screening had a markedly increased hazard of HD-related veterinary care and mortality compared with dogs assessed as free or mild. The time-varying covariate of year showed a significantly higher HR in the last time period for German Shepherds and Labrador Retrievers in the analyses of veterinary claims. In the analyses on all five breeds, German Shepherds had the highest HR for both veterinary care and mortality related to HD, followed by Bernese Mountain Dogs. Golden and Labrador Retrievers had the lowest HR. The effect of hip status on the hazard was the same irrespective of breed. However, as a consequence of differences between breeds in overall risk, the predictive ability of screening results for subsequent incidence of HD-related problems for individual dogs was breed-dependent. Based on the strong association between radiographic hip status and incidence of HD-related veterinary care and mortality, and the previously reported moderate heritability of hip status, we conclude that selection based on screening results for hip status can be expected to reduce the risk of HD-related clinical problems. (C) 2009 Elsevier B.V. All rights reserved.
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| 3. |
- Malm, Sofia, et al.
(författare)
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Efficient selection against categorically scored hip dysplasia in dogs is possible using best linear unbiased prediction and optimum contribution selection: a simulation study
- 2013
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Ingår i: Journal of Animal Breeding and Genetics. - : Wiley. - 0931-2668 .- 1439-0388. ; 130, s. 154-164
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Tidskriftsartikel (refereegranskat)abstract
- Breeding to reduce the prevalence of categorically scored hip dysplasia (HD), based on phenotypic assessment of radiographic hip status, has had limited success. The aim of this study was to evaluate two selection strategies for improved hip status: truncation selection based on phenotypic record versus best linear unbiased prediction (BLUP), using stochastic simulation and selection scenarios resembling those in real dog populations. In addition, optimum contribution selection (OCS) was evaluated. Two traits were considered: HD (as a categorical trait with five classes and a heritability of 0.45 on the liability scale) and a continuous trait (with a heritability of 0.25) intended to represent other characteristics in the breeding goal. A population structure mimicking that in real dog populations was modelled. The categorical nature of HD caused a considerably lower genetic gain compared to simulating HD as a continuous trait. Genetic gain was larger for BLUP selection than for phenotypic selection in all scenarios. However, BLUP selection resulted in higher rates of inbreeding. By applying OCS, the rate of inbreeding was lowered to about the same level as phenotypic selection but with increased genetic improvement. For efficient selection against HD, use of BLUP breeding values should be prioritized. In small populations, BLUP should be used together with OCS or similar strategy to maintain genetic variation.
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| 4. |
- Wang, Shizhi, et al.
(författare)
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Breeding policies and management of pedigree dogs in 15 national kennel clubs
- 2018
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Ingår i: Veterinary Journal. - : Elsevier BV. - 1090-0233 .- 1532-2971. ; 234, s. 130-135
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Tidskriftsartikel (refereegranskat)abstract
- To improve the health and welfare of pedigree dogs, national kennel clubs (KCs) are key players in the governance and regulation of dog breeding. In a survey conducted to investigate differences between KCs in breeding policies and management of pedigree dogs, a questionnaire was completed by 15 KCs from 11 European countries (Austria, Belgium, Denmark, France, Germany, Ireland, Latvia, The Netherlands, Norway, Sweden and the United Kingdom) and four non-European countries (Australia, Mexico, Uruguay and the USA). The most important concerns reported by KCs were exaggerated morphological features and inherited disorders. A wide variety of information, tools and strategies was used to address these issues, with implementation differing across countries and breeds. KCs reported progress in the collection and provision of information related to canine health and welfare. Implementation of advanced breeding tools, such as genetic evaluation and online advisory mating tools, and balanced breeding strategies, endorsed by clubs and breeders, remain challenging and require further development. (C) 2018 Elsevier Ltd. All rights reserved.
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| 5. |
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| 6. |
- Wang, Shizhi, et al.
(författare)
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Genetic correlations of hip dysplasia scores for Golden retrievers and Labrador retrievers in France, Sweden and the UK
- 2017
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Ingår i: Veterinary Journal. - : Elsevier BV. - 1090-0233 .- 1532-2971. ; 226, s. 51-56
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Tidskriftsartikel (refereegranskat)abstract
- In order to reduce the prevalence of inherited diseases in pedigree dogs, the feasibility of implementation of an international breeding program was investigated. One prerequisite is a strong genetic correlation between countries and our objective was to estimate this correlation for canine hip dysplasia (HD) across three countries to evaluate the feasibility of an international genetic evaluation. Data were provided by the Societe Centrale Canine (SCC, France), Svenska Kennelklubben (SKK, Sweden) and The Kennel Club (KC, UK) on Golden retriever and Labrador retriever dogs. Trivariate analysis on the three different modes of scoring HD in France, Sweden and the UK was performed using a mixed linear animal model. Heritability, genetic correlation, number of common sires, genetic similarity, selection differentials and accuracy of selection were calculated.The estimated heritabilities of Golden retrievers (Labrador retrievers) for HD scores were 0.28 (0.15), 0.28 (0.29) and 0.41 (0.34) in France, Sweden and the UK, respectively. The feasibility of performing a genetic evaluation of HD across countries was indicated by the favourable genetic correlations estimated between score modes (ranged from 0.48 to 0.99). The accuracy of selection for the most recent birth year cohorts of male dogs was not improved by international evaluation compared to national evaluation. Improvement in genetic progress can however be achieved by selection across populations in different countries, particularly for small populations, which were indicated by the large difference between selection differentials based on the national and international evaluations. (C) 2017 Elsevier Ltd. All rights reserved.
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| 7. |
- Wang, Shizhi, et al.
(författare)
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Genetic improvement of canine hip dysplasia through sire selection across countries
- 2019
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Ingår i: Veterinary Journal. - : Elsevier BV. - 1090-0233 .- 1532-2971. ; 248, s. 18-24
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Tidskriftsartikel (refereegranskat)abstract
- Breeding against canine hip dysplasia (HD) may benefit from the importation of foreign sires. When foreign sires are evaluated on a different HD scale, this may diminish the efficacy. Using stochastic simulations, we evaluated genetic change and inbreeding levels for different scenarios of importing sires with high genetic merit for HD. Population size and genetic parameters (e.g. heritability, accuracy of selection, genetic correlation) were based on actual data for HD in Golden retrievers and Labrador retrievers in the UK and Sweden.For countries with different HD scales and an estimated breeding value (EBV) evaluation in place, the importation was useful if imported sires had EBV rankings in the top 50% and if genetic correlations between EBV systems were above 0.85. When importing sires with EBV rankings in the top 10%, moderate accuracies of EBVs (>0.40) and moderately strong genetic correlations (>0.70) were needed. Selection against HD without the importation of sires may increase inbreeding levels, while the importation of sires can decrease inbreeding levels. For national genetic evaluation and selection programmes, importing sires with high genetic merit can be an effective breeding strategy, but care is needed to estimate reliable EBVs. (C) 2019 Elsevier Ltd. All rights reserved.
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| 8. |
- Wang, Shizhi, et al.
(författare)
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Merging pedigree databases to describe and compare mating practices and gene flow between pedigree dogs in France, Sweden and the UK
- 2017
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Ingår i: Journal of Animal Breeding and Genetics. - : Wiley. - 0931-2668 .- 1439-0388. ; 134, s. 152-161
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Tidskriftsartikel (refereegranskat)abstract
- Merging pedigree databases across countries may improve the ability of kennel organizations to monitor genetic variability and health-related issues of pedigree dogs. We used data provided by the Societe Centrale Canine (France), Svenska Kennelklubben (Sweden) and the Kennel Club (UK) to study the feasibility of merging pedigree databases across countries and describe breeding practices and international gene flow within the following four breeds: Bullmastiff (BMA), English setter (ESE), Bernese mountain dog (BMD) and Labrador retriever (LBR). After merging the databases, genealogical parameters and founder contributions were calculated according to the birth period, breed and registration country of the dogs. Throughout the investigated period, mating between close relatives, measured as the proportion of inbred individuals (considering only two generations of pedigree), decreased or remained stable, with the exception of LBR in France. Gene flow between countries became more frequent, and the origins of populations within countries became more diverse over time. In conclusion, the potential to reduce inbreeding within purebred dog populations through exchanging breeding animals across countries was confirmed by an improved effective population size when merging populations from different countries.
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