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Ottmar Distl - One of the best experts on this subject based on the ideXlab platform.
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refinement of quantitative trait loci on equine chromosome 10 for radiological signs of Navicular Disease in hanoverian warmblood horses
Animal Genetics, 2010Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Summary Navicular Disease is characterized by a progressive degenerative alteration of the equine podotrochlea. In this study, we refined a previously identified quantitative trait locus (QTL) on horse chromosome 10 for the abnormal development of canales sesamoidales (DCS) of the Navicular bone in Hanoverian warmblood horses. Genotyping was done in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The whole marker set comprised 45 markers including seven newly developed microsatellites and 13 single nucleotide polymorphisms (SNPs) within positional candidate genes. Chromosome-wide significant QTL were confirmed and refined for DCS on horse chromosome (ECA) 10 at 0.16–2.70 Mb and at 14.45–36.37 Mb. Nine microsatellites and three SNP markers reached the highest multipoint Zmeans and LOD scores at 19.34–20.38 Mb and at 23.17–30.73 Mb with genome-wide error probabilities of P < 0.05. In addition, a significant association of a SNP within VSTM1 and a significant haplotype-trait association within IRF3 could be shown. These results support a possible role of the candidate genes VSTM1 and IRF3 within the QTL on ECA10 for DCS. This study is a further step towards the identification of the genes responsible for Navicular Disease in Hanoverian warmblood horses.
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Refinement of quantitative trait loci on equine chromosome 10 for radiological signs of Navicular Disease in Hanoverian warmblood horses.
Animal genetics, 2010Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Navicular Disease is characterized by a progressive degenerative alteration of the equine podotrochlea. In this study, we refined a previously identified quantitative trait locus (QTL) on horse chromosome 10 for the abnormal development of canales sesamoidales (DCS) of the Navicular bone in Hanoverian warmblood horses. Genotyping was done in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The whole marker set comprised 45 markers including seven newly developed microsatellites and 13 single nucleotide polymorphisms (SNPs) within positional candidate genes. Chromosome-wide significant QTL were confirmed and refined for DCS on horse chromosome (ECA) 10 at 0.16-2.70 Mb and at 14.45-36.37 Mb. Nine microsatellites and three SNP markers reached the highest multipoint Zmeans and LOD scores at 19.34-20.38 Mb and at 23.17-30.73 Mb with genome-wide error probabilities of P
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Fine mapping a quantitative trait locus on horse chromosome 2 associated with radiological signs of Navicular Disease in Hanoverian warmblood horses
Animal genetics, 2009Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Navicular Disease or podotrochlosis is one of the main causes of progressive forelimb lameness in warmblood horses. The objective of this study was to refine a quantitative trait locus on horse chromosome 2 for radiological alterations in the contour of the Navicular bone (RAC) in Hanoverian warmblood horses. Genotyping was performed in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The marker set was extended to 58 informative microsatellites including nine newly developed microsatellites. QTL for RAC could be delineated at 32.50-43.13 Mb and a further new QTL for RAC could be identified at 59.08-65.14 Mb. The markers ABGe342 and ABGe343 reached the highest multipoint Z(mean) and LOD scores at 34.42 and 35.23 Mb with genome-wide error probabilities of P = 0.013 and P = 0.064. In addition, significant associations of markers and haplotypes within the QTL could be shown. The results support the location of the QTL on ECA2 associated with RAC. This work is a further step towards the development of a marker test for Navicular Disease in Hanoverian warmblood horses.
M S Lopes - One of the best experts on this subject based on the ideXlab platform.
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refinement of quantitative trait loci on equine chromosome 10 for radiological signs of Navicular Disease in hanoverian warmblood horses
Animal Genetics, 2010Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Summary Navicular Disease is characterized by a progressive degenerative alteration of the equine podotrochlea. In this study, we refined a previously identified quantitative trait locus (QTL) on horse chromosome 10 for the abnormal development of canales sesamoidales (DCS) of the Navicular bone in Hanoverian warmblood horses. Genotyping was done in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The whole marker set comprised 45 markers including seven newly developed microsatellites and 13 single nucleotide polymorphisms (SNPs) within positional candidate genes. Chromosome-wide significant QTL were confirmed and refined for DCS on horse chromosome (ECA) 10 at 0.16–2.70 Mb and at 14.45–36.37 Mb. Nine microsatellites and three SNP markers reached the highest multipoint Zmeans and LOD scores at 19.34–20.38 Mb and at 23.17–30.73 Mb with genome-wide error probabilities of P < 0.05. In addition, a significant association of a SNP within VSTM1 and a significant haplotype-trait association within IRF3 could be shown. These results support a possible role of the candidate genes VSTM1 and IRF3 within the QTL on ECA10 for DCS. This study is a further step towards the identification of the genes responsible for Navicular Disease in Hanoverian warmblood horses.
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Refinement of quantitative trait loci on equine chromosome 10 for radiological signs of Navicular Disease in Hanoverian warmblood horses.
Animal genetics, 2010Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Navicular Disease is characterized by a progressive degenerative alteration of the equine podotrochlea. In this study, we refined a previously identified quantitative trait locus (QTL) on horse chromosome 10 for the abnormal development of canales sesamoidales (DCS) of the Navicular bone in Hanoverian warmblood horses. Genotyping was done in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The whole marker set comprised 45 markers including seven newly developed microsatellites and 13 single nucleotide polymorphisms (SNPs) within positional candidate genes. Chromosome-wide significant QTL were confirmed and refined for DCS on horse chromosome (ECA) 10 at 0.16-2.70 Mb and at 14.45-36.37 Mb. Nine microsatellites and three SNP markers reached the highest multipoint Zmeans and LOD scores at 19.34-20.38 Mb and at 23.17-30.73 Mb with genome-wide error probabilities of P
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Fine mapping a quantitative trait locus on horse chromosome 2 associated with radiological signs of Navicular Disease in Hanoverian warmblood horses
Animal genetics, 2009Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Navicular Disease or podotrochlosis is one of the main causes of progressive forelimb lameness in warmblood horses. The objective of this study was to refine a quantitative trait locus on horse chromosome 2 for radiological alterations in the contour of the Navicular bone (RAC) in Hanoverian warmblood horses. Genotyping was performed in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The marker set was extended to 58 informative microsatellites including nine newly developed microsatellites. QTL for RAC could be delineated at 32.50-43.13 Mb and a further new QTL for RAC could be identified at 59.08-65.14 Mb. The markers ABGe342 and ABGe343 reached the highest multipoint Z(mean) and LOD scores at 34.42 and 35.23 Mb with genome-wide error probabilities of P = 0.013 and P = 0.064. In addition, significant associations of markers and haplotypes within the QTL could be shown. The results support the location of the QTL on ECA2 associated with RAC. This work is a further step towards the development of a marker test for Navicular Disease in Hanoverian warmblood horses.
I. M. Wright - One of the best experts on this subject based on the ideXlab platform.
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Biomechanical considerations in the treatment of Navicular Disease.
The Veterinary record, 1993Co-Authors: I. M. Wright, J DouglasAbstract:In recent years much attention has been paid to vascular studies of the Navicular bone in health and Disease; however, the relative importance of these studies has overshadowed biomechanical factors which may yet prove to be of importance. This paper outlines the pertinent anatomy, and discusses current concepts in the aetiology and pathogenesis of the Disease. It describes the treatment regimens which are based on biomechanical considerations and compares the results of some currently employed techniques. All aspects of Navicular Disease remain controversial. This paper is not intended to review or debate all current information on the subject. It reviews information on only biomechanical considerations in an attempt to focus attention on these aspects of treatment.
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A study of 118 cases of Navicular Disease: radiological features.
Equine veterinary journal, 1993Co-Authors: I. M. WrightAbstract:Summary Dorsoproximal-palmarodistal oblique, lateromedial and palmaroproximal-palmarodistal oblique radiographic projections were used with standard techniques to examine 118 horses with clinical signs of Navicular Disease. All radiological features which have previously been reported as significant changes in the Navicular bones of horses with Navicular Disease were recorded. Comparisons were made between these features in lame limbs and sound limbs in unilaterally lame horses and most lame limbs and least lame limbs in bilateral but asymmetrically lame animals. Their relationship to the degree of lameness was also analysed. No relationships were identified between the characteristics of distal border synovial invaginations, flattening and/or thinning of the flexor cortex and limb distribution or severity of lameness. Defects in the flexor cortex, proximal border remodelling, medullary trabecular disruption and medullary sclerosis appeared to be related to limb affliction and severity of lameness while proximal border enthesophytes, and poor flexor corticomedullary demarcation presented evidence of a relationship to the grade of lameness. Poor flexor corticomedullary demarcation and fragmentation of the distal border were related to the severity of lameness in bilateral but asymmetrically affected horses. The presence of peri-articular osteophytes and mineralisation of the flexor digitorum profundus were too infrequently recognised to permit meaningful data evaluation.
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A study of 118 cases of Navicular Disease: treatment by Navicular suspensory desmotomy.
Equine veterinary journal, 1993Co-Authors: I. M. WrightAbstract:Summary The 118 horses diagnosed as suffering from Navicular Disease by prospective criteria were treated by desmotomy of the ligamenta sesamoidea collateralia (Navicular suspensory desmotomy). Three techniques were used and a standard post-operative programme was followed with clinical and radiological evaluations at 6-monthly intervals for periods of 6–36 months after surgery. At 6 and 36 months after treatment, 76% and 42.9% of horses were sound respectively. The clinical features of age, period of lameness, severity of lameness and angular limb deformities adversely affected response to surgery. The presence of flexor cortex defects, proximal border enthesophytes, mineralisation of the flexor digitorum profundus tendon and medullary sclerosis were also associated with a diminished response. There were few (1.7%) changes in the radiological appearance of distal border synovial invaginations during the follow-up period. By contrast, the majority (67.3%) of flexor cortex defects changed. Other radiological features changed at a low frequency but there was no association between radiological change and clinical outcome.
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A study of 118 cases of Navicular Disease: clinical features
Equine veterinary journal, 1993Co-Authors: I. M. WrightAbstract:Summary The clinical features are reported from 118 horses (mean age 9.2 years) which were diagnosed as suffering from Navicular Disease using predetermined criteria. The animals were used for a variety of purposes and had been lame for periods between 1 and 72 months. The majority of cases (84.7%) had been treated using various techniques before evaluation. The severity of lameness was related to the duration of clinical signs: 78% of horses were bilaterally affected but there was no left:right limb predominance. Broken foot/pastern axes were recorded in 75% of horses while 45% also exhibited mediolateral foot imbalance. Muscle atrophy was recognised in 77% of animals which appeared to be related to limb affliction. The cranial phase of the stride was reduced in 38% and caudal phase shortened in 16% of horses. These abnormalities were related to the degree of lameness. Flexion of the distal joints increased the severity of lameness in 64% of the animals while extension was positive in 41% of instances. Turning in the direction of the lame limb exacerbated lameness in 95% of horses. Only 11% of animals responded to the use of hoof testers and 3% to foot percussion. A range of responses to local analgesia of the palmar digital nerves was recorded but 91% (of 49) of animals exhibited a positive response to local analgesia of the distal interphalangeal joint, and 92% (of 23) of horses responded to local analgesia of the Navicular bursa.
U Diesterbeck - One of the best experts on this subject based on the ideXlab platform.
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refinement of quantitative trait loci on equine chromosome 10 for radiological signs of Navicular Disease in hanoverian warmblood horses
Animal Genetics, 2010Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Summary Navicular Disease is characterized by a progressive degenerative alteration of the equine podotrochlea. In this study, we refined a previously identified quantitative trait locus (QTL) on horse chromosome 10 for the abnormal development of canales sesamoidales (DCS) of the Navicular bone in Hanoverian warmblood horses. Genotyping was done in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The whole marker set comprised 45 markers including seven newly developed microsatellites and 13 single nucleotide polymorphisms (SNPs) within positional candidate genes. Chromosome-wide significant QTL were confirmed and refined for DCS on horse chromosome (ECA) 10 at 0.16–2.70 Mb and at 14.45–36.37 Mb. Nine microsatellites and three SNP markers reached the highest multipoint Zmeans and LOD scores at 19.34–20.38 Mb and at 23.17–30.73 Mb with genome-wide error probabilities of P < 0.05. In addition, a significant association of a SNP within VSTM1 and a significant haplotype-trait association within IRF3 could be shown. These results support a possible role of the candidate genes VSTM1 and IRF3 within the QTL on ECA10 for DCS. This study is a further step towards the identification of the genes responsible for Navicular Disease in Hanoverian warmblood horses.
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Refinement of quantitative trait loci on equine chromosome 10 for radiological signs of Navicular Disease in Hanoverian warmblood horses.
Animal genetics, 2010Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Navicular Disease is characterized by a progressive degenerative alteration of the equine podotrochlea. In this study, we refined a previously identified quantitative trait locus (QTL) on horse chromosome 10 for the abnormal development of canales sesamoidales (DCS) of the Navicular bone in Hanoverian warmblood horses. Genotyping was done in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The whole marker set comprised 45 markers including seven newly developed microsatellites and 13 single nucleotide polymorphisms (SNPs) within positional candidate genes. Chromosome-wide significant QTL were confirmed and refined for DCS on horse chromosome (ECA) 10 at 0.16-2.70 Mb and at 14.45-36.37 Mb. Nine microsatellites and three SNP markers reached the highest multipoint Zmeans and LOD scores at 19.34-20.38 Mb and at 23.17-30.73 Mb with genome-wide error probabilities of P
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Fine mapping a quantitative trait locus on horse chromosome 2 associated with radiological signs of Navicular Disease in Hanoverian warmblood horses
Animal genetics, 2009Co-Authors: M S Lopes, U Diesterbeck, A Da Câmara Machado, Ottmar DistlAbstract:Navicular Disease or podotrochlosis is one of the main causes of progressive forelimb lameness in warmblood horses. The objective of this study was to refine a quantitative trait locus on horse chromosome 2 for radiological alterations in the contour of the Navicular bone (RAC) in Hanoverian warmblood horses. Genotyping was performed in 192 Hanoverian warmblood horses from 17 paternal half-sib groups. The marker set was extended to 58 informative microsatellites including nine newly developed microsatellites. QTL for RAC could be delineated at 32.50-43.13 Mb and a further new QTL for RAC could be identified at 59.08-65.14 Mb. The markers ABGe342 and ABGe343 reached the highest multipoint Z(mean) and LOD scores at 34.42 and 35.23 Mb with genome-wide error probabilities of P = 0.013 and P = 0.064. In addition, significant associations of markers and haplotypes within the QTL could be shown. The results support the location of the QTL on ECA2 associated with RAC. This work is a further step towards the development of a marker test for Navicular Disease in Hanoverian warmblood horses.
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Review of genetic aspects of radiological alterations in the Navicular bone of the horse.
DTW. Deutsche tierarztliche Wochenschrift, 2007Co-Authors: U Diesterbeck, O DistlAbstract:Navicular Disease or podotrochlosis has long been known to cause forelimb lameness in horses. It had been proposed that the development of podotrochlosis has similarities to the human osteoarthritis (OA) complex. Alterations of the Navicular bone can be made visible early in life only on the basis of radiographs. Reports on the prevalences of Navicular Disease indicate that radiological alterations in the Navicular bone are present in different warmblood populations at frequencies of between 14.9% and 87.6%. Genetic factors play an important role in the development of the radiological signs. Estimates of heritability using animal threshold models range from h2 = 0.09 to h2 = 0.40. Estimated additive genetic correlations between radiological changes in the Navicular bone and other orthopaedic health traits indicated that they mostly develop genetically independently of each other. There was a negative genetic correlation between radiological changes in the Navicular bone and the number of tournament entries and placings. It has also been shown that reduction of radiological changes of Navicular bones and improvement of breeding values for performance of riding horses can be achieved if selection is based on breeding values for these traits simultaneously. An optimised markerset was developed to detect quantitative trait loci (QTL) for pathologic changes in the Navicular bone of Hanoverian warmblood horses. The horse genome was scanned using 214 highly polymorphic microsatellites chromosome-wide significant QTL were located on equine chromosomes (ECA) 2, 3, 4, 10, and 26. Genome-wide significant QTL were on ECA2 and on ECA10. Unravelling QTL associated with Navicular Disease will enhance selection progress for a healthy limb constitution in horses.
J. Van Den Broek - One of the best experts on this subject based on the ideXlab platform.
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Relationships of age and shape of the Navicular bone to the development of Navicular Disease: a radiological study.
Equine veterinary journal, 2010Co-Authors: K J Dik, A. J. M. Van Den Belt, J. Van Den BroekAbstract:Summary Estimating the shape of the proximal articular border of the Navicular bone and grading the radiological Navicular bone condition (grades 3 and 4 representing the most severe changes), the aim of this study was to assess potential age-related implications of the previously reported shape predisposition to Navicular Disease in 746 normal and 174 clinically affected Dutch Warmbloods age 3–19 years. A significant, age-independent, shape-grade association found in normal and affected horses emphasises the fundamental character of the shape predisposition to Navicular Disease. A significant age-related increase of the least susceptible shape prevalence was found in elderly normal horses. A shape-independent low grades 3 and 4 prevalence (mean 15%) was found in normal horses, vs. a high grades 3 and 4 prevalence (mean 85%) in the affected horses. Therefore, the clinical manifestation of the Disease is grade-rather than shape-dependent. A significant age-related appearance of inverted flask-shaped channels and enthesophytes was found in the clinically affected horses. However, considering the significant shape-radiological features association previously reported in 3-year-old normal horses, this association may be shape- rather than age-dependent.
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Role of Navicular bone shape in the pathogenesis of Navicular Disease: a radiological study.
Equine veterinary journal, 1995Co-Authors: K J Dik, J. Van Den BroekAbstract:Summary From progeny lists of 30 Dutch Warmblood sires, 586 3-year-old females by these stallions were randomly selected, each progeny group aimed at 20 animals for statistical reasons. The front feet of the sires and female progeny were examined radiographically using lateromedial and dorsopalmar upright pedal projections. The radiological features associated with Navicular Disease were classified 0–4 using a standardised classification, grades 3 and 4 representing the more severe changes. The shape of the proximal articular border of the Navicular bone outlined on the dorsopalmar view was classified 1–4: l=concave; 2=undulating; 3=straight; 4=convex. A significant shape-grade association was found, the highest grades 3 and 4 incidence associated with shape 1 and the lowest grades 3 and 4 incidence demonstrated by shape 4. In shapes 1 and 2, Navicular bones grades 3 and 4 features were mainly characterised by inverted flask-shaped channels. In shape 3, Navicular bones grades 3 and 4 were dominated by enthesiophytes. These findings indicate an apparent shape predisposition to radiological changes associated with Navicular Disease. The shape of the Navicular bone in the offspring was on average the same as the sire, indicating an hereditary element in Navicular bone shape.
