Pedigree analysis in horses involves the study of lineage and ancestry to understand genetic relationships and inheritance patterns. It is a tool used to track traits, performance potential, and hereditary diseases within horse populations. Pedigree records often include detailed information on the ancestors of a horse, going back several generations, and can help in making informed breeding decisions. This page assembles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and implications of pedigree analysis in equine breeding and genetics.
Holl HM, Brooks SA, Archer S, Brown K, Malvick J, Penedo MC, Bellone RR.Leopard complex spotting (LP), the result of an incompletely dominant mutation in TRPM1, produces a collection of unique depigmentation patterns in the horse. Although the LP mutation allows for expression of the various patterns, other loci are responsible for modification of the extent of white. Pedigree analysis of families segregating for high levels of patterning indicated a single dominant gene, named Pattern-1 (PATN1), as a major modifier of LP. Linkage analysis in two half-sibling families segregating for PATN1 identified a 15-Mb region on ECA3p that warranted further investigation. Wh...
Brard S, Ricard A.An A/C mutation responsible for the ability to pace in horses was recently discovered in the gene. It has also been proven that allele C has a negative effect on trotters' performances. However, in French trotters (FT), the frequency of allele A is only 77% due to an unexpected positive effect of allele C in late-career FT performances. Here we set out to ascertain whether the genotype at SNP (linked to ) should be used to compute EBV for FT. We used the genotypes of 630 horses, with 41,711 SNP retained. The pedigree comprised 5,699 horses. Qualification status (trotters need to complete a 2,0...
Criscione A, Moltisanti V, Chies L, Marletta D, Bordonaro S.Salernitano (SAL) is an ancient Italian horse breed developed over the course of the ages together with Napoletano and, during the 20th century, by crossing with Thoroughbred horse lines. Excellent in hurdle jumping, this breed is currently facing a concrete risk of extinction due to the lack of appropriate management strategies. This research is the first SAL genetic characterization that aims to set up the basic knowledge for a conservation plan. A representative sample of 61 SALs was analyzed by means of a set of 16 microsatellites markers (short tandem repeats (STRs)). The sequence of hype...
Sharman P, Wilson AJ.Previous studies have concluded that thoroughbred racehorse speed is improving very slowly, if at all, despite heritable variation for performance and putatively intensive selective breeding. This has led to the suggestion that racehorses have reached a selection limit. However, previous studies have been limited, focusing only on the winning times of a few elite races run over middle and long distances, and failing to account for potentially confounding factors. Using a much larger dataset covering the full range of race distances and accounting for variation in factors such as ground softnes...
Rovere G, Madsen P, Norberg E, van Arendonk JA, Ducro BJ.Recent studies on data from the Dutch Warmblood Studbook (KWPN) have shown that the ongoing specialization of horses for either dressage (DH) or show jumping (JH) has led to a decreasing genetic relationship between the two subpopulations. The aim of this study was to analyse the effect of the specialization process on the genetic parameters of traits measured in the studbook-entry inspection of KWPN during the last fifteen years. Data from 18,125 DH and 23,800 JH recorded from 1998 until 2013 were used to analyse 13 traits scored in both DH and JH. Analyses were performed in a Bayesian framew...
Lin X, Zhou S, Wen L, Davie A, Yao X, Liu W, Zhang Y.Many studies have focused on identifying the genes or single nucleotide polymorphisms associated with the athletic ability of thoroughbreds, but few have considered differences in maternal and paternal heritability of athletic ability. Herein, we report on our association study of career race performances of 675 Australian thoroughbreds with their pedigrees. Racing performance data (prize money per start) were collected from the Bloodhound database. The performance of all horses was categorised as either poor or elite athletic achievement. Then, 675 foals were divided by their parents' perform...
Lopes MS, Mendonça D, Rojer H, Cabral V, Bettencourt SX, da Câmara Machado A.The Terceira Pony is a horse indigenous to Terceira Island in the Azores. These horses were very important during the colonization of the island. Due to their very balanced proportions and correct gaits, and with an average withers height of 1.28 m, the Terceira Pony is often confused with a miniature pure-bred Lusitano. This population was officially recognized as the fourth Portuguese equine breed by the national authorities in January, 2014. The aim of this study was to analyze the morphology and the genetic diversity by means of microsatellite markers of this emerging horse breed. The biom...
Lassaline M, Cranford TL, Latimer CA, Bellone RR.To describe the prevalence of LSCC in Haflinger horses and to analyze affected horses' pedigrees investigating the genetic mode of inheritance. Methods: Fifteen horses met inclusion criterion of (i) being of the Haflinger breed, as confirmed by North American Haflinger Registry pedigree and (ii) being diagnosed with LSCC, as confirmed by clinical examination by a veterinary ophthalmologist or by histopathology. Pedigrees could not be obtained for four additional horses diagnosed with LSCC that had been identified as Haflingers. Methods: Retrospective medical record review of all 19 horses was ...
Silva AP, Curi RA, Langlois B, Silva JA.In this study, we estimated the heritability (h(2)) of earnings in the Quarter Horse in order to evaluate the inclusion of this trait in breeding programs. Records from 14,754 races of 2443 horses from 1978-2009 were provided by Sorocaba Hippodrome, São Paulo, Brazil. All ancestors of the registered horses were included in the pedigree file until the 4th generation. Log-transformed performance measures (LPM) were analyzed for animals aged 2, 3, and 4 years and during their entire career. The h(2) estimates were obtained using a multi-trait model and Gibbs sampling that included the effects of...
Takasu M, Ishihara N, Tozaki T, Kakoi H, Maeda M, Mukoyama H.To determine genetic characteristics of the maternal lineage of the Kiso horse based on polymorphisms of the mitochondrial DNA D-loop region, we collected blood samples from 136 Kiso horses, 91% of the entire population, and sequenced 411 bp from 15,437 to 15,847 in the region. First of all, we estimated the demographic history; by searching homology between the obtained and known sequences using Basic Local Alignment Search Tool, by mismatch analysis to evaluate the mutation processes using Arlequin, and by building a phylogenetic tree showing the relationship of the mtDNA haplotypes for 24 h...
Bigi D, Perrotta G, Zambonelli P.To understand the origin and genetic diversity of Italian horses, mitochondrial DNA D-loop sequences were generated for 163 horses from seven breeds. Sequence analysis of a 480-bp segment revealed a total of 84 haplotypes with 57 polymorphic sites, indicating multiple maternal origins and high genetic diversity. Comparison of the haplotypes with the equine mtDNA haplotype/haplogroup nomenclature showed a haplogroup distribution in the Italian breeds more similar to that found in the Middle East breeds than in the European breeds, probably due to the economic and cultural relationship with the ...
Velie BD, Hamilton NA, Wade CM.Different indicators of racing performance are commonly used in the racing industry to assess the genetic superiority of racing Thoroughbreds. However, how well these indicators predict the performance of future progeny or siblings varies depending on the population and circumstances in which the indicators were recorded or achieved. Objective: To identify heritable indicators of racing performance for horses racing in Hong Kong. Methods: Heritability analysis of racing performance traits. Methods: Performance data on the population of Thoroughbreds racing in Hong Kong between 3 September 2000...
Sánchez Guerrero MJ, Cervantes I, Valera M, Gutiérrez JP.The most popular use of the Pura Raza Español horse in sport is for dressage competitions. Tests on young sport horses were first established in 2004 in Spain to collect data for the genetic evaluation of this breed's suitability for dressage. The aim of this study was to compare eight different models to find out the most appropriate way to include the rider in the genetic evaluation of dressage. A progressive removal of systematic effects from model was also analysed. A total of 8867 performance records collected between 2004 and 2011 from 1234 horses aged between 4 and 6 years old were use...
Lassaline-Utter M, Gemensky-Metzler AJ, Scherrer NM, Stoppini R, Latimer CA, MacLaren NE, Myrna KE.To describe the clinical presentation, treatment, and outcome of a corneal dystrophy in Friesian horses and to analyze affected horses' pedigrees to investigate its heritability. Methods: Nine Friesians with bilateral disease were identified. Methods: Retrospective medical record review was used to identify Friesian horses exhibiting bilateral symmetric corneal lesions. Variables identified from medical records included patient sex and age at diagnosis; location, depth and size of corneal lesions; medical and surgical therapy instituted; and visual outcome. A four-generation pedigree for each ...
Fornal A, Radko A, Piestrzyńska-Kajtoch A.Short tandem repeat (STR) loci, i.e. microsatellites are a class of genetic markers commonly used for population studies and parentage control. This study determined the usefulness of microsatellite markers recommended by International Society for Animal Genetics (ISAG) for identification and pedigree analysis in horses based on the example of Polish Hucul horse population (Equus caballus). The set of seventeen microsatellites loci was tested (AHT4, AHT5, ASB2, HMS2, HMS3, HMS6, HMS7, HTG10, HTG4, HTG6, HTG7, VHL20, ASB17, ASB23, CA425, HMS1, LEX3) for 216 individuals. All samples were genotyp...
Christen G, Gerber V, Dolf G, Burger D, Koch C.The mode of inheritance for susceptibility to equine sarcoid disease (ES) remains unknown. The objectives of this study were to analyse a large sample of the Franches-Montagnes (FM) horse population and investigate the heritability and mode of inheritance for susceptibility to ES. Horses were clinically examined for the presence of sarcoid tumours. A standardized examination protocol and client questionnaire were used and a pedigree- and subsequent segregation-analysis for the ES trait performed. To investigate the mode of inheritance, five models were evaluated and compared in a hierarchical ...
Khanshour AM, Cothran EG.Maternal inheritance is an essential point in Arabian horse population genetics and strains classification. The mitochondrial DNA (mtDNA) sequencing is a highly informative tool to investigate maternal lineages. We sequenced the whole mtDNA D-loop of 251 Arabian horses to study the genetic diversity and phylogenetic relationships of Arabian populations and to examine the traditional strain classification system that depends on maternal family lines using native Arabian horses from the Middle East. Results: The variability in the upstream region of the D-loop revealed additional differences amo...
Liu G, Xu CQ, Cao Q, Zimmermann W, Songer M, Zhao SS, Li K, Hu DF.Przewalski's horses have been imported from the western zoos to China since 1985. Yet the genetic diversity in China's populations has not been studied, thus lacking of such knowledge inevitably affects this population's management. The aim of this study was to assess genetic diversity in Chinese population of Przewalski's horses via mitochondrial DNA (mtDNA) control region and pedigree analysis. Methods: Two captive and one reintroduced populations were examined based on mitochondrial DNA control region variation via fecal sampling from 2010 to 2012, together with pedigree analysis. Results: ...
Janova E, Futas J, Klumplerova M, Putnova L, Vrtkova I, Vyskocil M, Frolkova P, Horin P.The Old Kladruber horses arose in the 17th century as a breed used for ceremonial purposes. Currently, grey and black coat colour varieties exist as two sub-populations with different recent breeding history. As the population underwent historical bottlenecks and intensive inbreeding, loss of genetic variation is considered as the major threat. Therefore, genetic diversity in neutral and non-neutral molecular markers was examined in the current nucleus population. Fifty microsatellites, 13 single nucleotide polymorphisms (SNPs) in immunity-related genes, three mutations in coat colour genes an...
Pirault P, Danvy S, Verrier E, Leroy G.Since horse breeds constitute populations submitted to variable and multiple outcrossing events, we analyzed the genetic structure and gene flows considering horses raised in France. We used genealogical data, with a reference population of 547,620 horses born in France between 2002 and 2011, grouped according to 55 breed origins. On average, individuals had 6.3 equivalent generations known. Considering different population levels, fixation index decreased from an overall species FIT of 1.37%, to an average [Formula: see text] of -0.07% when considering the 55 origins, showing that most horse ...
Wallner B, Vogl C, Shukla P, Burgstaller JP, Druml T, Brem G.The paternally inherited Y chromosome displays the population genetic history of males. While modern domestic horses (Equus caballus) exhibit abundant diversity within maternally inherited mitochondrial DNA, no significant Y-chromosomal sequence diversity has been detected. We used high throughput sequencing technology to identify the first polymorphic Y-chromosomal markers useful for tracing paternal lines. The nucleotide variability of the modern horse Y chromosome is extremely low, resulting in six haplotypes (HT), all clearly distinct from the Przewalski horse (E. przewalskii). The most wi...
Leroy G, Mary-Huard T, Verrier E, Danvy S, Charvolin E, Danchin-Burge C.Effective population sizes of 140 populations (including 60 dog breeds, 40 sheep breeds, 20 cattle breeds and 20 horse breeds) were computed using pedigree information and six different computation methods. Simple demographical information (number of breeding males and females), variance of progeny size, or evolution of identity by descent probabilities based on coancestry or inbreeding were used as well as identity by descent rate between two successive generations or individual identity by descent rate. Results: Depending on breed and method, effective population sizes ranged from 15 to 133 ...
Solé M, Valera M, Gómez MD, Cervantes I, Fernández J.Limiting the inbreeding rate (∆F) while maximizing genetic gain for any trait of economic interest is especially important in small populations of local breeds, like the Menorca Horse. In this breed, dressage performance is important for the profitability of the breed and should be accounted in the selection criterion. The aim of this study was to assess if a breeding programme aiming at improved dressage performance is feasible in such a small breed. To perform the analysis, animals that were currently available for breeding (between 3 and 20 years) were used. Selection was based on the es...
Ricard A, Danvy S, Legarra A.Genomic evaluations often use as pseudo-phenotypes corrected means of progeny performances, like daughter yield deviations (DYD) in dairy species. In horse breeding, own performances are also available and performances from other relatives (as half sibs) may play an important part in the EBV because the number of progeny remains low, even for stallions. The first step for genomic selection in horses is therefore to generate pseudo-phenotypes for genomic analysis when parental or own information is considered. This work presents an easy method to compute deregressed EBV from regular pedigree-ba...
Finno CJ, Famula T, Aleman M, Higgins RJ, Madigan JE, Bannasch DL.Equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (NAD/EDM) is a neurodegenerative disorder affecting young horses of various breeds that resembles ataxia with vitamin E deficiency in humans, an inherited disorder caused by mutations in the alpha-tocopherol transfer protein gene (TTPA). To evaluate variants found upon sequencing TTPA in the horse, the mode of inheritance for NAD/EDM had to be established. Objective: NAD/EDM in the American Quarter Horse (QH) is caused by a mutation in TTPA. Methods: 88 clinically phenotyped (35 affected [ataxia score ≥2], 53 unaffected) QH...
Vandenplas J, Janssens S, Buys N, Gengler N.The aim of this study was to test the integration of external information, i.e. foreign estimated breeding values (EBV) and the associated reliabilities (REL), for stallions into the Belgian genetic evaluation for jumping horses. The Belgian model is a bivariate repeatability Best Linear Unbiased Prediction animal model only based on Belgian performances, while Belgian breeders import horses from neighbouring countries. Hence, use of external information is needed as prior to achieve more accurate EBV. Pedigree and performance data contained 101382 horses and 712212 performances, respectively....
Rushton J, Tichy A, Brem G, Druml T, Nell B.There are no studies on the ophthalmic health status in the Lipizzaner breed. Objective: To perform an ophthalmological survey in a closed herd in 3 housing systems. Methods: All horses at the Federal Stud Piber, Heldenberg and the Spanish Riding School Vienna were subjected to ophthalmological examination. Findings were documented and correlated with factors such as age, gender, location and housing situation. The interrelation of abnormalities of different regions was determined by calculating accuracy. Pedigree analysis of horses affected by cataract was performed. Results: A total of 267 h...
Bower MA, Whitten M, Nisbet RE, Spencer M, Dominy KM, Murphy AM, Cassidy R, Barrett E, Hill EW, Binns M.The potential future earnings and therefore value of Thoroughbred foals untested in the racing arena are calculated based on the performance of their forebears. Thus, lineage is of key importance. However, previous research indicates that maternally inherited mitochondrial DNA (mtDNA) does not correspond to maternal lineage according to recorded pedigree, casting doubt on the voracity of historic pedigrees. We analysed mtDNA of 296 Thoroughbred horses from 33 maternal lineages and identified an interesting trend. Subsequent to the founding of the Thoroughbred breed in the 16th century, well-po...
MacLeay JM, Valberg SJ, Sorum SA, Sorum MD, Kassube T, Santschi EM, Mickelson JR, Geyer CJ.To determine the likely mode of inheritance and identify probable foundation horses for recurrent exertional rhabdomyolysis (RER) in Thoroughbred (TB) racehorses. Methods: 4 families of TB racehorses with a high prevalence of RER, consisting of 3 to 53 horses/family, were used to determine mode of inheritance. Sixty-two TB horses with RER and 34 control TB racehorses without RER were used to identify probable foundation horses for the RER trait. Methods: RER was diagnosed by a veterinarian and verified by detecting high serum creatine kinase activity. Pedigrees dating from 1930 for all horses ...
Valberg SJ, Geyer C, Sorum SA, Cardinet GH.To trace pedigrees from affected horses, identify likely contributing founder horses, and determine the conditional probability of founder genotypes. Methods: Muscle biopsy records from the Neuromuscular Disease Laboratory at the University of California-Davis and the University of Minnesota were searched to identify horses with a polysaccharide storage myopathy and exercise intolerance/rhabdomyolysis. Pedigrees containing 5 to 6 generations were obtained where possible. Methods: 13 Quarter Horses, 4 American Paint Horses, 3 Appaloosas, and 3 Quarter Horse crossbreds (16 mares, 4 geldings, and...
Hermans WA, Kersjes AW, van der Mey GJ, Dik KJ.A breeding experiment was carried out in a group of Shetland ponies in order to investigate the heredity of congenital lateral patellar (sub)luxation. A breeding herd was established and consisted of stallions and mares acquired at different times. Some were free from, and others were affected by lateral patellar (sub)luxation in either one or both femoropatellar joints. Over a period of 20 years, 49 foals were born from different mating combinations. Some offspring were free from the defect and others showed the abnormality. Though the number of foals bred during the experiment is rather smal...
Trachsel DS, Calloe K, Mykkänen AK, Raistakka P, Anttila M, Fredholm M, Tala M, Lamminpää K, Klaerke DA, Buhl R.Exercise-associated sudden deaths (EASDs) are deaths occurring unexpectedly during or immediately after exercise. Sudden cardiac death (SCD) is one cause of EASD. Cardiac arrhythmias caused by genetic variants have been linked to SCD in humans. We hypothesize that genetic variants may be associated with SCD in animals, including horses. Genetic variants are transmitted to offspring and their frequency might increase within a family. Therefore, the frequency of such variants might increase with the inbreeding factor. Higher inbreeding could have a negative impact on racing performance. Pedigree...
Kraus M, Physick-Sheard P, Brito LF, Sargolzaei M, Schenkel FS.Admissions of Standardbred racehorses (Std) to the Ontario Veterinary College Teaching Hospital (OVCTH) for treatment of atrial fibrillation (AF) began to increase in the early 1990s. The arrhythmia has been shown to have a modest heritability (h2 ≃ 0.15), with some stallions appearing as sires or sires of mares used in breeding (broodmares) of affected horses more frequently than others. The objective of this study was to determine the marginal genetic contributions of ancestors to cohorts of Std affected with AF and their contemporary control groups, and whether these ancestors contribute ...
Amjadi MA, Yeganeh HM, Sadeghi M, Abbas Raza SH, Yang J, Najafabadi HA, Batool U, Shoorei H, Abdelnour SA, Ahmed JZ.Native breeds are essential for national stocks and genetic reservoir; therefore, the preservation of indigenous breeds is a key policy priority for countries around the world. Many conservationists would assert that genetic diversity is a prerequisite for adaptive evolution, and preserving genetic diversity will need conservation efforts for the long-term survival of domestic species. This study intended to evaluate the genetic diversity of the Iranian Kurdish horse population based on microsatellite indicators, which can partially prevent it from becoming extinct. Fifty-eight tail hair and b...
Cervantes I, Gutiérrez JP, García-Ballesteros S, Varona L.The racing time and rank at finish traits are commonly used for endurance horse breeding programs as a measure of their performance. Even so, given the nature of endurance competitions, many horses do not finish the race. However, the exclusion of non placed horses from the dataset could have an influence on the prediction of individual breeding values. The objective of the present paper was to develop a multitrait model including race time (T), rank (R) and placing (P), with different methodologies, to improve the genetic evaluation in endurance competitions in Spain. The database contained 6...
Hudson W.Egyptian Arabian horses have been maintained in a state of genetic isolation for over a hundred years. There is only limited genetic proof that the studbook records of female lines of Egyptian Arabian pedigrees are reliable. This study characterized the mitochondrial DNA (mtDNA) signatures of 126 horses representing 14 matrilines in the Egyptian Agricultural Organization (EAO) horse-breeding program. Results: Analysis of the whole D-loop sequence yielded additional information compared to hypervariable region-1 (HVR1) analysis alone, with 42 polymorphic sites representing ten haplotypes compar...
Park CS, Lee SY, Cho GJ.In this study, we aimed to investigate the recent changes such as allele frequencies and total probability of exclusion (PE) in Thoroughbred horses in Korea using short tandem repeat (STR) parentage panels between 2006 and 2016. Methods: The genotype was provided for 5,988 horse samples with 15 microsatellite markers (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG10, LEX3 and VHL20). Results: In our study, the observed number of alleles per locus ranged from 3 (HMS1) to 9 (ASB17) in 2006 and 4 (HMS1) to 9 (ASB2) in 2016, with a mean value of 6.28 and 6.40, respe...
Rushton J, Tichy A, Brem G, Druml T, Nell B.There are no studies on the ophthalmic health status in the Lipizzaner breed. Objective: To perform an ophthalmological survey in a closed herd in 3 housing systems. Methods: All horses at the Federal Stud Piber, Heldenberg and the Spanish Riding School Vienna were subjected to ophthalmological examination. Findings were documented and correlated with factors such as age, gender, location and housing situation. The interrelation of abnormalities of different regions was determined by calculating accuracy. Pedigree analysis of horses affected by cataract was performed. Results: A total of 267 h...
Putnová L, Štohl R, Vrtková I.We propose the first comprehensive in-depth study monitoring horses in the Czech Republic. We scanned 9,289 animals from 44 populations for 17 equine STRs. Other equids analysed involved Equus przewalskii and Equus asinus. The total of 228 different alleles were detected, with the mean number of 13.4 per locus. The highest allelic richness (AR) was found in the Welsh Part Bred (6.01), followed by the Camargue (5.93) and Czech Sport Pony (5.91), whereas the Friesian exhibited the lowest AR (3.06). Interpopulation differences explained approximately nine per cent of the total genetic diversity. ...
Ricard A, Dumont Saint Priest B, Danvy S, Barrey E.The aim of this study was to evaluate the genetic component of the locomotor jumping ability, via a wearable accelerometer sensor, and to estimate the genetic correlation with performance in competition, to introduce such criteria in selection schema. A sample of 1,056 young 3-year-old horses were equipped with a 3-dimensional accelerometer during a free jumping test, in regular breeding shows from 2015 to 2017. Seven variables were extracted from the dorso-ventral acceleration curve for the last three jumps over a double bar obstacle of 1.15 m for the front pole and 1.20 m for the back pole w...
Brault LS, Penedo MC.A putative mutation causative of cerebellar abiotrophy (CA), a genetic defect found almost exclusively in Arabian horses, was recently identified. Objective: To investigate the presence of the CA mutation in breeds other than Arabian and ascertain whether the mutation had been introduced into these breeds by Arabian ancestry. The CA mutation is present in breeds of horses with Arabian ancestry. Methods: Allele-specific PCR was used to genotype 1845 non-Arabian horses for the CA mutation. For those breeds in which at least one carrier was identified, an additional 266 horses were genotyped to d...
Myćka G, Klecel W, Stefaniuk-Szmukier M, Jaworska J, Musiał AD, Ropka-Molik K.The Polish draft horse (PDH) breed is a result of crossing local mares with imported cold-blooded stallions, such as Belgians, Ardennes, Fjords, and others. A part of the broodmare stock investigated in this study was also imported from various countries, such as Denmark. In this study, we investigate the genetic composition of the PDH by analyzing the whole mitochondrial d-loop variability and comparing it to previously demonstrated whole d-loop sequences of other cold-blooded breeds: Ardennais, Belgian, Breton, Clydesdale, Noriker, Norwegian Fjord, Percheron, and Suffolk. Our results show hi...
Jung YH, Han SH, Shin T, Oh MY.We determined the nucleotide sequences of the hypervariable D-loop region of mitochondrial DNA (mtDNA) from horse bone (humerus, A.D. 700 to A.D. 800) that was excavated from the Kwakji archaeological site, Jeju, Korea. We compared them with ones from extant horses. We designed three pairs of oligonucleotide primers from the tRNA-Thr and tRNA-Phe gene regions of mtDNA that are highly conserved among many other animal species. We cloned 232, 336, and 644 bp from the horse bone in order to determine the mtDNA D-loop sequence. The sequence was 1,124 bp long; the middle contained 19 tandem repeats...
Zimmermann E, Distl O.Before the genomics era, heritability estimates were performed using pedigree data. Data collection for pedigree analysis is time consuming and holds the risk of incorrect or incomplete data. With the availability of SNP-based arrays, heritability can now be estimated based on genotyping data. We used SNP array and 1.6 million imputed genotype data with different minor allele frequency restrictions to estimate heritabilities for osteochondrosis dissecans in the fetlock, hock and stifle joints of 446 Hanoverian warmblood horses. SNP-based heritabilities were estimated using a genomic restricted...
The Journal of heredityDecember 14, 2011
Volume 103, Issue 1 134-139 doi: 10.1093/jhered/esr121
Bigi D, Perrotta G.Catria is 1 of the 22 native Italian horse breeds that now survive from a larger number. Thirty individuals, representative of the Catria horse, were analyzed for 11 microsatellites and compared with data of 10 breeds reared in Italy. Three different approaches, genetic distances, correspondence analysis, and clustering methods, were considered to study genetic relationships among Catria and the other horse populations. Genetic differentiation among breeds was highly significant (P < 0.01) for all loci. Average F(ST) values indicate that around 10% of the total genetic variation was explain...
Goyache F, Alvarez I, Fernández I, Pérez-Pardal L, Royo LJ, Lorenzo L.Empirical evidence of the usefulness of different molecular-based methods to estimate the effective population size (N(e)) for conservation purposes in endangered livestock populations is reported. The black-coated Asturcón pony pedigree (1,981 individuals) was available. Additionally, a total of 267 Asturcón individuals born in 1998, 2002, and 2008 were typed for 15 microsatellites. These yearly cohorts (cohort(1998, 2002, 2008)) included almost all individuals kept for reproduction at the end of the corresponding foaling season. The genealogical realized N(e) was estimated for each cohort ...
Nolte W, Alkhoder H, Wobbe M, Stock KF, Kalm E, Vosgerau S, Krattenmacher N, Thaller G, Tetens J, Kühn C.In horses, parentage control is currently performed based on an internationally standardized panel of 17 microsatellite (MS) markers comprising 12 mandatory and five optional markers. Unlike MS, single nucleotide polymorphism (SNP) profiles support a wider portfolio of genomic applications, including parentage control. A transition to SNP-based parentage control is favorable, but requires additional efforts for ensuring generation-overlapping availability of marker genotypes of the same type. To avoid double genotyping of either parents or offspring for changing to SNP technology and enable ef...
Bolzon C, Joonè CJ, Schulman ML, Harper CK, Villagómez DA, King WA, Révay T.Disorders of sex development (DSD) have long been documented in domestic animal species including horses. However, there is only a single report of an androgen receptor (AR) mutation causative of such a DSD syndrome in a horse pedigree. Here, we present a new familial AR mutation in horses. A missense mutation (c.2042G>C) at AR exon 4 explains the segregation of the DSD in a Thoroughbred horse pedigree. The mutation, expected to affect the ligand-binding domain of the AR protein, led to complete androgen insensitivity of 64,XY SRY+, testicular DSD individuals. Additionally, the design of a ...
Campana MG, Whitten CM, Edwards CJ, Stock F, Murphy AM, Binns MM, Barker GW, Bower MA.Historic DNA data have the potential to identify phenotypic information otherwise invisible in the historical, archaeological and palaeontological record. In order to determine whether a single nucleotide polymorphism typing protocol based on single based extension (SNaPshot™) could produce reliable phenotypic data from historic samples, we genotyped three coat colour markers for a sample of historic Thoroughbred horses for which both phenotypic and correct genotypic information were known from pedigree information in the General Stud Book. Experimental results were consistent with the pedig...
Radovic L, Remer V, Krcal C, Rigler D, Brem G, Rayane A, Driss K, Benamar M, Machmoum M, Piro M, Krischke D, Butler-Wemken IV, Wallner B.In horses, demographic patterns are complex due to historical migrations and eventful breeding histories. Particularly puzzling is the ancestry of the North African horse, a founding horse breed, shaped by numerous influences throughout history. A genetic marker particularly suitable to investigate the paternal demographic history of populations is the non-recombining male-specific region of the Y chromosome (MSY). Using a recently established horse MSY haplotype (HT) topology and KASP™ genotyping, we illustrate MSY HT spectra of 119 Barb and Arab-Barb males, collected from the Maghreb regio...
Rahimi-Mianji G, Nejati-Javaremi A, Farhadi A.The present study was undertaken to genetically evaluate Turkmen horses for genetic diversity and to evaluate whether they have experienced any recent genetic bottlenecks. A total of 565 individuals from Turkmen horses were characterized for within breed diversity using 12 microsatellite markers. The estimated mean allelic diversity was (9.42 ± 1.78) per locus, with a total of 131 alleles in genotyped samples. A high level of genetic variability within this breed was observed in terms of high values of effective number of alleles (4.70 ± 1.36), observed heterozygosity (0.757 ± 0.19), expect...
Głażewska I, Gralak B, Naczk AM, Prusak B.Polish Arabian horses are one of the most important populations of this breed in the world. Their post-war history can be divided into two periods, with the dominant role of state studs until 1989, and the increasing significance of private breeding in the next years. The goal of the study was to evaluate genetic diversity and structure of the population under a new breeding policy. The analyses of breeding and microsatellite data from 1996 to 2012 provide a coherent picture of the population with constant flow of horses only in one direction from state to private studs. An increase in the num...
Swinburne JE, Hopkins A, Binns MM.The dominant grey coat colour gene of horses has been mapped using a whole genome scanning approach. Samples from a large half-sibling pedigree of Thoroughbred horses were utilized in order to map the grey coat colour locus, G. Multiplex groups of microsatellite markers were developed and used to efficiently screen the horse genome at a resolution of approximately 22 cM, based on an estimated map length for the horse genome of 2720 cM. The grey gene was assigned to chromosome 25 (ECA25), one of the smaller acrocentric horse chromosomes. Based on the current state of knowledge of conserved synt...
Kakoi H, Kikuchi M, Tozaki T, Hirota KI, Nagata SI.The integrity of thoroughbreds is maintained under strict regulation involving DNA parentage testing, which is robust in a population with high genetic variability. The genetic variability of the thoroughbred population is possibly fluctuating because of selective breeding that has focused on adaptations for racing performance. To monitor genetic variability within the population and the effectiveness of short tandem repeat (STR) parentage testing, we investigated allele frequencies and the exclusion probability (PE) of 16-17 loci of a parentage panel in the Japanese thoroughbred population ov...
Mari G, Castagnetti C, Rizzato G, Mislei B, Iacono E, Merlo B.Stallions are not selected for fertility but for other criteria (pedigree, conformation, performances, progeny), therefore valuable but subfertile stallions with poor semen quality are frequently used in commercial breeding programs. The object of this study was to evaluate whether sperm selection through a silane-coated silica colloid gradient centrifugation, with or without the addition of seminal plasma of a high fertile stallion, could improve the pregnancy rates of an oligospermic valuable stallion in a commercial breeding program. In 2008 breeding season (experiment 1, n=104 mares), simp...
Marín Navas C, Delgado Bermejo JV, McLean AK, León Jurado JM, Torres ARBYR, Navas González FJ.Genetic diversity and demographic parameters were computed to evaluate the historic effects of coat colour segregation in the process of configuration of the Hispano-Arabian horse (Há). Pedigree records from 207,100 individuals born between 1884 and 2019 were used. Although coat colour is not a determinant for the admission of Hispano-Arabian individuals as apt for breeding, it may provide a representative visual insight into the gene contribution of Spanish Purebred horses (PRE), given many of the dilution genes described in Há are not present in the Arabian Purebred breed (PRá). The lack ...
Pinard CL, Basrur PK.To characterize the ocular anomalies, determine their recurrence in families and assess the mode of inheritance of the most prevalent anomalies through pedigree analysis in a herd of Exmoor ponies. Methods: Thirty Exmoor ponies residing in south-western Ontario, Canada. Methods: Ophthalmic examination was performed using direct ophthalmoscopy, slit-lamp biomicroscopy and indirect ophthalmoscopy, pre- and post-pupillary dilation. Following compilation of ocular findings, pedigree analysis was conducted to assess the recurrence pattern of specific anomalies in families and the data were tested f...
