Genetic diversity in horses refers to the variation in genetic characteristics within and among populations of horses. This diversity is shaped by factors such as breeding practices, geographic distribution, and historical population dynamics. Genetic diversity is measured using various molecular markers and provides insights into the evolutionary history, population structure, and adaptability of horse breeds. It influences traits such as disease resistance, fertility, and performance. This page compiles peer-reviewed research studies and scholarly articles that explore the assessment, implications, and conservation of genetic diversity in equine populations.
Sohail Ashraf M, Basheer A, Iqbal F, Zahoor I.The current study aimed to evaluate the genetic diversity, level of admixture, and phylogenetic relationship, of the Pakistani horse breeds, along with their morphological characterization. Data for the body measurements showed that Morna horses had the highest values of body height, body length, chest girth, leg length, and head length, whereas the Baluchi horses had the lowest values for these traits. For the genetic diversity 64 animals, 15/breed except for Baluchi(14) and Topras(05), were genotyped by using the 17-plex equine genotyping kit. The AMOVA results showed that 13% of genetic div...
Tau RL, Ferreccio C, Bachir N, Torales F, Romera SA, Maidana SS.High-throughput sequencing of genomes has expanded our knowledge of the Alphaherpesvirinae, a widely extended subfamily of DNA viruses that recombine to increase their genetic diversity. It has been acknowledged that equid herpesvirus 1 (EHV-1) and equid herpesvirus 4 (EHV-4), two alphaherpesviruses with an economic impact on the horse industry, can recombine. This work aimed to analyze interspecific recombination between all equid alphaherpesvirus species, using genomes of EHV-1, EHV-3, EHV-4, EHV-6, EHV-8, and EHV-9 available in GenBank. 14 events of recombination by RDP4 and Simplot between...
Giontella A, Cardinali I, Sarti FM, Silvestrelli M, Lancioni H.Horse domestication and breed selection processes have profoundly influenced the development and transformation of human society and civilization over time. Therefore, their origin and history have always attracted much attention. In Italy, several local breeds have won prestigious awards thanks to their unique traits and socio-cultural peculiarities. Here, for the first time, we report the genetic variation of three loci of the male-specific region of the Y chromosome (MSY) of four local breeds and another one (Lipizzan, UNESCO) well-represented in the Italian Peninsula. The analysis also inc...
Machmoum M, Badaoui B, Petit D, Germot A, El Alaoui MA, Boujenane I, Piro M.Genetic diversity and phylogenetic relationships within the Arabian show horse populations are of particular interest to breeders worldwide. Using the complete mitochondrial DNA D-loop sequence (916 pb), this study aimed (i) to understand the genetic relationship between three populations, the Desert-Bred (DB), a subset of the Kingdom of Saudi Arabia (KSA), United Arab Emirates (UAE) and Bahrain (BAH), the Straight Egyptian (EG) and the Polish bloodline (PL), and (ii) to assess the accuracy of the traditional strain classification system based on maternal lines, as stated by the Bedouin cultur...
Spotin A, Dalir F, Hazratian T, Shekarchi AA, Mahami-Oskouei M, Farmani M, Dolatkhah A, Ahmadpour E.The genetic variability of apicomplexan parasite Babesia species is a principal strategy used by piroplasma to evade their hosts' immune responses. The purpose of this review was to evaluate our current knowledge on global haplotype distribution and phylogeography of Babesia ovis derived from sheep, goat, horse and ixodid (hard) ticks. Bibliographic English databases were searched from 2017 to 2023, identifying a total of 11 publications. The 18S ribosomal RNA (18S rRNA) sequences of B. ovis from Asia, Europe, and Africa were retrieved and subjected to estimate the genetic diversity and phylog...
An J, Tseveen K, Oyungerel B, Kong HS.Mongolian horses are one of the oldest horse breeds, and are very important livestock in Mongolia as they are used in various fields such as transportation, food (milk, meat), and horse racing. In addition, research and preservation on pure Mongolian breeds are being promoted under the implementation of the new Genetics of Livestock Resources' act in Mongolia. However, despite the implementation of this act, genetic research on Mongolian horses using microsatellites (MS) has not progressed enough. Therefore, this study was conducted to analyze the genetic polymorphism of five breeds (Gobi shan...
Kalantari M, Sharifiyazdi H, Ghaemi M, Ghane M, Nazifi S.In all equids worldwide, Theileria equi and Babesia caballi are believed to be two important erythrocytic protozoa that cause equine piroplasmosis. In addition, it was recently discovered that Theileria haneyi is another potential equine piroplasmosis (EP) agent. Ixodid ticks are the major vectors of these parasites. Equine piroplasmosis is of international importance and affects enormously the equine industry. In this study, for the first time, molecular prevalence and genetic diversity of piroplasma parasites (T. equi and B. caballi) in horses from Fars province (south of Iran) were determin...
Panigrahi M, Kumar H, Saravanan KA, Rajawat D, Sonejita Nayak S, Ghildiyal K, Kaisa K, Parida S, Bhushan B, Dutt T.Livestock plays a central role in sustaining human livelihood in South Asia. There are numerous and distinct livestock species in South Asian countries. Several of them have experienced genetic development in recent years due to the application of genomic technologies and effective breeding programs. This review discusses genomic studies on cattle, buffalo, sheep, goat, pig, horse, camel, yak, mithun, and poultry. The frontiers covered in this review are genetic diversity, admixture studies, selection signature research, QTL discovery, genome-wide association studies (GWAS), and genomic select...
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...
Kutara K, Ono T, Hisaeda K, Inoue Y, Henmi C, Sho K, Ohnishi A, Ohzawa E, Une Y, Iwata E, Shibano K, Asanuma T, Kitagawa H.Noma horses have the smallest body size among native Japanese horses and are classified as pony breeds by their size. Additionally, the Japanese horse breeds are classified into a single lineage, which includes Mongolian horses. Great intraspecific differences reportedly exist in the head shapes of domesticated horses, which have been investigated in various horse breeds. The present study aimed to evaluate the size of the nasal conchal bullae, and the paranasal sinuses of Noma horses in relation to the skull dimensions using computed tomography. Reconstructed images of the heads of five adult...
Luttman AM, Komine M, Thaiwong T, Carpenter T, Ewart SL, Kiupel M, Langohr IM, Venta PJ.Tetranucleotide and pentanucleotide short tandem repeat (hereafter termed tetraSTR and pentaSTR) polymorphisms have properties that make them desirable for DNA profiling and paternity testing. However, certain species, such as the horse, have far fewer tetraSTRs than other species and for this reason dinucleotide STRs (diSTRs) have become the standard for DNA profiling in horses, despite being less desirable for technical reasons. During our testing of a series of candidate genes as potentially underlying a heritable condition characterized by megaesophagus in the Friesian horse breed, we foun...
Yun J, Oyungerel B, Kong HS.This study aimed to identify the genetic diversity and population structure of Mongolian horse populations according to the province of residence (Khentii, KTP; Uvs, USP; Omnogovi and Dundgovi, GOP; Khovsgol, KGP) using 14 microsatellite (MS) markers. Methods: A total of 269 whole blood samples were obtained from the four populations (KTP, USP, GOP, KGP) geographically distinct provinces. Multiplex polymerase chain reaction (PCR) was conducted using 14 MS markers (AHT4, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, and VHL20), as recommended by the International So...
The Journal of heredityDecember 12, 2021
Volume 113, Issue 3 238-247 doi: 10.1093/jhered/esab070
Esdaile E, Avila F, Bellone RR.American Standardbreds were developed as a harness racing horse breed. The United States Trotting Association closed the studbook in 1973 and implemented a book size cap in 2009. This study aimed to investigate genetic diversity in the American Standardbred after the studbook cap was introduced using short tandem repeats (STRs) and single-nucleotide polymorphisms (SNPs). Sixteen STRs from horses foaled from 2010 to 2015 and their sires and dams (n = 50 621) were utilized to examine allelic richness (Ar), expected heterozygosity (HE), observed heterozygosity (HO), unbiased heterozygosity (HU), ...
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...
Kim SM, Yun SW, Cho GJ.The study aimed to evaluate the diversity of donkey populations by comparing with the diversity of Thoroughbred and Jeju Halla horses; identified breeding backgrounds can contribute to management and conservation of donkeys in South Korea. Methods: A total of 100 horse (50 Thoroughbreds and 50 Jeju Halla horses) and 79 donkeys samples were genotyped with 15 microsatellite markers (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG10, LEX3, and VHL20), to identify genetic diversity and relationships among horses and donkeys. Results: The observed number of alleles pe...
Próchniak T, Kasperek K, Knaga S, Rozempolska-Rucińska I, Batkowska J, Drabik K, Ziȩba G.The aim of the study was to characterize the population structure and assess the genetic diversity of warmblood horses used in the show jumping discipline. Pedigree data of 1,048 horses participating in the Polish Championships for Young Horses were analyzed. The pedigree of these animals included 12 863 individuals. The study consisted in analysis of the pedigree structure of the horses and characterization of the homozygosity and genetic diversity in the population. It was found that pedigree completeness and depth were sufficient for reliable assessment of the genetic diversity in the analy...
Fornal A, Kowalska K, Zabek T, Piestrzynska-Kajtoch A, Musiał AD, Ropka-Molik K.The aim of the conservation programme is to maintain the population size of endangered livestock breeds of less economic importance at a level that ensures the survival of the breed, the preservation of genetic diversity, and the preservation of as many pedigree lines as possible. The Polish Konik, a native Polish primitive-type horse breed and is one of the breeds included in such a programme in Poland. Presently, there are only 16 (of the 35 maternal lines known in 1962), some of which are endangered. We examined the genetic variability and structure of the Polish Konik maternal lines (176 i...
Liu S, Fu C, Yang Y, Zhang Y, Ma H, Xiong Z, Ling Y, Zhao C.To investigate the genetic diversity of Chinese indigenous horses and determine the genetic status of extant horse breeds, novel Y chromosomal microsatellite markers and known Y chromosomal SNPs and mtDNA loop sequences, were employed to study the genetic diversity levels of 13 Chinese indigenous horse populations and four introduced breeds. Sixteen Y-chromosomal microsatellite markers, including seven newly identified loci, were used in the genotyping. The results showed that 4 out of the 16 loci were highly polymorphic in Chinese indigenous horse populations, in which the polymorphisms of 3 ...
Marín Navas C, Delgado Bermejo JV, McLean AK, León Jurado JM, Torres ARBYR, Navas González FJ.Genetic diversity and population structure were analyzed using the historical and current pedigree information of the Arabian (PRá), Spanish Purebred (PRE), and Hispano-Arabian (Há) horse breeds. Genetic diversity parameters were computed and a canonical discriminant analysis was used to determine the contributions of ancestor breeds to the genetic diversity of the Há horse. Pedigree records were available for 207,100 animals born between 1884 and 2019. Nei's distances and the equivalent subpopulations number indicated the existence of a highly structured, integrated population for the Há ...
Cursino AE, Lima MT, Nogueira MF, de Aguiar DM, Franco Luiz APM, Alves PA, Araujo Junior JP, Kroon EG.The aetiological agent of equine infectious anaemia (EIA) is the retrovirus equine infectious anemia virus (EIAV) that infects all members of the Equidae family. The EIA is widely disseminated in the Brazilian territory with a high seroprevalence in the Brazilian Pantanal and is mainly diagnosed using agar gel immunodiffusion (AGID). There are few complete EIAV genome sequences available in GenBank, which had an impact on molecular detection studies. In this study, we conducted molecular detection and sequencing of EIAV proviral DNA from Brazilian horses. We analysed the genomic region from ex...
Fontanel M, Todd E, Drabbe A, Ropka-Molik K, Stefaniuk-Szmukier M, Myćka G, Velie BD.Arabian horses are not only one of the most ancient breeds in the world, but they are also one of the most appreciated racehorse breeds today. The breed generates attention for their phenomenal endurance ability and their capability for gallop racing. Consequently, genetic testing to select the best individuals is attracting ever increasing interests from the Arabian industry. As such, the aim of this study was to further investigate associations between performance and variation at candidate genes suspected of having a key role in Arabian gallop racing performance. Generalized linear models w...
Machmoum M, Boujenane I, Azelhak R, Badaoui B, Petit D, Piro M.Understanding the genetic diversity and the relationships among the show Arabian horse populations is a current issue for breeders and professionals. This study aimed to define the relationship among the Desert breed, the Straight Egyptian, and the Polish Arabian populations by considering the historical background of their origin and to verify their genetic diversity. All selected samples were related to Arabian show activities. One hundred forty four hair samples were collected from horses at stud farms having notoriety in the breeding of Arabians from different geographic regions. A set of ...
Dubey JP, Murata FHA, Cerqueira-Cézar CK, Kwok OCH.Toxoplasma gondii infections are common in humans and animals worldwide. The present review summarizes worldwide information on the prevalence of clinical and subclinical infections, epidemiology, and genetic diversity of T. gondii in horses, donkeys and other equids in the past decade. This review will be of interest to biologists, parasitologists, veterinarians, and public health workers.
Santagostino M, Piras FM, Cappelletti E, Del Giudice S, Semino O, Nergadze SG, Giulotto E.Interstitial telomeric sequences (ITSs) are short stretches of telomeric-like repeats (TTAGGG)n at nonterminal chromosomal sites. We previously demonstrated that, in the genomes of primates and rodents, ITSs were inserted during the repair of DNA double-strand breaks. These conclusions were derived from sequence comparisons of ITS-containing loci and ITS-less orthologous loci in different species. To our knowledge, insertion polymorphism of ITSs, i.e., the presence of an ITS-containing allele and an ITS-less allele in the same species, has not been described. In this work, we carried out a gen...
McGivney BA, Han H, Corduff LR, Katz LM, Tozaki T, MacHugh DE, Hill EW.The Thoroughbred horse is a highly valued domestic animal population under strong selection for athletic phenotypes. Here we present a high resolution genomics-based analysis of inbreeding in the population that may form the basis for evidence-based discussion amid concerns in the breeding industry over the increasing use of small numbers of popular sire lines, which may accelerate a loss of genetic diversity. In the most comprehensive globally representative sample of Thoroughbreds to-date (n = 10,118), including prominent stallions (n = 305) from the major bloodstock regions of the w...
Cook SJ, Li G, Zheng Y, Willand ZA, Issel CJ, Cook RF.Although the equine lentivirus (equine infectious anemia virus [EIAV]) poses a major threat to equid populations throughout most regions of the world, detailed knowledge concerning its molecular epidemiology is still in its infancy. Such information is important because the few studies conducted to date suggest there is extensive genetic variation between viral isolates that if confirmed has significant implications for future vaccine design and development of newer diagnostic procedures. Here, we avoid potential assembly artifacts inherent in composite sequencing techniques by using long-rang...
Deshiere A, Berthet N, Lecouturier F, Gaudaire D, Hans A.Equine infectious anemia virus (EIAV) is responsible of acute disease episodes characterized by fever, anemia, thrombocytopenia and anorexia in equids. The high mutation rate in EIAV genome limited the number of full genome sequences availability. In the present study, we used the SureSelect target enrichment system with Illumina Next Generation Sequencing to characterize the proviral DNA of Equine Infectious Anemia Virus (EIAV) from asymptomatic horses. This approach allows a direct sequencing of the EIAV whole genome without cloning or amplification steps and we could obtain for the first ti...
Jeong MJ, Jeong BH.Prion diseases are fatal neurodegenerative diseases characterised by the accumulation of an abnormal prion protein isoform (PrP), which is converted from the normal prion protein (PrP). Prion diseases have been reported in an extensive number of species but not in horses up to now; therefore, horses are known to be a species resistant to prion diseases. The prion-like protein gene () is closely located downstream of the prion protein gene () and the prion-like protein (Doppel) is a homologue with PrP. Previous studies have shown that an association between prion diseases and polymorphisms of t...
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...
Kashi Y, Tikochinsky Y, Genislav E, Iraqi F, Nave A, Beckmann JS, Gruenbaum Y, Soller M.Southern blots of genomic DNA from a variety of species digested by restriction endonucleases having a four-bp specificity, were probed with a bovine genomic clone consisting of seven tandem poly-TG stretches separated by a 29bp linker sequence. Highly variable DNA 'fingerprint' patterns were obtained in chicken, sheep, and horse, moderately variable DNA 'fingerprints' in mouse and man, and a monomorphic pattern in Drosophila. In chicken, horse and man a (TG)10 synthetic oligonucleotide probe gave results identical to those given by the bovine probe. Furthermore, in chicken the DNA fingerprint...
van Grevenhof EM, Schurink A, Ducro BJ, van Weeren PR, van Tartwijk JM, Bijma P, van Arendonk JA.Osteochondrosis (OC) is an important orthopedic developmental disorder in many horse populations. A review of the literature revealed widely variable heritability estimates for the disorder. We estimated the genetic variables (heritabilities and genetic correlations) of various manifestations of OC. Femoropatellar, tarsocrural, and metacarpophalangeal and metatarsophalangeal joints of 811 randomly selected yearlings from the Royal Warmblood Studbook of The Netherlands, descending from 32 representative stallions, were scored for OC at 28 predilection sites. At each site, OC was scored in 5 cat...
Senju N, Tozaki T, Kakoi H, Almunia J, Maeda M, Matsuyama R, Takasu M.To help plan conservation of the endangered Miyako horse, a biological resource of the Miyako Islands in Japan, we characterized the genetics of the breed by genotyping 32 microsatellites and identifying mitochondrial DNA haplotypes. We also calculated genetic distances between individuals based on the proportion of shared alleles and visualized the genetic relationships with a phylogenetic tree. Two important results were obtained. One is that accurate pedigree registration of the horse by using microsatellites is possible, as the exclusion power of parentage testing is 0.999998. Another is t...
Prystupa JM, Juras R, Cothran EG, Buchanan FC, Plante Y.As part of the requirements of the Convention on Biological Diversity, Canada has been investigating the genetic diversity of its native equine and pony populations. Along with examining four indigenous Canadian equine populations (Canadian horse, Lac La Croix pony, Newfoundland pony and Sable Island population), another 10 Mountain and Moorland, three Nordic, four horse and two feral equine populations (thought to have influenced some pony breeds) were also investigated. In total, 821 individuals were genotyped at 38 microsatellite loci. Results of the analysis of molecular variance indicated...
Malik P, Bálint A, Dán A, Pálfi V.Equine herpesvirus-1 (EHV-1) can be classified into distinct groups by single nucleotide polymorphisms (SNPs) in their genomes. Only a few of these can be associated with a special attribute of the virus. Differences in the ORF30 region can determine the neuropathogenic potential, while by substitutions in the ORF68 region several strain groups can be made. In previous studies no connection was found between the neuropathogenic potential and the SNPs in ORF68, but the occurrence of members of distinct groups in different outbreaks can facilitate epidemiological investigations because the geogr...
Binns MM, Boehler DA, Bailey E, Lear TL, Cardwell JM, Lambert DH.Changes in the inbreeding coefficient, F, in the Thoroughbred horse over the past 45 years have been investigated by genotyping 467 Thoroughbred horses (born between 1961 and 2006) using the Illumina Equine SNP50 bead chip, which comprises 54,602 SNPs uniformly distributed across the equine genome. The Spearman rank correlation coefficient, r, between the year of birth and F was estimated. The results indicate that inbreeding in Thoroughbreds has increased over the past 40 years, with r = 0.24, P < 0.001 demonstrating that there is a highly significant, though relatively weak correlation be...
Stadejek T, Mittelholzer Ch, Oleksiewicz MB, Paweska J, Belák S.Equine arteritis virus (EAV) was detected by RT-nested PCR in semen samples from a naturally infected South African donkey. Sequence analysis of the amplified ORF5 fragment revealed only 60 to 70% nucleotide identity to a panel of EAV reference sequences. The unique donkey EAV sequence was also found to be stable during passage in horses. The sequence data reported in this study indicate that the South African donkey variant might represent a new genotype of EAV. The distinct genetic properties of the South African asinine strain of EAV suggest a divergent evolution of this arterivirus in vari...
Yang YH, Kim KI, Cothran EG, Flannery AR.We used sequence polymorphism of the mitochondrial DNA D-loop (968 bp excluding the tandem repeat region) to determine genetic diversity of horses inhabiting Cheju (a southern island of Korea). Seventeen haplotypes with frequencies from 1.5 to 21.5% were found among 65 Cheju horse samples. Genetic diversity (h) of the 17 haplotypes was calculated to be 0.91, indicating that the extant Cheju horse population consists of diverse genetic groups in their maternal lineage. Phylogenetic analysis showed that 17 types of Cheju (D-loop sequences determined), 5 Mongolian, 6 Arabian, 3 Belgian, 2 Tsushim...
Dugat T, Zanella G, Véran L, Lesage C, Girault G, Durand B, Lagrée AC, Boulouis HJ, Haddad N.Anaplasma phagocytophilum is the causative agent of tick-borne fever, a disease with high economic impact for domestic ruminants in Europe. Epidemiological cycles of this species are complex, and involve different ecotypes circulating in various host species. To date, these epidemiological cycles are poorly understood, especially in Europe, as European reservoir hosts (i.e. vertebrate hosts enabling long-term maintenance of the bacterium in the ecosystem), of the bacterium have not yet been clearly identified. In this study, our objective was to explore the presence, the prevalence, and the ge...
Fornal A, Kowalska K, Zabek T, Piestrzynska-Kajtoch A, Musiał AD, Ropka-Molik K.The aim of the conservation programme is to maintain the population size of endangered livestock breeds of less economic importance at a level that ensures the survival of the breed, the preservation of genetic diversity, and the preservation of as many pedigree lines as possible. The Polish Konik, a native Polish primitive-type horse breed and is one of the breeds included in such a programme in Poland. Presently, there are only 16 (of the 35 maternal lines known in 1962), some of which are endangered. We examined the genetic variability and structure of the Polish Konik maternal lines (176 i...
Machmoum M, Boujenane I, Azelhak R, Badaoui B, Petit D, Piro M.Understanding the genetic diversity and the relationships among the show Arabian horse populations is a current issue for breeders and professionals. This study aimed to define the relationship among the Desert breed, the Straight Egyptian, and the Polish Arabian populations by considering the historical background of their origin and to verify their genetic diversity. All selected samples were related to Arabian show activities. One hundred forty four hair samples were collected from horses at stud farms having notoriety in the breeding of Arabians from different geographic regions. A set of ...
May FJ, Clark DC, Pham K, Diviney SM, Williams DT, Field EJ, Kuno G, Chang GJ, Cheah WY, Setoh YX, Prow NA, Hobson-Peters J, Hall RA.The Kokobera virus group comprises mosquito-borne flaviviruses that cluster together phylogenetically. These viruses are unique to Australia and Papua New Guinea, and have been associated with a mild polyarticular disease in humans. Recent isolation of genetically diverse viruses within this group has prompted analysis of their genetic and phenotypic relationships. Phylogenetic analysis based on complete ORF, the envelope gene or the NS5/3' untranslated region supported the separation of the group into distinct species: Kokobera virus (KOKV), Stratford virus, New Mapoon virus, MK7979 and TS527...
Druml T, Baumung R, Sölkner J.The pedigree of the current Austrian Noriker draught horse population comprising 2808 horses was traced back to the animals considered as founders of this breed. In total, the number of founders was 1991, the maximum pedigree length was 31 generations, with an average of 12.3 complete generations. Population structure in this autochthonous Austrian draught horse breed is defined by seven breeding regions (Carinthia, Lower Austria, Salzburg, Styria, Tyrol, Upper Austria and Vorarlberg) or through six coat colour groups (Bay, Black, Chestnut, Roan, Leopard, Tobiano). Average inbreeding coefficie...
Liu S, Fu C, Yang Y, Zhang Y, Ma H, Xiong Z, Ling Y, Zhao C.To investigate the genetic diversity of Chinese indigenous horses and determine the genetic status of extant horse breeds, novel Y chromosomal microsatellite markers and known Y chromosomal SNPs and mtDNA loop sequences, were employed to study the genetic diversity levels of 13 Chinese indigenous horse populations and four introduced breeds. Sixteen Y-chromosomal microsatellite markers, including seven newly identified loci, were used in the genotyping. The results showed that 4 out of the 16 loci were highly polymorphic in Chinese indigenous horse populations, in which the polymorphisms of 3 ...
Deshiere A, Berthet N, Lecouturier F, Gaudaire D, Hans A.Equine infectious anemia virus (EIAV) is responsible of acute disease episodes characterized by fever, anemia, thrombocytopenia and anorexia in equids. The high mutation rate in EIAV genome limited the number of full genome sequences availability. In the present study, we used the SureSelect target enrichment system with Illumina Next Generation Sequencing to characterize the proviral DNA of Equine Infectious Anemia Virus (EIAV) from asymptomatic horses. This approach allows a direct sequencing of the EIAV whole genome without cloning or amplification steps and we could obtain for the first ti...
Choi SK, Cho CY, Yeon SH, Cho BW, Cho GJ.Genetic characterization of the Jeju horse (JH) was performed to construct a correct pedigree of the JH family. A total of 111 horses including 79 JH were genotyped using 20 microsatellite loci. The number of alleles varied from 5 to 11 (mean 7.45) in the JH. The observed heterozygosity and expected heterozygosity ranged from 0.293 to 0.891 and from 0.357 to 0.841, respectively. The polymorphic information contents (PIC) ranged from 0.335 to 0.816. AHT4, ASB2, ASB17, ASB23, CA425, HMS2, HMS3, HTG10, LEX3 and VHL20 loci had relatively high PIC values (> 0.7). The total exclusion probability ...
Rendo F, Iriondo M, Manzano C, Estonba A.Here, we present the results of a genetic analysis of 463 Pottoka ponies corresponding to four generations, using 17 microsatellite markers. Ten years after the beginning of the Pottoka conservation programme, the values for the genetic diversity of the breed are still high and stable, indicating the success of the programme. We found null alleles in Pottoka for the ASB23, HMS3 and HTG10 microsatellites. Together with information obtained from other pony breeds from the Iberian Peninsula, this finding indicates that these microsatellites should not be used for phylogenetic analyses or parentag...
Kim SM, Yun SW, Cho GJ.The study aimed to evaluate the diversity of donkey populations by comparing with the diversity of Thoroughbred and Jeju Halla horses; identified breeding backgrounds can contribute to management and conservation of donkeys in South Korea. Methods: A total of 100 horse (50 Thoroughbreds and 50 Jeju Halla horses) and 79 donkeys samples were genotyped with 15 microsatellite markers (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG10, LEX3, and VHL20), to identify genetic diversity and relationships among horses and donkeys. Results: The observed number of alleles pe...
Cothran EG, MacCluer JW, Weitkamp LR, Bailey E.American Standardbred horses are divided into two groups based upon gait: the trot and the pace. The tendency to trot (diagonally opposite legs moving forward together) or pace (the two legs on the same side of the body moving forward together) appears to be genetically determined, although no formal genetic analysis has been undertaken. There is nearly complete assortative mating for gait; however, about 20% of the offspring sired by trotters are registered as pacers, while fewer than 1% of those sired by pacers are registered as trotters. Electrophoretically detectable genic variation at 13 ...
Thirstrup JP, Pertoldi C, Loeschcke V.A genetic analysis was performed on three indigenous Danish horse breeds using 12 microsatellite markers from a standard kit for parental testing. These three breeds are all considered endangered based on their small population sizes. Genetic variation in these three breeds was comparable to other horse breeds in Europe, and they do not seem to be at immediate danger of extinction caused by genetic deterioration. The Knabstrupper breed had more genetic variation, as measured by expected heterozygosity and allelic richness, than the other two breeds (Frederiksborg and Jutland). F(ST) statistics...
Bogumil R, Hunter CL, Maurus R, Tang HL, Lee H, Lloyd E, Brayer GD, Smith M, Mauk AG.The interaction of azide with variants of horse heart myoglobin (Mb) has been characterized by Fourier transform infrared (FTIR), electron paramagnetic resonance (EPR), and UV-VIS absorption spectroscopy and by molecular modeling calculations. Distal histidine variants (His64Thr, His64Ile, His64Lys) and charged surface variants (Val67Arg, Lys45Glu, Lys45Glu/Lys63Glu) were included in this study. All variants, with the exception of Val67Arg, have a lower azide affinity than the wild-type protein. Analysis of the temperature dependence of the FTIR spectra (277-313 K) revealed that the wild-type ...
Nagarajan MM, Simard C.Gag genetic heterogeneity of equine infectious anemia virus (EIAV) variants in naturally infected horses in Canada was studied since very limited information is available on the variability of EIAV Gag sequences in public database. A phylogenetic analysis based on 414nts of Gag gene sequences amplified by a nested polymerase chain reaction (PCR) revealed the distinct divergence of these variants compared to other published strains in a corresponding region. Significant predicted amino acid sequence variations were also identified in an immunorelevant region within this fragment which correspon...
Ianella P, Albuquerque MSM, Paiva SR, Egito AA, Almeida LD, Sereno FTPS, Carvalho LFR, Mariante AS, McManus CM.The first horses were brought to Brazil by the colonizers after 1534. Over the centuries, these animals evolved and adapted to local environmental conditions usually unsuitable for exotic breeds, thereby originating locally adapted Brazilian breeds. The present work represents the first description of maternal genetic diversity in these horse breeds based on D-loop sequences. A D-Loop HSV-I fragment of 252 bp, from 141 horses belonging to ten Brazilian breeds / genetic groups (locally adapted and specialized breeds) were analysed. Thirty-five different haplotypes belonging to 18 haplogroups we...
Zeng L, Chen N, Yao Y, Dang R, Chen H, Lei C.To determine the genetic diversity and validate the pedigree record of Chinese Guanzhong horse, 67 individuals were genotyped with eight microsatellite markers. In our study, the mean observed and expected heterozygosities were 0.51 and 0.66, respectively. The mean observed number of alleles for the Guanzhong horse was 3.88. Nonetheless, the total value of F multiloci clearly indicates that about 0.5% of overall genetic variation is due to line founder differences, while differences among individuals are responsible for the remaining 99.5%. In addition, the polymorphic information content (PIC...
Feral horses in Theodore Roosevelt National Park (TRNP) represent an iconic era of the North Dakota Badlands. Their uncertain history raises management questions regarding origins, genetic diversity, and long-term genetic viability. Hair samples with follicles were collected from 196 horses in the Park and used to sequence the control region of mitochondrial DNA (mtDNA) and to profile 12 autosomal short tandem repeat (STR) markers. Three mtDNA haplotypes found in the TRNP horses belonged to haplogroups L and B. The control region variation was low with haplotype diversity of 0.5271, nucleotide...
Zuccaro A, Bordonaro S, Criscione A, Guastella AM, Perrotta G, Blasi M, D'Urso G, Marletta D.Sanfratellano is a native Sicilian horse breed, mainly reared in the north east of the Island, developed in the 19th century from local dams and sires with a restricted introgression of Oriental, African and, more recently, Maremmano stallions. In this study, the genetic relationships and admixture among Sanfratellano, the other two Sicilian autochthonous breeds and Maremmano breed were assessed using a set of microsatellites. The main goals were to infer the impact of Maremmano breed in the current Sanfratellano horse and to provide genetic information useful to improve the selection strategi...
Jeong MJ, Jeong BH.Prion diseases are fatal neurodegenerative diseases characterised by the accumulation of an abnormal prion protein isoform (PrP), which is converted from the normal prion protein (PrP). Prion diseases have been reported in an extensive number of species but not in horses up to now; therefore, horses are known to be a species resistant to prion diseases. The prion-like protein gene () is closely located downstream of the prion protein gene () and the prion-like protein (Doppel) is a homologue with PrP. Previous studies have shown that an association between prion diseases and polymorphisms of t...
Otgonsuren D, Amgalanbaatar T, Narantsatsral S, Enkhtaivan B, Munkhgerel D, Zoljargal M, Davkharbayar B, Myagmarsuren P, Battur B, Battsetseg B....Equine piroplasmosis is a tick-borne disease caused by Theileria equi and Babesia caballi in horses. Because of its impact on horse industry, control of this disease is crucial for endemic countries. The control of equine piroplasmosis may be influenced by the genotypic diversity of T. equi and B. caballi. Mongolia, a country with a thriving livestock industry, is endemic for T. equi and B. caballi. However, nationwide epidemiological surveys have not been conducted to determine the current status of infections and genetic diversity of these two parasite species. Therefore, the objective of th...
Sigurðardóttir H, Ablondi M, Kristjansson T, Lindgren G, Eriksson S.The Icelandic horse and Exmoor pony are ancient, native breeds, adapted to harsh environmental conditions and they have both undergone severe historic bottlenecks. However, in modern days, the selection pressures on these breeds differ substantially. The aim of this study was to assess genetic diversity in both breeds through expected (HE) and observed heterozygosity (HO) and effective population size (Ne). Furthermore, we aimed to identify runs of homozygosity (ROH) to estimate and compare genomic inbreeding and signatures of selection in the breeds. Results: HO was estimated at 0.34 and 0.33...
