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.
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...
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...
Giacomoni EH, Fernández-Stolz GP, Freitas TR.The genetic variability for a sample of 227 animals from three populations of Pantaneiro horses was estimated using data from 10 microsatellite loci. The number of alleles and the proportion of heterozygosity indicated high variability. A total of 91 alleles were found, with a significantly high mean number of alleles. The mean polymorphic information content was 0.7 and the paternity exclusion probability was 99.3%. The inbreeding coefficient (F(IS)) was low for the three populations: Ipiranga (F(IS) = 0.147), Nova Esperança (F(IS) = 0.094) and Promissão (F(IS) = 0.108). Genetic differentia...
Dugarjaviin M, Yang H.Mongolian horse is a kind of important breed resource of local horses in our country. It has a lot of advantages such as powerful endurance, rough feeding resistance, and strong disease resistance. These advantages have become driving force for in-depth study on Mongolian horse. Genetic diversity can reflect all the genetic information of a species or a variety, namely, it reflects the richness of genetic diversity and confirms the degree of uniqueness of genetic resources through genetic markers. This paper introduces the progress in the study on genetic diversity of Mongolian horse in many a...
Hamann H, Distl O.A data set constituting a total of 310,109 Hanoverian warmblood horses was analyzed to ascertain the genetic variability, coefficients of inbreeding, and gene contributions of foreign populations. The reference population contained all Hanoverian horses born from 1980 to 2000. In addition, Hanoverian stallions born from 1980 to 1995 and Hanoverian breeding mares from the birth years 1980 to 1995 with registered foals were analyzed for the same genetic parameters. The average complete generation equivalent was approximately 8.43 for the reference population. The mean coefficient of inbreeding w...
Liu L, Castillo-Olivares J, Davis-Poynter NJ, Baule C, Xia H, Belák S.Samples from horses experimentally infected with the "large plaque variant (LP3A+)" of equine arteritis virus were analysed. These included 182 nasal swabs collected from day 1 to 14 post-infection (p.i.), and 21 virus isolates obtained from white blood cells of animals that showed a prolonged viraemia between days 30 to 72 p.i. In order to determine the genetic stability of the virus and particularly to characterise the genetic variants found during the prolonged viraemia, partial sequences of open reading frame 5 (ORF5) encoding glycoprotein 5 (GP5) were generated. Viruses with amino acid su...
The Journal of hereditySeptember 13, 2007
Volume 98, Issue 6 594-602 doi: 10.1093/jhered/esm064
Plante Y, Vega-Pla JL, Lucas Z, Colling D, de March B, Buchanan F.The present-day Sable Island horse population, inhabiting an island off the eastern coast of Canada, is believed to have originated mainly from horses confiscated from the early French settlers in Nova Scotia in the latter half of the 18th century. In 1960, the Sable Island horses were given legal protected status and no human interference has since been allowed. The objective of this study was to characterize the current genetic diversity in Sable Island horses in comparison to 15 other horse breeds commonly found in Canada and 5 Spanish breeds. A total of 145 alleles from 12 microsatellite l...
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...
Zhang J, Miszczak F, Pronost S, Fortier C, Balasuriya UB, Zientara S, Fortier G, Timoney PJ.Genetic variation and phylogenetic relationships among 22 French isolates of equine arteritis virus (EAV) obtained over four breeding seasons (2001-2004) were determined by sequencing open reading frames (ORFs) 2a-7. The ORFs 2a-7 of 22 isolates differed from the prototype virulent Bucyrus strain of EAV by between 14 (99.5% identity) and 328 (88.7% identity) nucleotides, and differed from each other by between 0 (100% identity) and 346 (88.1% identity) nucleotides, confirming genetic diversity among EAV strains circulating in France. Phylogenetic analysis based on the partial ORF5 sequences (n...
Amirinia C, Seyedabadi H, Banabazi MH, Kamali MA.Genetic diversity within the Iranian Caspian horse was evaluated using 8 different microsatellite pairs on 45 Caspian horse blood samples. This molecular characterisation was undertaken to evaluate the problem of genetic bottlenecks, if any, in this breed. The number of alleles per locus varied from 3 to 5 with mean value of 4.125. All markers have relatively high PIC value (> 0.6), observed heterozygosity; 0.9433, expected Levene's heterozygosity 0.6856 and expected Nei's heterozygosity equal to 0.6762. This study indicated the existence of substantial genetic diversity in the Caspian hors...
Sponseller BA, Sparks WO, Wannemuehler Y, Li Y, Antons AK, Oaks JL, Carpenter S.The principal neutralizing domain (PND) of equine infectious anemia virus (EIAV) is located in the V3 region of SU. Genetic variation in the PND is considered to play an important role in immune escape and EIAV persistence; however, few studies have characterized genetic variation in SU during the inapparent stage of disease. To better understand the mechanisms of virus persistence, we undertook a longitudinal study of SU variation in a pony experimentally inoculated with the virulent EIAV(Wyo). Viral RNA isolated from the inoculum and from sequential sera samples was amplified by RT-PCR, clon...
Kakoi H, Tozaki T, Gawahara H.To assess the genetic diversity of Japanese native horse populations, we examined seven such populations using mitochondrial DNA (mtDNA) and microsatellite analyses. Four reference populations of Mongolian horses and European breeds were employed as other equids. In the mtDNA analysis, the control region (D-loop) of 411 bp was sequenced, and 12 haplotypes with 33 variable sites were identified in the Japanese native horses. The phylogenetic tree constructed by haplogrouping and using worldwide geographic references indicated that the haplotypes of the Japanese native horses were derived from s...
Luís C, Juras R, Oom MM, Cothran EG.There are three native Portuguese horse breeds: Lusitano, Sorraia and Garrano. This study compares diversity patterns of 17 protein and 12 microsatellite markers in these three as well as 30 other breeds to infer relationships among the breeds and to compare levels of polymorphism of these breeds for use in conservation efforts. The Garrano and the Lusitano showed a high level of genetic diversity, similar to that observed for most of the other analysed breeds, while the Sorraia and Friesian breeds showed low levels of variation for both genetic marker types. The combined protein and microsate...
Iwańczyk E, Juras R, Cholewiński G, Cothran EG.In this study a wide range of genetic markers (12 microsatellites, 7 blood-group loci, 10 blood-protein loci) and mitochondrial DNA (mtDNA) were used to assess genetic diversity in Polish Heavy horses. Three random samples were sequenced for 421 bp of the mitochondrial D-loop region, but no clear phylogenetic patterns were seen in mtDNA variation. Both heterozygosity and diversity levels are fairly high in Polish Heavy horses. In phylogenetic analysis the draught horses form a distinct cluster that pairs with the true pony breeds. Within this 'cold-blooded' group, the Polish Heavy Horse cluste...
Marletta D, Tupac-Yupanqui I, Bordonaro S, García D, Guastella AM, Criscione A, Cañón J, Dunner S.The distribution of genetic diversity and the genetic relationships among western Mediterranean horse breeds were investigated using microsatellite markers. The examined sample included seven Spanish and three Italian local horse breeds and populations, plus a Spanish Thoroughbred outgroup. The total number of animals examined was 682 (on average 62 animals per breed; range 20-122). The microsatellite marker set analysed provided 128 alleles (10.7 alleles per locus). Within-breed genetic diversity was always high (>0.70), with breeds contributing about 8% of the total genetic variability. T...
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...
Wolc A, Bresińska A, Szwaczkowski T.Twinning is a serious problem in Thoroughbred horses, as most of the multiple pregnancies are miscarried and live foals present lower performance values. The aim of this study was to estimate the heritability and repeatability of twinning in Thoroughbred horses. A total of 12648 pregnancies of 2033 Thoroughbred mares born between 1929 and 1994 in 11 studs were included. The analysis was performed by the use of AI-REML algorithm under three threshold animal models. The first model included effects of stud, mare's birth period and interaction between them as fixed. The second model included the ...
Zabek T, Nogaj A, Radko A, Nogaj J, Słota E.Genetic variation of endangered Biłgoraj horses and two common Polish horse breeds was compared with the use of 12 microsatellite loci (AHT4, AHT5, ASB2, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10, VHL20). Lower allelic diversity was detected in all investigated populations in comparison to other studies. Large differences in the frequencies of microsatellite alleles between Biłgoraj horses and two other horse breeds were discovered. In all polymorphic loci all investigated breeds were in the Hardy-Weinberg equilibrium. Mean Fis values and the results of a test for the presence of a rec...
Tandon R, Lyons ET, Tolliver SC, Kaplan RM.Cyathostomins are among the most important intestinal nematodes of horses, yet, the literature on the molecular genetics of these worms is scarce. In this study, the technique of amplified fragment length polymorphism (AFLP) was applied to study the genetic diversity as well as to determine the effect of moxidectin selection on the population genetic diversity for Cylicocyclus nassatus, one of the most common cyathostomin species. Genomic DNAs from 30 individual male worms were used from each of two populations: an avermectin-milbemycin (AM)-naive population (Population-S) and a population der...
de la Fuente J, Massung RF, Wong SJ, Chu FK, Lutz H, Meli M, von Loewenich FD, Grzeszczuk A, Torina A, Caracappa S, Mangold AJ, Naranjo V, Stuen S....The causative agent of human granulocytic ehrlichiosis was recently reclassified as Anaplasma phagocytophilum, unifying previously described bacteria that cause disease in humans, horses, dogs, and ruminants. For the characterization of genetic heterogeneity in this species, the homologue of Anaplasma marginale major surface protein 4 gene (msp4) was identified, and the coding region was PCR amplified and sequenced from a variety of sources, including 50 samples from the United States, Germany, Poland, Norway, Italy, and Switzerland and 4 samples of A. phagocytophilum-like organisms obtained f...
Sátková-Jakabová D, Trandzík J, Hudecová-Kvasnáková L, Hegedüsová-Zetochová E, Bugarský A, Buleca J, Zöldág L, Jakab F, Fl'ak P.Genetic variation at six microsatellite loci was analysed for five Thoroughbred subpopulations to determine the magnitude of genetic differentiation and the genetic relationships among the subpopulations. Significant deviations from Hardy-Weinberg equilibrium were shown for a number of locus-population combinations, with all subpopulations. The genetic diversities and relationships of five Thoroughbred subpopulations were evaluated using six microsatellites recommended by the International Society of Animal Genetics (ISAG). The allele frequencies, the effective numbers of alleles, and the obse...
Aberle KS, Hamann H, Drögemüller C, Distl O.We compared the genetic diversity and distance among six German draught horse breeds to wild (Przewalski's Horse), primitive (Icelandic Horse, Sorraia Horse, Exmoor Pony) or riding horse breeds (Hanoverian Warmblood, Arabian) by means of genotypic information from 30 microsatellite loci. The draught horse breeds included the South German Coldblood, Rhenish German Draught Horse, Mecklenburg Coldblood, Saxon Thuringa Coldblood, Black Forest Horse and Schleswig Draught Horse. Despite large differences in population sizes, the average observed heterozygosity (H(o)) differed little among the heavy ...
Bowling AT, Zimmermann W, Ryder O, Penado C, Peto S, Chemnick L, Yasinetskaya N, Zharkikh T.In our continuing efforts to document genetic diversity in Przewalski's horses and relatedness with domestic horses, we report genetic variation at 22 loci of blood group and protein polymorphisms and 29 loci of DNA (microsatellite) polymorphisms. The loci have been assigned by linkage or synteny mapping to 20 autosomes and the X chromosome of the domestic horse (plus four loci unassigned to a chromosome). With cumulative data from tests of 568 Przewalski's horses using blood, hair or tooth samples, no species-defining markers were identified, however a few markers were present in the wild spe...
The Journal of heredityOctober 15, 2003
Volume 94, Issue 5 374-380 doi: 10.1093/jhered/esg079
Tozaki T, Takezaki N, Hasegawa T, Ishida N, Kurosawa M, Tomita M, Saitou N, Mukoyama H.The genetic relationships of seven Japanese and four mainland-Asian horse populations, as well as two European horse populations, were estimated using data for 20 microsatellite loci. Mongolian horses showed the highest average heterozygosities (0.75-0.77) in all populations. Phylogenetic analysis showed the existence of three distinct clusters supported by high bootstrap values: the European cluster (Anglo-Arab and thoroughbreds), the Hokkaido-Kiso cluster, and the Mongolian cluster. The relationships of these clusters were consistent with their geographical distributions. Basing our assumpti...
Díaz S, Dulout FN, Peral-García P.Genetic polymorphism was analyzed for five blood proteins: albumin - Al, esterase - Es, alpha(1)B-glycoprotein - Xk, transferrin - Tf and hemoglobin - Hb in 200 Thoroughbred (TB) and 124 Argentine Creole (AC) horses. Of the five systems examined, Tf and Hb were not in Hardy-Weinberg equilibrium in either breed and Es was not in equilibrium in the Creole breed. Genetic variability, estimated as average heterozygosity, was higher in AC (H = 0.585 +/- 0.131) than in TB (H = 0.353 +/- 0.065). The genetic differentiation between these two populations (F(ST)) was 0.109. Thus, of the total genetic di...
Schelling C, Hagger C, Pieńkowska A, Siegfried JP, Stranzinger G.A population of Baudet du Poitou donkeys was genetically characterized using microsatellites. The results were used to verify the pedigrees and to estimate the genetic variability. It could be confirmed that a equine parentage test kit works well for donkeys and that by using 13 microsatellites more than 99% of wrong pedigree informations would be detected. The genetic variability was comparable to a representative group of Baudet du Poitou donkeys in France.
Bjørnstad G, Røed KH.Assignment tests have been utilized to investigate population classification, measure genetic diversity and to solve forensic questions. Using microsatellite data from 26 loci genotyped in eight horse breeds we examined how population differentiation, number of scored loci, number of scored animals per breed and loci variability affected individual assignment precision applying log likelihood methods. We found that both genetic differentiation and number of scored loci were highly important for recognizing the breed of origin. When comparing two and two breeds, a proportion of 95% of the most ...
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...
Craigo JK, Leroux C, Howe L, Steckbeck JD, Cook SJ, Issel CJ, Montelaro RC.The genetic variation of equine infectious anaemia virus (EIAV) clearly affects the antigenic properties of the viral envelope; however, effects on immunogenicity remain undefined, although widely assumed. Here, the immunogenicity is reported of a novel, neutralization-resistant, pony-isolate envelope EIAV(PV564DeltaPND) that contains a 14-residue deletion in the designated principal neutralizing domain (PND) of the gp90 protein. Two ponies inoculated with a chimeric virus, EIAV(DeltaPND), containing the EIAV(PV564DeltaPND) envelope in a reference provirus strain, remained asymptomatic through...
Cañon J, Checa ML, Carleos C, Vega-Pla JL, Vallejo M, Dunner S.Partition of the genetic variability, genetic structure and relationships among seven Spanish Celtic horse breeds were studied using PCR amplification of 13 microsatellites on 481 random individuals. In addition, 60 thoroughbred horses were included. The average observed heterozygosity and the mean number of alleles were higher for the Atlantic horse breeds than for the Balearic Islands breeds. Only eight percentage of the total genetic variability could be attributed to differences among breeds (mean FST approximately 0.08; P < 0.01). Atlantic breeds clearly form a separate cluster from th...
Schelling C, Hagger C, Pieńkowska A, Siegfried JP, Stranzinger G.A population of Baudet du Poitou donkeys was genetically characterized using microsatellites. The results were used to verify the pedigrees and to estimate the genetic variability. It could be confirmed that a equine parentage test kit works well for donkeys and that by using 13 microsatellites more than 99% of wrong pedigree informations would be detected. The genetic variability was comparable to a representative group of Baudet du Poitou donkeys in France.
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...
Dugarjaviin M, Yang H.Mongolian horse is a kind of important breed resource of local horses in our country. It has a lot of advantages such as powerful endurance, rough feeding resistance, and strong disease resistance. These advantages have become driving force for in-depth study on Mongolian horse. Genetic diversity can reflect all the genetic information of a species or a variety, namely, it reflects the richness of genetic diversity and confirms the degree of uniqueness of genetic resources through genetic markers. This paper introduces the progress in the study on genetic diversity of Mongolian horse in many a...
Sitzenstock F, Rathke I, Ytournel F, Simianer H.A reference horse-breeding programme with 13500 foals each year was modelled with ZPLAN+. This new software for the optimization of the structures in breeding programmes is based on ZPLAN. In two scenarios, the implementation of a rigorous selection of mares was implemented. In scenario I, the mare performance test was the point of selection, while in scenario II, further information on 20 competitions in two more years is available. These selected mares were used for embryo transfer (ET), partly in combination with multiple ovulation (MOET). The selection intensity and the number of foals out...
Archambault D, Laganière G, St-Laurent G.The genetic variation in equine arteritis virus (EAV) nonstructural (NS) protein-encoding open reading frames (ORF) 3 and 4 genes was investigated. Nucleotide and deduced amino acid sequences from seven different EAV isolates (one European, one American and five Canadian isolates) and the Arvac vaccine strain were compared with those of the Bucyrus reference strain. ORF 3 nucleotide and amino acid sequence identities amongst these isolates (including the Arvac vaccine strain) and the Bucyrus reference strain ranged from 85.6 to 98.8%, and 85.3 to 98.2%, respectively, whereas ORF 4 nucleotide a...
Mata X, Vaiman A, Ducasse A, Diribarne M, Schibler L, Guérin G.Gene characterization is an important feature for genome annotation and more particularly for candidate genes that could be selected in domestic species. Associations between an alpha-actinin-3 gene polymorphism and muscle performance were reported in humans involving a nonsense mutation (R577X) and in mice after inactivation of the gene. Here, we characterized the equine alpha-actinin-3 (ACTN3) gene by sequencing and transcript analysis. The cDNA was determined to be 3.47 kb in length with an open reading frame of 2709 bp expectedly encoding a protein 902 amino acids long. The ACTN3 gene is 1...
Rukavian D, Hasanbasic D, Ramic J, Zahirovic A, Ajanovic A, Beganovic K, Durmic-Pasic A, Kalamujic B, Pojskic N.The focus of this study was on genetic diversity of TB horse population raised in B&H. Genomic DNA was genotyped by using 17 microsatellite markers. A total of 103 alleles were detected. The average number of alleles per locus was 6.059 and effective number of alleles was 3.293. Means of observed and expected heterozygosity were calculated 0.645 and 0.696, respectively. The average PIC values was 0.649 and inbreeding coefficient was 0.090. Based on all observed parameters, ASB2 locus showed the highest genetic diversity while locus HMS2 was the least diverse. These results suggest that the pop...
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...
Woolf CM.Arabian bay horses manifest, on the average, more common white markings in their hind legs than their forelegs (anteroposterior asymmetry) and more common white markings in their left legs than their right legs (directional asymmetry). To determine if genetic variation exists for these types of asymmetry, the phenotypic response was studied in bay foals when their dams and sires were selected for the directions of fore-hind and left-right differences. In the fore-hind studies, the quantitative shifts in the bay foals were in the direction specified by the selection scheme and the observed devi...
Yarali C, Özsensoy Y, Kösemann A, Seker I, Toprak B, Zengin K.This study aimed to determine the effectiveness of parentage verification in Arabian and Thoroughbred horses in Türkiye using microsatellite markers. A total of 813 Arabian and 959 Thoroughbred horses were genotyped using a total of 17 microsatellite markers. The mean effective number of alleles was 3,34 and the mean number of alleles was 7,41 in Arabian horses. It was calculated that the mean He and Ho values in Arabian horses were 0,677 and 0,680, respectively. The mean effective number of alleles was 3,55 and the mean number of alleles was 6,59 in Thoroughbred horses. It was calculated tha...
Sátková-Jakabová D, Trandzík J, Hudecová-Kvasnáková L, Hegedüsová-Zetochová E, Bugarský A, Buleca J, Zöldág L, Jakab F, Fl'ak P.Genetic variation at six microsatellite loci was analysed for five Thoroughbred subpopulations to determine the magnitude of genetic differentiation and the genetic relationships among the subpopulations. Significant deviations from Hardy-Weinberg equilibrium were shown for a number of locus-population combinations, with all subpopulations. The genetic diversities and relationships of five Thoroughbred subpopulations were evaluated using six microsatellites recommended by the International Society of Animal Genetics (ISAG). The allele frequencies, the effective numbers of alleles, and the obse...
The goal of this research was to evaluate the ability of the genotyping information available in the Brazilian Criollo Horse Stud Book to describe the genetic variability of the breed and the exclusion probability determined in comparative tests. Altogether, two softwares were used in the analyses of the available genotypes: Cervus 3.0.3 and Genepop 4.0. Eight microsatellite markers totaled 109 alleles, with an average of 13.6 +/- 0.6 alleles per locus. Large differences between expected and observed heterozygosity were ubiquitous (0.821 +/- 0.07 and 0.470 +/- 0.17, respectively). Although the...
Malmheden Yman I, Sandberg K.Meat from the species horse, donkey and their hybrids, mule/hinny, can be reliably identified by determination of genetic variants of serum albumin by starch gel electrophoresis of meat extracts. Staining of the starch gel for carboxylesterase activity permits differentiation of most horses from donkeys while mules/hinnies cannot be distinguished from horses by their esterase activity alone.
Díaz S, Dulout FN, Peral-García P.Genetic polymorphism was analyzed for five blood proteins: albumin - Al, esterase - Es, alpha(1)B-glycoprotein - Xk, transferrin - Tf and hemoglobin - Hb in 200 Thoroughbred (TB) and 124 Argentine Creole (AC) horses. Of the five systems examined, Tf and Hb were not in Hardy-Weinberg equilibrium in either breed and Es was not in equilibrium in the Creole breed. Genetic variability, estimated as average heterozygosity, was higher in AC (H = 0.585 +/- 0.131) than in TB (H = 0.353 +/- 0.065). The genetic differentiation between these two populations (F(ST)) was 0.109. Thus, of the total genetic di...
Kobayashi I, Nakamura K, Saito I, Akita M, Tozaki T, Miyazaki M, Hano K, Takasu M.For the preservation of Misaki horses, changes in the population structure and genetic diversity of the horses for 5 years were analyzed using population and genotype data from 2015-2020. The microsatellite genotyping was performed, and the average number of alleles (Na), expected heterozygosity (He), and observed value (Ho) were calculated. Moreover, the average generation length (GL) was estimated from the population management record. Then, no significant differences in Na, He, and Ho were found between 2015 and 2020, suggesting their genetic diversity had been maintained for 5 years. Moreo...
Liu L, Castillo-Olivares J, Davis-Poynter NJ, Baule C, Xia H, Belák S.Samples from horses experimentally infected with the "large plaque variant (LP3A+)" of equine arteritis virus were analysed. These included 182 nasal swabs collected from day 1 to 14 post-infection (p.i.), and 21 virus isolates obtained from white blood cells of animals that showed a prolonged viraemia between days 30 to 72 p.i. In order to determine the genetic stability of the virus and particularly to characterise the genetic variants found during the prolonged viraemia, partial sequences of open reading frame 5 (ORF5) encoding glycoprotein 5 (GP5) were generated. Viruses with amino acid su...
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...
Dubrovskaia RM, Starodumov IM, Bannikova LV.The estimation of genetic differentiation between 27 horses breeds originated in USSR, based on serum proteins polymorphism (loci Tf, Al, Es) is shown. Genetical variability among aborigine breeds is higher then among cultural ones. The erosion of gene pool of Przewalski's Horse is explained by special history of this population and a few horses in analyzing group. Genetic distances reflect the directions and intensity of breeding. High genetical distances between Przewalski's Horse, Shetland Pony and other horses obtained could be explained by overcoming the "bottle neck" of selections in bre...
The Journal of heredityOctober 15, 2003
Volume 94, Issue 5 374-380 doi: 10.1093/jhered/esg079
Tozaki T, Takezaki N, Hasegawa T, Ishida N, Kurosawa M, Tomita M, Saitou N, Mukoyama H.The genetic relationships of seven Japanese and four mainland-Asian horse populations, as well as two European horse populations, were estimated using data for 20 microsatellite loci. Mongolian horses showed the highest average heterozygosities (0.75-0.77) in all populations. Phylogenetic analysis showed the existence of three distinct clusters supported by high bootstrap values: the European cluster (Anglo-Arab and thoroughbreds), the Hokkaido-Kiso cluster, and the Mongolian cluster. The relationships of these clusters were consistent with their geographical distributions. Basing our assumpti...
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...
Brandon RB, Giffard JM, Bell K.Single nucleotide polymorphisms (SNPs) in exons 13, 15 and 16 of equine transferrin for common, rare and mutant variants were investigated. Compared with previous work a further 13 SNPs have been identified, allowing for the two previously identified clades to be subdivided into 11 groups. A combination of one or more of eight SNPs can be used to classify the equine variants into these 11 groups, since most are co-inherited. Putative sites of glycosylation in exons 13 and 16 showed no polymorphism, suggesting that presence or absence of sugar moieties does not lead to electrophoretic variation...
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...
Hamann H, Distl O.A data set constituting a total of 310,109 Hanoverian warmblood horses was analyzed to ascertain the genetic variability, coefficients of inbreeding, and gene contributions of foreign populations. The reference population contained all Hanoverian horses born from 1980 to 2000. In addition, Hanoverian stallions born from 1980 to 1995 and Hanoverian breeding mares from the birth years 1980 to 1995 with registered foals were analyzed for the same genetic parameters. The average complete generation equivalent was approximately 8.43 for the reference population. The mean coefficient of inbreeding w...
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...
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...
Orazymbetova Z, Ualiyeva D, Dossybayev K, Torekhanov A, Sydykov D, Mussayeva A, Baktybayev G.Understanding the genetic diversity and structure of domesticated horse () populations is critical for long-term herd management and breeding programs. This study examines 435 horses from Kazakhstan, covering seven groups in three geographic areas using 11 STR markers. Identified are 136 alleles, with the mean number of alleles per locus ranging from 9 to 19. VHL20 is the most variable locus across groups, while loci HTG4, AHT4, AHT5, HTG7, and HMS3 are variable in most populations. The locus AHT5 in the Emba population shows the highest frequency of rare alleles, while the lowest frequency, 0...
Zhang Y, Lv F, Su Y, Zhang H, Zhang B.Streptococcus equi subspecies equi (S. equi) is the causative agent of strangles, which is one of the most common and highly contagious respiratory infectious illnesses in horses. Streptococcus equi (S. equi) is a horse-specific pathogen that originated from the closely related zoonotic pathogen Streptococcus equi subspecies zooepidemicus (S. zooepidemicus). Despite decades of research, the movement of genetic material across host-restricted diseases remains a mystery. Unassigned: Three S. equi donkey isolates (HTP133, HTP232, and HT1112) were recently isolated from a strangles epidemic on don...