Evolutionary biology and horses focus on the study of the evolutionary processes that have shaped the development, adaptation, and diversification of the Equus genus. This field examines the genetic, morphological, and ecological changes that have occurred over millions of years, leading to the modern horse. Researchers explore the transition from small, multi-toed ancestors to the large, single-toed horses of today, analyzing fossil records, genetic data, and environmental factors that influenced these changes. This page compiles peer-reviewed research studies and scholarly articles that investigate the evolutionary history, genetic adaptations, and ecological interactions of horses, providing insights into their development and survival strategies throughout history.
Bogaert L, Willemsen A, Vanderstraeten E, Bracho MA, De Baere C, Bravo IG, Martens A.Squamous cell carcinoma (SCC) represents the most common genital malignant tumor in horses. Similar to humans, papillomaviruses (PVs) have been proposed as etiological agents and recently Equine papillomavirus type 2 (EcPV2) has been identified in a subset of genital SCCs. The goals of this study were (1) to determine the prevalence of EcPV2 DNA in tissue samples from equine genital SCCs, penile intraepithelial neoplasia (PIN) and penile papillomas, using EcPV2-specific PCR, (2) to examine the prevalence of latent EcPV2 infection in healthy genital mucosa and (3) to determine genetic variabili...
Achilli A, Olivieri A, Soares P, Lancioni H, Hooshiar Kashani B, Perego UA, Nergadze SG, Carossa V, Santagostino M, Capomaccio S, Felicetti M....Archaeological and genetic evidence concerning the time and mode of wild horse (Equus ferus) domestication is still debated. High levels of genetic diversity in horse mtDNA have been detected when analyzing the control region; recurrent mutations, however, tend to blur the structure of the phylogenetic tree. Here, we brought the horse mtDNA phylogeny to the highest level of molecular resolution by analyzing 83 mitochondrial genomes from modern horses across Asia, Europe, the Middle East, and the Americas. Our data reveal 18 major haplogroups (A-R) with radiation times that are mostly confined ...
Bower MA, McGivney BA, Campana MG, Gu J, Andersson LS, Barrett E, Davis CR, Mikko S, Stock F, Voronkova V, Bradley DG, Fahey AG, Lindgren G....Selective breeding for speed in the racehorse has resulted in an unusually high frequency of the C-variant (g.66493737C/T) at the myostatin gene (MSTN) in cohorts of the Thoroughbred horse population that are best suited to sprint racing. Here we show using a combination of molecular- and pedigree-based approaches in 593 horses from 22 Eurasian and North-American horse populations, museum specimens from 12 historically important Thoroughbred stallions (b.1764-1930), 330 elite-performing modern Thoroughbreds and 42 samples from three other equid species that the T-allele was ancestral and there...
Nam GH, Ahn K, Bae JH, Cho BW, Park KD, Lee HK, Yang YM, Kim TH, Seong HH, Han K, Kim HS.In the mitochondrial matrix, the OXCT1 gene catalyzes the reversible transfer of coenzyme A from succinyl-CoA to acetoacetate in a reaction related to energy production from ketone bodies. Here, horse OXCT1 gene containing coenzyme A transferase domain was identified in the transcriptome analysis of cDNAs derived from skeletal muscles. Horse OXCT1 gene consisted of 1761 [corrected] nucleotide sequences with an open reading frame of 1560 nucleotides encoding a protein of 520 putative amino acid residues.The number of non-synonymous substitutions was lower than the number of synonymous substitut...
McCue ME, Bannasch DL, Petersen JL, Gurr J, Bailey E, Binns MM, Distl O, Guérin G, Hasegawa T, Hill EW, Leeb T, Lindgren G, Penedo MC, Røed KH....An equine SNP genotyping array was developed and evaluated on a panel of samples representing 14 domestic horse breeds and 18 evolutionarily related species. More than 54,000 polymorphic SNPs provided an average inter-SNP spacing of ∼43 kb. The mean minor allele frequency across domestic horse breeds was 0.23, and the number of polymorphic SNPs within breeds ranged from 43,287 to 52,085. Genome-wide linkage disequilibrium (LD) in most breeds declined rapidly over the first 50-100 kb and reached background levels within 1-2 Mb. The extent of LD and the level of inbreeding were highest in the ...
Miszczak F, Legrand L, Balasuriya UB, Ferry-Abitbol B, Zhang J, Hans A, Fortier G, Pronost S, Vabret A.During the summer of 2007, an outbreak of equine viral arteritis (EVA) occurred in Normandy (France). After investigation, a link was suggested between an EAV carrier stallion (A) and the index premise of the outbreak. The full-length nucleotide sequence analysis of a study reference strain (F27) isolated from the lung of a foal revealed a 12,710 nucleotides EAV genome with unique molecular hallmarks in the 5'UTR leader sequence and the ORF1a sequence encoding the non-structural protein 2. The evolution of the viral population in the persistently infected Stallion A was then studied by cloning...
Kaczensky P, Ganbataar O, Altansukh N, Enkhsaikhan N, Stauffer C, Walzer C.Large mammals re-introduced into harsh and unpredictable environments are vulnerable to stochastic effects, particularly in times of global climate change. The Mongolian Gobi is home to several rare large ungulates such as re-introduced Przewalski's horses (Equus ferus przewalskii) and Asiatic wild asses (Equus hemionus), but also to a millennium-old semi-nomadic livestock herding culture.The Gobi is prone to large inter-annual environmental fluctuations, but the winter 2009/2010 was particularly severe. Millions of livestock died and the Przewalski's horse population in the Gobi crashed. We u...
Yue XP, Qin F, Campana MG, Liu DH, Mao CC, Wang XB, Lan XY, Chen H, Lei CZ.Previous mitochondrial DNA (mtDNA) D-loop and microsatellite studies have shown that Chinese horses have multiple maternal origins and high genetic diversity. To better characterize maternal genetic origins and diversity of Chinese domestic horses, we conducted a comprehensive analysis of 407 complete 1140 bp sequences of the horse mitochondrially encoded cytochrome b (CYTB) gene, including 323 horses from 13 Chinese indigenous breeds and 84 reference sequences from GenBank. A total of 114 haplotypes were identified, of which 73 appeared among the 13 Chinese horse breeds. The high mitochondria...
Capomaccio S, Cappelli K, Cook RF, Nardi F, Gifford R, Marenzoni ML, Passamonti F.Equine infectious anaemia virus (EIAV) is classified within the Retroviridae and, like other lentivirus, has the propensity for considerable antigenic variation. An extensive phylogenetic analysis in Bayesian fashion, with significant amounts of new EIAV gag sequence information, revealed a strong geographic compartmentalization clearly related to the phylogeographic history of modern horses, pointing out that New World EIAV strains form a distinct group with a potentially common origin. This evidence suggests that a single founder event may have occurred during the reintroduction of horses to...
Svensson EM, Telldahl Y, Sjöling E, Sundkvist A, Hulth H, Sjøvold T, Götherström A.Domestication of animals and plants marked a turning point in human prehistory. To date archaeology, archaeozoology and genetics have shed light on when and where all of our major livestock species were domesticated. Phenotypic changes associated with domestication have occurred in all farm animals. Coat colour is one of the traits that have been subjected to the strongest human selection throughout history. Here we use genotyping of coat colour SNPs in horses to investigate whether there were any regional differences or preferences for specific colours associated with specific cultural tradit...
Lippold S, Matzke NJ, Reissmann M, Hofreiter M.DNA target enrichment by micro-array capture combined with high throughput sequencing technologies provides the possibility to obtain large amounts of sequence data (e.g. whole mitochondrial DNA genomes) from multiple individuals at relatively low costs. Previously, whole mitochondrial genome data for domestic horses (Equus caballus) were limited to only a few specimens and only short parts of the mtDNA genome (especially the hypervariable region) were investigated for larger sample sets. Results: In this study we investigated whole mitochondrial genomes of 59 domestic horses from 44 breeds an...
Pruvost M, Bellone R, Benecke N, Sandoval-Castellanos E, Cieslak M, Kuznetsova T, Morales-Muñiz A, O'Connor T, Reissmann M, Hofreiter M, Ludwig A.Archaeologists often argue whether Paleolithic works of art, cave paintings in particular, constitute reflections of the natural environment of humans at the time. They also debate the extent to which these paintings actually contain creative artistic expression, reflect the phenotypic variation of the surrounding environment, or focus on rare phenotypes. The famous paintings "The Dappled Horses of Pech-Merle," depicting spotted horses on the walls of a cave in Pech-Merle, France, date back ~25,000 y, but the coat pattern portrayed in these paintings is remarkably similar to a pattern known as...
Georgescu SE, Manea MA, Dudu A, Costache M.The existence of the Hucul horse on Romanian territory has been documented from the very distant past; today Hucul is a unique breed that is part of the FAO Program for the Preservation of Animal Genetic Resources. We compared Hucul with several primitive European and Asiatic breeds in order to elucidate the origin of these horses. We analyzed a 683-bp mitochondrial DNA (mtDNA) D-loop fragment in a population of Hucul horses and compared the polymorphic sites with sequences from other primitive breeds, including Exmoor, Icelandic Pony, Sorraia, Przewalski Horse, Mongolian Wild Horse, Konik, an...
Campana MG, Stock F, Barrett E, Benecke N, Barker GW, Seetah K, Bower MA.Despite the Icelandic horse enjoying great popularity worldwide, the breed's gene pool is small. This is because of a millennium of isolation on Iceland, population crashes caused by natural disasters and selective breeding. Populations with small effective population sizes are considered to be more at risk of selection pressures such as disease and environmental change. By analysing historic and modern mitochondrial DNA sequences and nuclear coat colour genes, we examined real-time population dynamics in the Icelandic horse over the last 150 years. Despite the small gene pool of this breed, w...
Cothran EG, Canelon JL, Luis C, Conant E, Juras R.Various horse populations in the Americas have an origin in Spain; they are remnants of the first livestock introduced to the continent early in the colonial period (16th and 17th centuries). We evaluated genetic variability within the Venezuelan Criollo horse and its relationship with other horse breeds. We observed high levels of genetic diversity within the Criollo breed. Significant population differentiation was observed between all South American breeds. The Venezuelan Criollo horse showed high levels of genetic diversity, and from a conservation standpoint, there is no immediate danger ...
Lewis NS, Daly JM, Russell CA, Horton DL, Skepner E, Bryant NA, Burke DF, Rash AS, Wood JL, Chambers TM, Fouchier RA, Mumford JA, Elton DM, Smith DJ.Equine influenza virus is a major respiratory pathogen in horses, and outbreaks of disease often lead to substantial disruption to and economic losses for equestrian industries. The hemagglutinin (HA) protein is of key importance in the control of equine influenza because HA is the primary target of the protective immune response and the main component of currently licensed influenza vaccines. However, the influenza virus HA protein changes over time, a process called antigenic drift, and vaccine strains must be updated to remain effective. Antigenic drift is assessed primarily by the hemagglu...
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...
Lippold S, Knapp M, Kuznetsova T, Leonard JA, Benecke N, Ludwig A, Rasmussen M, Cooper A, Weinstock J, Willerslev E, Shapiro B, Hofreiter M.Modern domestic horses display abundant genetic diversity within female-inherited mitochondrial DNA, but practically no sequence diversity on the male-inherited Y chromosome. Several hypotheses have been proposed to explain this discrepancy, but can only be tested through knowledge of the diversity in both the ancestral (pre-domestication) maternal and paternal lineages. As wild horses are practically extinct, ancient DNA studies offer the only means to assess this ancestral diversity. Here we show considerable ancestral diversity in ancient male horses by sequencing 4 kb of Y chromosomal DNA ...
Simmons DR, Letcher PM, Powell MJ, Longcore JE.The order Lobulomycetales contains chytrids from soil, freshwater and marine habitats; environmental DNA sampling has indicated that representatives of this order might be found in deep ocean localities. We describe Alogomyces tanneri as the first lobulomycetalean chytrid isolated from horse manure; A. tanneri is also the first species in the order to possess a rumposome in its zoospore. This species widens the range of habitats, ultrastructural variation and thallus morphology for Lobulomycetales.
Orlando L, Ginolhac A, Raghavan M, Vilstrup J, Rasmussen M, Magnussen K, Steinmann KE, Kapranov P, Thompson JF, Zazula G, Froese D, Moltke I....Second-generation sequencing platforms have revolutionized the field of ancient DNA, opening access to complete genomes of past individuals and extinct species. However, these platforms are dependent on library construction and amplification steps that may result in sequences that do not reflect the original DNA template composition. This is particularly true for ancient DNA, where templates have undergone extensive damage post-mortem. Here, we report the results of the first "true single molecule sequencing" of ancient DNA. We generated 115.9 Mb and 76.9 Mb of DNA sequences from a permafrost-...
Goto H, Ryder OA, Fisher AR, Schultz B, Kosakovsky Pond SL, Nekrutenko A, Makova KD.The endangered Przewalski's horse is the closest relative of the domestic horse and is the only true wild horse species surviving today. The question of whether Przewalski's horse is the direct progenitor of domestic horse has been hotly debated. Studies of DNA diversity within Przewalski's horses have been sparse but are urgently needed to ensure their successful reintroduction to the wild. In an attempt to resolve the controversy surrounding the phylogenetic position and genetic diversity of Przewalski's horses, we used massively parallel sequencing technology to decipher the complete mitoch...
Paria N, Raudsepp T, Pearks Wilkerson AJ, O'Brien PC, Ferguson-Smith MA, Love CC, Arnold C, Rakestraw P, Murphy WJ, Chowdhary BP.Studies of the Y chromosome in primates, rodents and carnivores provide compelling evidence that the male specific region of Y (MSY) contains functional genes, many of which have specialized roles in spermatogenesis and male-fertility. Little similarity, however, has been found between the gene content and sequence of MSY in different species. This hinders the discovery of species-specific male fertility genes and limits our understanding about MSY evolution in mammals. Here, a detailed MSY gene catalogue was developed for the horse--an odd-toed ungulate. Using direct cDNA selection from horse...
Waller AS, Paillot R, Timoney JF.Strangles caused by the host adapted Lancefield group C Streptococcus equi subspecies equi (S. equi) is a frequently diagnosed infectious disease of horses worldwide. Critical to the global success of S. equi is its ability to establish persistent infections within the guttural pouches of recovered apparently healthy horses that can result in transmission to in-contact animals. Recent research has identified key events in the S. equi genome, which occurred during its evolution from an ancestral strain of S. equi subspecies zooepidemicus, that may enhance its ability to evade host innate immune...
Bountouri M, Fragkiadaki E, Ntafis V, Kanellos T, Xylouri E.For first time in Greece equine influenza virus infection was confirmed, by isolation and molecular analysis, as the cause of clinical respiratory disease among unvaccinated horses during 2003 and 2007 outbreaks. Methods: Equine influenza virus (EIV) H3N8 was isolated in MDCK cells from 30 nasal swabs from horses with acute respiratory disease, which were tested positive by Directigen Flu A. Isolation was confirmed by haemagglutination assay and RT-PCR assay of the M, HA and NA gene. Results: HA sequences of the Greek isolates appeared to be more closely related to viruses isolated in early 19...
Geigl EM, Grange T.The Equidae have a long evolutionary history that has interested palaeontologists for a long time. Their morphology-based taxonomy, however, is a matter of controversy. Since most equid species are now extinct, the phylogenetic tree based on genetic data can be established only imperfectly via deduction of present day genomes and little is known about the past genetic diversity of these species. Recent studies of ancient DNA preserved in fossil bones have led to a simplification of the phylogenetic tree and the classification system. The situation is still particularly unclear for the wild ass...
Hampson BA, de Laat MA, Mills PC, Pollitt CC.To investigate the density of the primary epidermal lamellae (PEL) around the solar circumference of the forefeet of near-term fetal feral and nonferal (ie, domesticated) horses. Methods: Left forefeet from near-term Australian feral (n = 14) and domesticated (4) horse fetuses. Methods: Near-term feral horse fetuses were obtained from culled mares within 10 minutes of death; fetuses that had died in utero 2 weeks prior to anticipated birth date and were delivered from live Thoroughbred mares were also obtained. Following disarticulation at the carpus, the left forefoot of each fetus was frozen...
Seyfarth RM, Cheney DL.Convergent evidence from many species reveals the evolutionary origins of human friendship. In horses, elephants, hyenas, dolphins, monkeys, and chimpanzees, some individuals form friendships that last for years. Bonds occur among females, among males, or between males and females. Genetic relatedness affects friendships. In species where males disperse, friendships are more likely among females. If females disperse, friendships are more likely among males. Not all friendships, however, depend on kinship; many are formed between unrelated individuals. Friendships often involve cooperative inte...
Prado JL, Sánchez B, Alberdi MT.Stable isotope ratios (13C/12C and 18O/16O) in fossil teeth and bone provide key archives for understanding the ecology of extinct horses during the Plio-Pleistocene in South America; however, what happened in areas of sympatry between Equus (Amerhippus) and Hippidion is less understood. Results: Here, we use stable carbon and oxygen isotopes preserved in 67 fossil tooth and bone samples for seven species of horses from 25 different localities to document the magnitude of the dietary shifts of horses and ancient floral change during the Plio-Pleistocene. Dietary reconstructions inferred from s...
Acharya KR, Stuart DI, Phillips DC, McKenzie HA, Teahan CG.Similarities in amino acid sequences, three-dimensional structures, and the exon-intron patterns of their genes have indicated that c-type lysozymes and alpha-lactalbumins are homologous proteins, i.e., descended by divergent evolution from a common ancestor. Like the alpha-lactalbumins, echidna milk, horse milk, and pigeon eggwhite lysozymes all bind Ca(II). Models of their three-dimensional structures, based on their amino acid sequences and the known crystal structures of domestic hen eggwhite and human lysozymes and baboon and human alpha-lactalbumins, have been built. The several structur...
Almarzook S, Reissmann M, Brockmann GA.Arabian horse registries classify Arabian horses based on their dam lineages into five main strains. To test the maternal origin of Syrian Arabian horses, 192 horses representing the three major strains Saglawi, Kahlawi, and Hamdani were sequenced for 353 bp of their mitochondrial displacement loop (D-loop) region. Sequencing revealed 28 haplotypes comprising 38 sequence variations. The haplotype diversity values were 0.95, 0.91, and 0.90 in Kahlawi, Hamdani, and Saglawi strains, respectively. The pair-wise population differentiation estimates (Fst) between strains were low, ranging between 0...
Do KT, Cho HW, Badrinath N, Park JW, Choi JY, Chung YH, Lee HK, Song KD, Cho BW.Since ancient days, domestic horses have been closely associated with human civilization. Today, horse racing is an important industry. Various genes involved in energy production and muscle contraction are differentially regulated during a race. Among them, creatine kinase (CK) is well known for its regulation of energy preservation in animal cells. CK is an iso-enzyme, encoded by different genes and expressed in skeletal muscle, heart, brain and leucocytes. We confirmed that the expression of CK-M significantly increased in the blood after a 30 minute exercise period, while no considerable c...
Nemoto M, Nagai M, Tsunemitsu H, Omatsu T, Furuya T, Shirai J, Kondo T, Fujii Y, Todaka R, Katayama K, Mizutani T.Equine group A rotavirus (RVA) G3P[12] and G14P[12] strains cause gastroenteritis in foals worldwide. Both of these strains have been co-circulating in Japan since G14P[12] strains emerged in the late 1990s. Although it is important to comprehensively understand the evolution of RVA strains, whole-genome sequence data on recent equine RVA strains in Japan are lacking. Therefore, in this study, whole-genome analysis of 23 equine RVA isolates from the late 1990s and 2009-2010 and the vaccine strain RVA/Horse-tc/JPN/HO-5/1982/G3P[12] (HO-5) was performed. The G3 strains, including strain HO-5, sh...
da Cruz AB, Hirata S, Dos Santos ME, Mendonça RS.Growing evidence shows a variety of sensorial and motor asymmetries in social and non-social interactions in various species, indicating a lateralized processing of information by the brain. Using digital video cameras on tripods and drones, this study investigated lateralization in frequency and duration of social behavior patterns, in affiliative, agonistic, and resting contexts, in a feral population of horses (Equus ferus caballus) in Northern Portugal, consisting of 37 individuals organized in eight harem groups. Affiliative interactions (including grooming) were more often performed, and...
Cothran EG, van Dyk E, van der Merwe FJ.Genetic variation at 7 blood-group and 10 biochemical genetic loci was examined in 30 horses from a feral herd from the Namib Desert of Namibia, Africa. The observed genetic variability was extremely low compared with that found in domestic horse breeds. The low variation was most probably a result of recent small population size and a small founding population size. Genetic comparison of the Namib horses, which were of unknown origins, to domestic horse breeds, showed that the Namib horses had the highest genetic similarity to Arabian type horses, although they did not closely resemble this t...
Santos Alves J, da Silva Anjos M, Silva Bastos M, Sarmento Martins de Oliveira L, Pereira Pinto Oliveira I, Batista Pinto LF....Equid breeds originating from the Iberian Peninsula and North Africa are believed to have genetically contributed to the formation of breeds and ecotypes from Brazil. The country has numerous breeds and ecotypes of horses and donkeys but there are no extensive studies on maternal genetic diversity and their origins. This study reports the results of the first genetic analysis of all horse and donkey breeds/ecotypes from Brazil based on sequences of the mitochondrial DNA control region (D-loop) whose main objective was to characterize the genetic variation in these animals. These analyses will ...
Perry GH, Makarewicz CA.A new analysis of paleogenomic data from 278 ancient horses (Fages et al. Cellhttp://doi.org/10.1016/j.cell.2019.03.049) finds that this animal - crucially important to many ancient and contemporary human societies for subsistence, transportation, conflict, and more - was domesticated in at least two different regions, but with the geographic and cultural origins of the modern domestic horse lineage remaining unknown. By tracing ancient horse population movements and inferring the spatiotemporal trajectories of phenotypic adaptations, this study provides fresh perspectives on past human group ...
Green J, Xie S, Gan X, Roberts RM.This manuscript describes the cloning of a novel aspartic proteinase expressed in the placenta of the horse (order Perrisodactyla). Evidence for similar genes in the cat (Carnivora) and ruminants (Artiodactyla), indicates that these molecules have been conserved within widely divergent species with distinct types of placentation. Since ePAG is produced by the outer cell layer (trophoblast) of the placenta, it can tentatively be grouped with the pregnancy-associated glycoproteins (PAG) of cattle, sheep, and pig. The high sequence identity that ePAG shares with pepsinogens as well as the PAG, in...
Röhrs M, Ebinger P.Analysed were the brain case capacities and brain weights of wild przewalski horses, przewalski horses from zoological gardens and domesticated horses. Domesticated horses have about 14% less brain case capacity and 16% less brain weight than wild przewalski horses. Przewalski horses from zoological gardens also have about 14% less brain capacity than wild przewalski horses. The brain weight of przewalski horses from zoological gardens shows no difference to the brain weight of domesticated horses. If we look at the brain size, przewalski horses from zoological gardens are domesticated horses....
Lehrman SR, Lahm HW, Miedel MC, Hulmes JD, Li CH.Equine prolactin was determined to be a single chain protein of 199 amino acid containing two tryptophan and six cysteine residues, as found in other mammalian prolactins. The primary sequence of equine prolactin was obtained by automated Edman analyses of S-carboxymethylated protein and proteolytic fragments of modified protein. Of the known prolactin sequences, equine prolactin shows closest homology with porcine (93%) and fin whale (87-91%) prolactins. Genetic mutations have produced changes in 17 of 199 residues of equine prolactin relative to its putative ancestral precursor. Since equine...
Górecka-Bruzda A, Jaworska J, Stanley CR.In captivity, intact male horses, due to their sexual drive, are usually socially isolated from other horses. This lifestyle strongly contrasts with that experienced by horses living in free-roaming, feral, or semi-feral conditions, where adult stallions have several roles in their social group, with successful reproduction being their primary drive. Reproductive skew in wild populations is high; many stallions will fail to reproduce at all, while others achieve high levels of reproductive success, siring a large number of foals. Successful stallions are those with particular characteristics a...
Li S, Zhao G, Han H, Li Y, Li J, Wang J, Cao G, Li X.It is important to resolve the evolutionary history of species genomes as it has affected both genome organization and chromosomal architecture. The rapid innovation in sequencing technologies and the improvement in assembly algorithms have enabled the creation of highly contiguous genomes. DNA Zoo, a global organization dedicated to animal conservation, offers more than 150 chromosome-length genome assemblies. This database has great potential in the comparative genomics field. Results: Using the donkey (Equus asinus asinus, EAS) genome provided by DNA Zoo as an example, the scaffold N50 leng...
Domingo MS, Cantero E, García-Real I, Chamorro Sancho MJ, Martín Perea DM, Alberdi MT, Morales J.The sequence of cheek teeth mineralization, eruption, and replacement of an extinct horse species is here documented with radiological techniques for the first time thanks to the exceptional preservation of Hipparion sp. mandibles from Cerro de los Batallones (Madrid Basin, Spain). The sequence of dental ontogeny in mammals provides valuable insights about life history traits, such as the pace of growth, and about the mode of formation of fossiliferous assemblages. We have determined that the order of permanent cheek teeth mineralization and eruption of hipparionine horses is m1, m2, (p2, p3),...
Sharif MB, Fitak RR, Wallner B, Orozco-terWengel P, Frewin S, Fremaux M, Mohandesan E.New Zealand has the fourth largest feral horse population in the world. The Kaimanawas (KHs) are feral horses descended from various domestic horse breeds released into the Kaimanawa ranges in the 19th and 20th centuries. Over time, the population size has fluctuated dramatically due to hunting, large-scale farming and forestry. Currently, the herd is managed by an annual round-up, limiting the number to 300 individuals to protect the native ecosystem. Here, we genotyped 96 KHs for uniparental markers (mitochondrial DNA, Y-chromosome) and assessed their genetic similarity with respect to other...
Lee K, Pusterla N, Barnum SM, Lee DH, Martínez-López B.Equine influenza virus (EIV) is a highly contagious pathogen of equids, and a well-known burden in global equine health. EIV H3N8 variants seasonally emerged and resulted in EIV outbreaks in the United States and worldwide. The present study evaluated the pattern of cross-regional EIV H3N8 spread and evolutionary characteristics at US and global scales using Bayesian phylogeography with balanced subsampling based on regional horse population size. A total of 297 haemagglutinin (HA) sequences of global EIV H3N8 were collected from 1963 to 2019 and subsampled to global subset (n = 67), raw US ...
Brubaker AS, Coss RG.Habituation to humans was an essential component of horse (Equus caballus ferus) domestication, with the nondomestication of zebras (Equus quagga) possibly reflecting an adaptive constraint on habituation. We present the human hunting hypothesis, arguing that ancestral humans hunted African animals, including zebras, long enough to promote a persistent wariness of humans, whereas a briefer period of hunting horses in Central Asia influenced by glacial cycles was unlikely to produce an equally persistent wariness. An alternative habituation to humans hypothesis, prompted by field observations, ...
Luís C, Bastos-Silveira C, Costa-Ferreira J, Cothran EG, Oom MM.A common female founder individual of the Portuguese horse breeds Sorraia and Lusitano was found while conducting research on the variation of the Lusitano mitochondrial DNA lineages in relation to studbook information. We obtained 416-bp control region sequences from 16 descendents of a female Sorraia founder (Pomba) still represented in the living population of the Lusitano, according to the most recent edition of this breed's studbook. The same haplotype was found for all analysed samples and belongs to the haplogroup described by several authors as having predominantly Iberian, South Ameri...
Myćka G, Musiał AD, Stefaniuk-Szmukier M, Piórkowska K, Ropka-Molik K.The gene encodes peroxisomal acyl-coenzyme A oxidase 1, the first enzyme in the fatty acid β-oxidation pathway, which could be significant for organisms exposed to long periods of starvation and harsh living conditions. We hypothesized that variations within , revealed by RNA Sequencing (RNA-Seq), might be based on adaptation to living conditions and had resulted from selection pressure. There were five different horse breeds used in this study, representing various utility types: Arabian, Thoroughbred, Polish Konik, draft horses, and Hucul. The single-nucleotide polymorphism (SNP) located i...
Padua MB, Kowalski AA, Cañas MY, Hansen PJ.Uterine serpins (USs), designated as SERPINA14, are expressed in the endometrium in response to progesterone. All species identified as having USs exhibit epitheliochorial placentation and are in the Ruminantia and Suidae orders of the Laurasiatheria superorder. The objective was to identify US genes in species within and outside Laurasiatheria and evaluate whether evolution of the US gene was associated with development of the epitheliochorial placenta. Through queries of nucleotide and genomic databases, known US genes were identified (caprine, bovine, porcine, water buffalo), and new US cod...
Hedayat Evrigh N, Omri M, Boustan A, Seyedsharifi R, Vahedi V.The source and history of horse domestication have been studied for decades in biology and archeology. The aim of this study was to evaluate the genetic structure and the genetic relationship between six breeds of native horses using mitochondrial D-loop region. Blood samples were collected from 96 horses. Total DNA was extracted, and 430 bp of D-Loop region (hyper variable) was amplified and sequenced using Sanger sequencing methods. The analysis of data led to identify 48 polymorphic sites that create 52 haplotypes. The plotted phylogenic tree for haplotypes of Iranian native horses is plac...
Pinto P, Hirata S.In some feral horse populations, adult females are either associated with a single male or multiple males (stallions). However, little is known on why such groups with more than one male exist, considering that stallions fight to monopolize females. Body size is often an important determinant of male fighting ability and/or dominance rank and, consequently, reproductive success. Stallions may, therefore, vary in "quality" which could be a differentiating factor between single-stallion and multi-stallion males. We observed feral Garrano horses in Northern Portugal and examined the relationship ...
The Journal of heredityNovember 25, 2014
Volume 106, Issue 1 37-44 doi: 10.1093/jhered/esu074
Khanshour A, Juras R, Blackburn R, Cothran EG.The Canadian breed of horse invokes a fascinating chapter of North American history and as such it is now a heritage breed and the national horse of Canada. The aims of this study were to determine the level of genetic diversity in the Canadian, investigate the possible foundation breeds and the role it had in the development of the US horse breeds, such as Morgan Horse. We tested a total of 981 horses by using 15 microsatellite markers. We found that Canadian horses have high values of genetic diversity indices and show no evidence of a serious loss of genetic diversity and the inbreeding coe...
Elsner J, Hofreiter M, Schibler J, Schlumbaum A.On large geographical scales, changes in animal population distribution and abundance are driven by environmental change due to climatic and anthropogenic processes. However, so far, little is known about population dynamics on a regional scale. We have investigated 92 archaeological horse remains from nine sites mainly adjacent to the Swiss Jura Mountains dating from c. 41,000-5,000 years BP. The time frame includes major environmental turning points such as the Last Glacial Maximum (LGM), followed by steppe vegetation, afforestation and initial re-opening of the landscape by human agricultur...
Bera BC, Virmani N, Shanmugasundaram K, Vaid RK, Singh BK, Gulati BR, Anand T, Barua S, Malik P, Singh RK.The neuraminidase (NA) gene sequences of four Indian equine influenza viruses (EIVs) isolated from epizootic in 2008 and 2009 were analyzed. The phylogenetic relationship and selection pressure of NA genes were established in comparison to other EIVs circulating worldwide along with the domains and motifs of the encoded protein to find out the significance of mutational changes. Among Indian isolates, two amino acid (aa) changes each in Mysore/12/08 (Asn67Tyr & Asp396Gly), Gopeshwar/1/09 (Ile49Val & Asp396Gly), and Uttarkashi/1/09 (Ile49Val & Asp396Gly) isolates were observed in re...
Hu D, Wang C, Ente M, Zhang K, Zhang D, Li X, Li K, Chu H.Intestinal microbiota play an important role in the survival of the host. However, no study to date has elucidated the adjustment of intestinal microbiota of the host during rewilding. Thus, this study aims to describe the intestinal bacterial community of reintroduced Przewalski’s horse (RPH) after being released into their original habitat for approximately 20 years in comparison with that of captive Przewalski’s horse (CPH), sympatric domestic horse (DH) and Mongolian wild ass (MWA) by sequencing the 16S rRNA gene. The results showed that the prevalent bacterial communities were differe...
Nikbakhsh M, Varkoohi S, Seyedabadi HR.Kurdish horse is one of the most valuable horse genetic resources in the Middle East. To assess the genetic diversity of Kurdish horses, Mitochondrial DNA D-loop hyper-variable region1 (HVR1) was sequenced in 29 non-related Kurdish horses which were sampled from diverse geographic regions of Iran. Total DNA was extracted from the collected blood samples by modified salting out method. The HVR1 was amplified by PCR and then sequenced using ABI PRISM BigDyeTM Terminator Cycle Sequencing Ready Reaction Kit. Consequently, the sequences were trimmed to 294 bp using BIOEDIT to become comparable wit...
