Genomics in horses involves the study and analysis of the horse genome to understand genetic variations and their implications for equine health, performance, and breeding. This field encompasses the identification and mapping of genes associated with specific traits, diseases, and conditions in horses. Techniques such as whole-genome sequencing and genome-wide association studies (GWAS) are employed to explore genetic diversity and inheritance patterns among different horse breeds. Genomics provides insights into hereditary disorders, informs selective breeding practices, and aids in the development of personalized veterinary care. This page compiles peer-reviewed research studies and scholarly articles that explore the applications, methodologies, and findings of genomic research in equine science.
Woo PC, Lau SK, Choi GK, Huang Y, Wernery R, Joseph S, Wong EY, Elizabeth SK, Patteril NA, Li T, Wernery U, Yuen KY.Among all known picornaviruses, only two species, equine rhinitis A virus and equine rhinitis B virus (ERBV) are known to infect horses, causing respiratory infections. No reports have described the detection of ERBV in fecal samples of horses and no complete genome sequences of ERBV3 are available. Methods: We performed a molecular epidemiology study to detect ERBVs in horses from Dubai and Hong Kong. Complete genome sequencing of the ERBVs as well as viral loads and genome, phylogenetic and evolutionary analysis were performed on the positive samples. Results: ERBV was detected in four (13.8...
Hristov P, Yordanov G, Ivanova A, Mitkov I, Sirakova D, Mehandzyiski I, Radoslavov G.It is believed that population structure of mountain horse breeds is preserved from any genetic introgression, because of their geographical isolation and specific semi-wild life style of husbandry. Till date there are no molecular data for the Balkan horses. In this study we try to give information about some autochthonous mountain horse breeds from Bulgaria. A total of 121 horses from three different mountain massifs are presented: Stara Planina (the Balkan mountain), the Rhodopes and Rila-Pirin massif were genotyped according to mitochondrial D-loop region. The results showed huge diversity...
Borland EM, Ledermann JP, Powers AM.Highlands J virus (HJV) is an alphavirus closely related to western equine encephalitis virus (WEEV) and eastern equine encephalitis virus (EEEV). HJV is an avian pathogen with the potential for disruption of poultry operations, but is not known to cause human or equine disease. HJV has only been identified in the eastern United States and is thought to have a transmission cycle similar to that of EEEV involving Culiseta melanura mosquitoes and birds. However, HJV is more genetically similar to WEEV and it remains unclear if it may be transmitted by Culex species mosquitoes like WEEV. Seven st...
Lu G, Sun L, Xu T, He D, Wang Z, Ou S, Jia K, Yuan L, Li S.Since 2012, three viruses, known as equine hepacivirus (EqHV), equine pegivirus (EPgV) and Theiler's disease-associated virus (TDAV), have been discovered in equines. Given that these viruses are the newest members of the Flaviviridae family, genomic information concerning circulating EqHV, EPgV and TDAV strains around the world is limited. To date, no genetic surveillance studies have been performed on these three viruses in the equine population of China. Here, a total of 177 serum samples were collected from equines across China between 2014 and 2015. Using PCR, we detected viral RNA in the...
Hall SJ.Accurate measures of effective population sizes (Ne ) in livestock require good quality data and specialized skills for their computation and analysis. Ne can be estimated by Wright's equation Ne =4MF/(M+ F) (M, F being sires and dams, respectively), but this requires assumptions which are often not met. Total census sizes Nc of livestock breeds are collated globally. This paper investigates whether estimates of Ne can be made from Nc ; this would facilitate conservation monitoring. Some Ne methodologies avoid the assumptions of Wright's equation and permit measurement, rather than estimation,...
Franke A, Kershaw O, Jenckel M, König L, Beer M, Hoffmann B, Hoffmann D.The article describes the isolation of a cowpox virus (CPXV) isolate originating from a horse. The skin of a foal, aborted in the third trimester, displayed numerous cutaneous papules. The histological examination showed A-type inclusion bodies within the lesion, typical for CPXV infections. This suspicion was confirmed by real-time PCR where various organs were analyzed. From skin samples, virus isolation was successfully performed. Afterwards, the whole genome of this new isolate "CPXV Amadeus" was sequenced by next-generation technology. Phylogenetic analysis clearly showed that "CPXV Amade...
Vandewege MW, Platt RN, Ray DA, Hoffmann FG.PIWI proteins and PIWI-interacting RNAs (piRNAs) are part of a cellular pathway that has evolved to protect genomes against the proliferation of transposable elements (TEs). PIWIs and piRNAs assemble into complexes that are involved in epigenetic and post-transcriptional repression of TEs. Most of our understanding of the mechanisms of piRNA-mediated TE silencing comes from fruit fly and mouse models. However, even in these well-studied animals it is unclear how piRNA responses relate to variable TE expression and whether the strength of the piRNA response affects TE content over time. Here, w...
Staiger EA, Tseng CT, Miller D, Cassano JM, Nasir L, Garrick D, Brooks SA, Antczak DF.The common equine skin tumors known as sarcoids have been causally associated with infection by bovine papillomavirus (BPV). Additionally, there is evidence for host genetic susceptibility to sarcoids. We investigated the genetic basis of susceptibility to sarcoid tumors on a cohort of 82 affected horses and 270 controls genotyped on a genome-wide platform and two custom panels. A Genome Wide Association Study (GWAS) identified candidate regions on six chromosomes. Bayesian probability analysis of the same dataset verified only the regions on equine chromosomes (ECA) 20 and 22. Fine mapping us...
Staiger EA, Albright JD, Brooks SA.Temperament is a key criterion in the selection of horses for both leisure and competitive riding to ensure optimal performance and safety. The Tennessee Walking Horse (TWH) is described as a calm, docile breed and is often used as a trail, show and pleasure horse. However, among horse owners and caretakers, there are anecdotes supporting familial and disciplinal typical behaviors and personalities. To investigate the contribution of genetics to temperament, we collected a behavior questionnaire, brief training history and identifying information for 276 TWH, as well as blood or hair samples f...
Walter S, Bollenbach A, Doerrbecker J, Pfaender S, Brown RJP, Vieyres G, Scott C, Foster R, Kumar A, Zitzmann N, Griffin S, Penin F, Pietschmann T....Nonprimate hepacivirus (NPHV), the closest homolog of hepatitis C virus (HCV) described to date, has recently been discovered in horses. Even though the two viruses share a similar genomic organization, conservation of the encoded hepaciviral proteins remains undetermined. The HCV p7 protein is localized within endoplasmic reticulum (ER) membranes and is important for the production of infectious particles. In this study, we analyzed the structural and functional features of NPHV p7 in addition to its role during virus assembly. Three-dimensional homology models for NPHV p7 using various nucle...
Kumar N, Bera BC, Greenbaum BD, Bhatia S, Sood R, Selvaraj P, Anand T, Tripathi BN, Virmani N.Equine influenza viruses (EIVs) of H3N8 subtype are culprits of severe acute respiratory infections in horses, and are still responsible for significant outbreaks worldwide. Adaptability of influenza viruses to a particular host is significantly influenced by their codon usage preference, due to an absolute dependence on the host cellular machinery for their replication. In the present study, we analyzed genome-wide codon usage patterns in 92 EIV strains, including both H3N8 and H7N7 subtypes by computing several codon usage indices and applying multivariate statistical methods. Relative synon...
Peglar MT, Nerad TA, Anderson OR.A new species of lobosean amoeba, Stenamoeba polymorpha n. sp., was isolated from the diarrheic stool of a domesticated horse in Great Falls Virginia, U.S. It shares characteristics with the five other described Stenamoeba species. However, electron microscopy revealed S. polymorpha has a substantially thickened cell surface lamina. Under light microscopy, the amoebae had a dynamic polymorphic appearance because hyaloplasm readily formed and resorbed subpseudopodia from any peripheral region of the cell. While in locomotion, the amoebae produced subpseudopodia that led and alternated the dire...
Brinkmann J, Jagannathan V, Drögemüller C, Rieder S, Leeb T, Thaller G, Tetens J.The casein genes are known to be highly variable in typical dairy species, such as cattle and goat, but the knowledge about equine casein genes is limited. Nevertheless, mare milk production and consumption is gaining importance because of its high nutritive value, use in naturopathy, and hypoallergenic properties with respect to cow milk protein allergies. In the current study, the open reading frames of the 4 casein genes CSN1S1 (αS1-casein), CSN2 (β-casein), CSN1S2 (αS2-casein), and CSN3 (κ-casein) were resequenced in 253 horses of 14 breeds. The analysis revealed 21 nonsynonymous nucle...
Griffith OW, Brandley MC, Whittington CM, Belov K, Thompson MB.In oviparous amniotes (reptiles, birds, and mammals) the chorioallantoic membrane (CAM) lines the inside of the egg and acts as the living point of contact between the embryo and the outside world. In livebearing (viviparous) amniotes, communication during embryonic development occurs across placental tissues, which form between the uterine tissue of the mother and the CAM of the embryo. In both oviparous and viviparous taxa, the CAM is at the interface of the embryo and the external environment and can transfer signals from there to the embryo proper. To understand the evolution of placental ...
Schrimpf R, Gottschalk M, Metzger J, Martinsson G, Sieme H, Distl O.Stallion fertility is an economically important trait due to the increase of artificial insemination in horses. The availability of whole genome sequence data facilitates identification of rare high-impact variants contributing to stallion fertility. The aim of our study was to genotype rare high-impact variants retrieved from next-generation sequencing (NGS)-data of 11 horses in order to unravel harmful genetic variants in large samples of stallions. Methods: Gene ontology (GO) terms and search results from public databases were used to obtain a comprehensive list of human und mice genes pred...
Yang Y, Zhu Q, Liu S, Zhao C, Wu C.The origin of domestic horses in China was a controversial issue and several hypotheses including autochthonous domestication, introduction from other areas, and multiple-origins from both introduction and local wild horse introgression have been proposed, but none of them have been fully supported by DNA data. In the present study, mitochondrial DNA (mtDNA) sequences of 714 Chinese indigenous horses were analyzed. The results showed that Chinese domestic horses harbor some novel mtDNA haplogroups and suggested that local domestication events may have occurred, but they are not the dominant ha...
Lee JH, Song KD, Kim JM, Leem HK, Park KD.Jeju horse (Natural Monument number 347) is a breed of horse that has experienced long-term isolation and domestication in Jeju Island, South Korea. We evaluated genetic features of this breed, including SNP, by whole-genome resequencing using an Illumina HiSeq 2000. A total of 5,986,852 SNP were identified in 4 Jeju horses and were divided into homozygous and heterozygous SNP (2,357,099 and 3,629,753 SNP, respectively). It revealed that 63.8% of these SNP resided in intergenic regions. Immune response genes with nonsynonymous SNP were overrepresented in Jeju horses as evidenced by Gene Ontolo...
Velie BD, Shrestha M, Franҫois L, Schurink A, Tesfayonas YG, Stinckens A, Blott S, Ducro BJ, Mikko S, Thomas R, Swinburne JE, Sundqvist M....While susceptibility to hypersensitive reactions is a common problem amongst humans and animals alike, the population structure of certain animal species and breeds provides a more advantageous route to better understanding the biology underpinning these conditions. The current study uses Exmoor ponies, a highly inbred breed of horse known to frequently suffer from insect bite hypersensitivity, to identify genomic regions associated with a type I and type IV hypersensitive reaction. A total of 110 cases and 170 controls were genotyped on the 670K Axiom Equine Genotyping Array. Quality control ...
Gardner SN, McLoughlin K, Be NA, Allen J, Weaver SC, Forrester N, Guerbois M, Jaing C.Venezuelan equine encephalitis virus (VEEV) is a mosquito-borne alphavirus that has caused large outbreaks of severe illness in both horses and humans. New approaches are needed to rapidly infer the origin of a newly discovered VEEV strain, estimate its equine amplification and resultant epidemic potential, and predict human virulence phenotype. We performed whole genome single nucleotide polymorphism (SNP) analysis of all available VEE antigenic complex genomes, verified that a SNP-based phylogeny accurately captured the features of a phylogenetic tree based on multiple sequence alignment, an...
Nemoto M, Bannai H, Tsujimura K, Yamanaka T, Kondo T.A Getah virus strain isolated during an outbreak in racehorses in Japan in 2014 (14-I-605) was compared with the vaccine strain isolated in 1978 (MI-110). A comparison of the genome sequences of these strains revealed seven amino acid substitutions in non-structural protein 3, and one or two substitutions in each of other non-structural proteins. In contrast, the structural proteins were highly conserved (99.8-99.9 % amino acid sequence identity). Horse antisera raised against the MI-110 strain showed similar virus-neutralization titers against both MI-110 and 14-I-605 strains (512 and 256, r...
West J, Gill WW.Genome editing in large animals has tremendous practical applications, from more accurate models for medical research through improved animal welfare and production efficiency. Although genetic modification in large animals has a 30 year history, until recently technical issues limited its utility. The original methods - pronuclear injection and integrating viruses - were plagued with problems associated with low efficiency, silencing, poor regulation of gene expression, and variability associated with random integration. With the advent of site specific nucleases such as TALEN and CRISPR/Cas9...
Szcześniak KA, Ciecierska A, Ostaszewski P, Sadkowski T.Adult skeletal muscle myogenesis depends on the activation of satellite cells that have the potential to differentiate into new fibers. Gamma-oryzanol (GO), a commercially available nutriactive phytochemical, has gained global interest on account of its muscle-building and regenerating effects. Here, we investigated GO for its potential influence on myogenesis, using equine satellite cell culture model, since the horse is a unique animal, bred and exercised for competitive sport. To our knowledge, this is the first report where the global gene expression in cultured equine satellite cells has ...
Duan H, Gao JF, Su X, Fu X, Yue DM, Gao Y, Qiu JH, Wang CR.Triodontophorus spp. parasitizes the large intestine of equine, causing strongylid diseases. The present study assessed genetic variation in five gene regions within and between Triodontophorus brevicauda and Triodontophorus nipponicus from Heilongjiang Province and the Inner Mongolia Autonomous region. The five gene markers were three mitochondrial (mt) genes, cytochrome c oxidase subunit I (cox1), NADH dehydrogenase subunit 5 (nad5), cytochrome b (cytb); and two ribosomal RNA genes, the internal transcribed spacer 1 (ITS1) and the internal transcribed spacer 2 (ITS2). Partial (p) sequences o...
Roy Chowdhury P, DeMaere M, Chapman T, Worden P, Charles IG, Darling AE, Djordjevic SP.Clostridium difficile infections (CDI) are a significant health problem to humans and food animals. Clostridial toxins ToxA and ToxB encoded by genes tcdA and tcdB are located on a pathogenicity locus known as the PaLoc and are the major virulence factors of C. difficile. While toxin-negative strains of C. difficile are often isolated from faeces of animals and patients suffering from CDI, they are not considered to play a role in disease. Toxin-negative strains of C. difficile have been used successfully to treat recurring CDI but their propensity to acquire the PaLoc via lateral gene transfe...
Mach N, Plancade S, Pacholewska A, Lecardonnel J, Rivière J, Moroldo M, Vaiman A, Morgenthaler C, Beinat M, Nevot A, Robert C, Barrey E.The adaptive response to extreme endurance exercise might involve transcriptional and translational regulation by microRNAs (miRNAs). Therefore, the objective of the present study was to perform an integrated analysis of the blood transcriptome and miRNome (using microarrays) in the horse before and after a 160 km endurance competition. A total of 2,453 differentially expressed genes and 167 differentially expressed microRNAs were identified when comparing pre- and post-ride samples. We used a hypergeometric test and its generalization to gain a better understanding of the biological functio...
Ghosh S, Das PJ, McQueen CM, Gerber V, Swiderski CE, Lavoie JP, Chowdhary BP, Raudsepp T.We explored the involvement of genomic copy number variants (CNVs) in susceptibility to recurrent airway obstruction (RAO), or heaves-an asthmalike inflammatory disease in horses. Analysis of 16 RAO-susceptible (cases) and six RAO-resistant (control) horses on a custom-made whole-genome 400K equine tiling array identified 245 CNV regions (CNVRs), 197 previously known and 48 new, distributed on all horse autosomes and the X chromosome. Among the new CNVRs, 30 were exclusively found in RAO cases and were further analyzed by quantitative PCR, including additional cases and controls. Suggestive as...
Raudsepp T, Chowdhary BP.The association between chromosomal abnormalities and reduced fertility in domestic animals is well recorded and has been studied for decades. Chromosome aberrations directly affect meiosis, gametogenesis, and the viability of zygotes and embryos. In some instances, balanced structural rearrangements can be transmitted, causing fertility problems in subsequent generations. Here, we aim to give a comprehensive overview of the current status and future prospects of clinical cytogenetics of animal reproduction by focusing on the advances in molecular cytogenetics during the genomics era. We descr...
Heuer C, Scheel C, Tetens J, Kühn C, Thaller G.Categorical traits without ordinal representation of classes do not qualify for threshold models. Alternatively, the multinomial problem can be assessed by a sequence of independent binary contrasts using schemes such as one-vs-all or one-vs-one. Class probabilities can be arrived at by normalization or pair-wise coupling strategies. We assessed the predictive ability of whole-genome regression models and support vector machines for the classification of horses into four German Warmblood breeds. Results: Prediction accuracies of leave-one-out cross-validation were high and ranged from 0.75 to ...
Mehdizadeh Gohari I, Kropinski AM, Weese SJ, Parreira VR, Whitehead AE, Boerlin P, Prescott JF.The recent discovery of a novel beta-pore-forming toxin, NetF, which is strongly associated with canine and foal necrotizing enteritis should improve our understanding of the role of type A Clostridium perfringens associated disease in these animals. The current study presents the complete genome sequence of two netF-positive strains, JFP55 and JFP838, which were recovered from cases of foal necrotizing enteritis and canine hemorrhagic gastroenteritis, respectively. Genome sequencing was done using Single Molecule, Real-Time (SMRT) technology-PacBio and Illumina Hiseq2000. The JFP55 and JFP838...
Frischknecht M, Flury C, Leeb T, Rieder S, Neuditschko M.Shetland ponies were selected for numerous traits including small stature, strength, hardiness and longevity. Despite the different selection criteria, Shetland ponies are well known for their small stature. We performed a selection signature analysis including genome-wide SNPs of 75 Shetland ponies and 76 large-sized horses. Based upon this dataset, we identified a selection signature on equine chromosome (ECA) 1 between 103.8 Mb and 108.5 Mb. A total of 33 annotated genes are located within this interval including the IGF1R gene at 104.2 Mb and the ADAMTS17 gene at 105.4 Mb. These two ge...
Pawlina-Tyszko K, Gurgul A, Szmatoła T, Ropka-Molik K, Semik-Gurgul E, Klukowska-Rötzler J, Koch C, Mählmann K, Bugno-Poniewierska M.Although they are the most common neoplasms in equids, sarcoids are not fully characterized at the molecular level. Therefore, the objective of this study was to characterize the landscape of structural rearrangements, such as copy number variation (CNV) and copy neutral loss of heterozygosity (cnLOH), in the genomes of sarcoid tumor cells. This information will not only broaden our understanding of the characteristics of this genome but will also improve the general knowledge of this tumor and the mechanisms involved in its generation. To this end, Equine SNP64K Illumina microarrays were appl...
Radtke CL, Nino-Fong R, Rodriguez-Lecompte JC, Esparza Gonzalez BP, Stryhn H, McD○ LA.The objectives of this study were to use non-equilibrium gravitational field-flow fractionation (GrFFF), an immunotag-less method of sorting mesenchymal stem cells (MSCs), to sort equine muscle tissue-derived mesenchymal stem cells (MMSCs) and bone marrow-derived mesenchymal stem cells (BMSC) into subpopulations and to carry out assays in order to compare their osteogenic capabilities. Cells from 1 young adult horse were isolated from left semitendinosus muscle tissue and from bone marrow aspirates of the fourth and fifth sternebrae. Aliquots of 800 × 10(3) MSCs from each tissue source were s...
Gurgul A, Jasielczuk I, Semik-Gurgul E, Pawlina-Tyszko K, Szmatoła T, Polak G, Bugno-Poniewierska M.The current role of the horse as a companion animal resulted in a decrease of interest in breeding and usage of draft horses. This meant that the population of cold-blooded horses in Poland has been dramatically reduced during the last decades. To avoid impoverishment of the gene pool of the local horse population, a conservation program was established which involves draft horses and other local horse breeds. The draft horses bred in Poland can be subdivided in a few horse types of which the most widespread and consolidated are Sztumski and Sokólski horses. These two subpopulations are pheno...
Vereecke N, Vandekerckhove A, Theuns S, Haesebrouck F, Boyen F.Actinobacillus equuli is mostly associated with disease in horses and is most widely known as the causative agent of sleepy foal disease. Even though existing phenotypic tools such as biochemical tests, 16S rRNA gene sequencing, and Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) can be used to identify members of the Actinobacillus genus, these methods struggle to differentiate between certain species and do not allow strain, virulence, and antimicrobial susceptibility typing. Hence, we performed in-depth analysis of 24 equine Actinobacillus isolate...
Sundararaman B, Vershinina AO, Hershauer S, Kapp JD, Dunn S, Shapiro B, Green RE.Hybridization capture approaches allow targeted high-throughput sequencing analysis at reduced costs compared to shotgun sequencing. Hybridization capture is particularly useful in analyses of genomic data from ancient, environmental, and forensic samples, where target content is low, DNA is fragmented and multiplex PCR or other targeted approaches often fail. Here, we describe a DNA bait synthesis approach for hybridization capture that we call Circular Nucleic acid Enrichment Reagent, or CNER (pronounced 'snare'). The CNER method uses rolling-circle amplification followed by restriction dige...
Wang X, Bou G, Zhang X, Tao L, Shen Y, Na R, Liu G, Ren H, Ren X, Song L, Su S, Bai D, Zhao Y, Li B, Dugarjaviin M.Having considered that the current methods are costly and time-consuming, we designed an only 3 pairs primer-based PCR test to accurately identify the species and gender in horses, donkeys, mules and hinnies. Through a thorough sequence comparison between horse and donkey's highly similar genomes, and a vast amount of preliminary confirmation, we found that three fragments, CNGB3 gene on an autosome, displacement loop region on mitochondrial DNA and SRY genes on chromosome Y, within these equine DNA, are enough to enable us achieving our goal. The PCR test described here would be an economical...
Gardner SN, McLoughlin K, Be NA, Allen J, Weaver SC, Forrester N, Guerbois M, Jaing C.Venezuelan equine encephalitis virus (VEEV) is a mosquito-borne alphavirus that has caused large outbreaks of severe illness in both horses and humans. New approaches are needed to rapidly infer the origin of a newly discovered VEEV strain, estimate its equine amplification and resultant epidemic potential, and predict human virulence phenotype. We performed whole genome single nucleotide polymorphism (SNP) analysis of all available VEE antigenic complex genomes, verified that a SNP-based phylogeny accurately captured the features of a phylogenetic tree based on multiple sequence alignment, an...
Gmel AI, Burger D, Neuditschko M.The use of frozen-thawed semen is an important reproduction tool to preserve the biodiversity of small, native horse breeds such as the Franches-Montagnes (FM). However, not all stallions produce cryotolerant semen with a progressive motility after thaw ≥ 35%. To improve our understanding of the genetic background of male fertility traits in both fresh and frozen-thawed semen, we performed genome-wide association studies (GWAS) on gel-free volume, sperm cell concentration, total sperm count, and progressive motility in fresh and frozen-thawed semen from 109 FM stallions using 335,494 genome-...
Bengtsson RJ, Wee BA, Yebra G, Bacigalupe R, Watson E, Guedes RMC, Jacobson M, Stadejek T, Archibald AL, Fitzgerald JR, Ait-Ali T.Lawsonia intracellularis is a Gram-negative obligate intracellular bacterium that is the aetiological agent of proliferative enteropathy (PE), a common intestinal disease of major economic importance in pigs and other animal species. To date, progress in understanding the biology of L. intracellularis for improved disease control has been hampered by the inability to culture the organism in vitro. In particular, our understanding of the genomic diversity and population structure of clinical L. intercellularis is very limited. Here, we utilized a metagenomic shotgun approach to directly sequenc...
Palomino Lago E, Jelbert ER, Baird A, Lam PY, Guest DJ.Persistent inflammation is associated with the poor regeneration of musculoskeletal tissues. Embryonic stem cells (ESCs) have an attenuated response to inflammatory cytokines, but there are mixed reports on the response of induced pluripotent stem cells (iPSCs) to inflammation. Horses provide a relevant large animal model for studying musculoskeletal tissue diseases and the testing of novel therapies. The aim of this study was to determine if equine iPSCs are responsive to the inflammatory cytokines IL-1β, TNFα and IFN-γ in their undifferentiated state, or following differentiation into ten...
Lepage N, St-Laurent G, Carman S, Archambault D.The genetic variation in equine arteritis virus (EAV) Gs protein encoding gene was investigated. Nucleic and deduced amino acid sequences from eight different EAV isolates (one European, two American and five Canadian isolates) were compared with those of the Bucyrus reference strain. Nucleotide and amino acid identities between these isolates and the Bucyrus reference strain ranged from 92.3 to 96.4%, and 93.2 to 95.5%, respectively. However, phylogenetic tree analysis and estimation of genetic distances based on the Gs protein encoding gene sequences showed that the European prototype Vienna...
von Samson-Himmelstjerna G, Janssen IJI, Ramünke S, Goday C, Borges FA, Koudela B, Niedźwiedź A, Tomczuk K, Studzińska MB, Kornas S, Krücken J.Equines were over decades considered to be infected by two morphologically virtually indistinguishable ascarid species, Parascaris univalens and Parascaris equorum. Reliable species discrimination is only possible using enzyme isoelectric focussing and karyotyping with P. univalens having one and P. equorum two chromosome pairs. However, presumably the complexity of both methods prevented their routine use in nearly all previous studies about prevalence and drug resistance of Parascaris spp. These have barely been performed on the species level although most studies stated presence of one or t...
Savage VL, Christley R, Pinchbeck G, Morrison LJ, Hodgkinson J, Peachey LE.Trypanosomosis is a major cause of morbidity and mortality in working equids in The Gambia. Recently, a progressive, severe neurological syndrome characterised by a diffuse lymphoplasmacytic meningoencephalitis has been identified and associated with Trypanosoma brucei infection of the central nervous system. The pathogenesis of cerebral trypanosomosis is unclear and the clinical syndrome not well described. This observational cross-sectional study aimed to identify host and parasite related risk factors associated with the development of cerebral trypanosomosis and to describe the neurologica...
Khusro A, Aarti C, Salem AZM, Pliego AB, Rivas-Caceres RR.Methane (CH) emission from nonruminant livestock, particularly equines, is a colossal burden for veterinarians worldwide. In view of this, the present context was investigated to predict the antimethanogenic attributes of Moringa oleifera L. associated phytocomponents by targeting methyl-coenzyme M reductase (MCR) receptor in horses using in silico tools. Initially, the pharmacokinetics and ADME (absorption, distribution, metabolism, and excretion) properties of 26 phytocomponents were analyzed using Lipinski's rule of five and Swiss ADME tool, respectively. Among all the tested phytocomponent...
Xie J, Tong P, Zhang L, Ren M, Song X, Jia C, Palidan N, Zhang L, Kuang L.In November 2018, an outbreak of respiratory disease occurred in foals at an equestrian club in Changji, northern Xinjiang, China. We applied viral metagenomics to investigate this outbreak and identify potential pathogens involved in this equine respiratory syndrome. The metagenomics data revealed the presence of sequences matching those of equid herpesvirus (EHV) 2, 4, and 5. PCR with specific primers targeting ORF33 of EHV-4 and ORF8 of EHV-2 and EHV-5 revealed coinfection with these viruses in this respiratory syndrome. To investigate the prevalence of these viruses in China, 453 nasal swa...
Salek Ardestani S, Zandi MB, Vahedi SM, Janssens S.The genetic structure and characteristics of Iranian native breeds are yet to be comprehensibly investigated and studied. Therefore, we employed genomic information of 364 Iranian native horses representing the Asil (n = 109), Caspian (n = 40), Dareshuri (n = 44), Kurdish (n = 95), and Turkoman (n = 76) breeds to reveal the genetic structure and characteristics. For these and 19 other horse breeds, principal component analysis, Bayesian model-based, Neighbor-Net, and bootstrap-based TreeMix approaches were applied to investigate and compare their genetic structure. Additionally, thre...
Looft C, Paul S, Philipp U, Regenhard P, Kuiper H, Distl O, Chowdhary BP, Leeb T.Defensins are a family of evolutionary ancient antimicrobial peptides consisting of three sub-families: alpha-, beta- and theta-defensins. This investigation was focused on the genomic characterization of equine beta-defensins and the investigation of the potential clustering of beta-defensin genes in the equine genome. Six genomic BAC clones were isolated from the CHORI-241 library and one of these was mapped by FISH to ECA 27q17. This location was confirmed by RH-mapping. The contiguous 212 kb sequence of this clone was determined. Sequence analysis revealed the identification of ten pseudog...
Studdert MJ, Crabb BS, Ficorilli N.The restriction endonuclease DNA fingerprints of 57 isolates of equine herpesvirus 1 (EHV1; equine abortion virus) from abortion, perinatal foal mortalities and encephalitis from 15 epidemics that occurred in Australasia between 1975 and 1989 were examined using the enzymes Bam HI, EcoRI and Bgl II. There was a remarkable degree of uniformity in the restriction patterns; mobility differences were observed in only 14 of 52 (27%) of the fragments. Twelve of these 14 fragments were located within the repeat structures that bracket the unique short region of the genome or were located at the left ...
Flack N, Hughes L, Cassens J, Enriquez M, Gebeyehu S, Alshagawi M, Hatfield J, Kauffman A, Brown B, Klaeui C, Mabrouk IF, Walls C, Yeater T, Rivas A....The Przewalski's horse (Equus ferus przewalskii) is an endangered equid native to the steppes of central Asia. After becoming extinct in the wild multiple conservation efforts convened to preserve the species, including captive breeding programs, reintroduction and monitoring systems, protected lands, and cloning. Availability of a highly contiguous reference genome is essential to support these continued efforts. We used Oxford Nanopore sequencing to produce a scaffold-level 2.5 Gb nuclear assembly and 16,002 bp mitogenome from a captive Przewalski's mare. All assembly drafts were generated f...
Šenica P, Žele Vengušt D, Vengušt G, Kuhar U.Rotaviruses A (RVA) are a major cause of acute viral gastroenteritis in humans worldwide and are responsible for about two million hospitalizations per year. They can also infect other mammals such as pigs, calves, goats, lambs, and horses, in which they are also considered a major cause of viral diarrhea. While RVA is well studied in humans and domestic animals, its occurrence in wild ruminants is not well known. The RVA genome is a double-stranded RNA consisting of 11 segments, and genotyping is based on the VP7 (G) and VP4 (P) segments. Currently, there are 42G genotypes and 58P genotypes. ...
Wang C, Zeng Y, Wang J, Wang T, Li X, Shen Z, Meng J, Yao X.Racing performance traits are the main indicators for evaluating the performance and value of sport horses. The aim of this study was to identify the key genes for racing performance traits in Yili horses by performing a genome-wide association study (GWAS). Breeding values for racing performance traits were calculated for Yili horses (n = 827) using an animal model. Genome-wide association analysis of racing performance traits in horses (n = 236) was carried out using the Blink, and FarmCPU models in GAPIT software, and genes within the significant regions were functionally annotated....
Parsad R, Bagiyal M, Ahlawat S, Arora R, Gera R, Chhabra P, Sharma U.Donkeys (Equus asinus) have played a vital role in agriculture, transportation, and companionship, particularly in developing regions where they are indispensable working animals. The domestication of donkeys marked a significant turning point in human history, as they became essential for transportation, agriculture, and trade, especially in arid and semi-arid areas where their resilience and endurance were highly valued. In modern society, donkeys are indispensable due to their diversified applications, including meat, dairy, medicine, and functional bioproducts, supporting economic, cultura...
Diekmann I, Krücken J, Kuzmina TA, Bredtmann CM, Louro M, Kharchenko VA, Tzelos T, Matthews JB, Madeira de Carvalho LM, von Samson-Himmelstjerna G.Morphologically, 64 strongylid species have been described in equines. Co-infections are common, with up to 29 species reported in a single horse. Morphological identification of these species is time consuming and requires expert knowledge due to their similar appearance. Therefore, non-invasive identification methods are needed. DNA barcoding offers a rapid and reliable tool for species identification and the discovery of cryptic species for these most common parasitic nematodes of equines. In total, 269 COI and 312 ITS-2 sequences from 27 equine Strongylidae species, including sequences fro...
Musiał AD, Radović L, Stefaniuk-Szmukier M, Bieniek A, Wallner B, Ropka-Molik K.Polish Konik remains one of the most important horse breeds in Poland. The primitive, native horses with a stocky body and mouse-like coat color are protected by a conservation program, while their Polish population consists of about 3,480 individuals, representing 16 dam and six sire lines. To define the population's genetic structure, mitochondrial DNA and Y chromosome sequence variables were identified. The mtDNA whole hypervariable region analysis was carried out using the Sanger sequencing method on 233 Polish Koniks belonging to all dam lines, while the Y chromosome analysis was performe...
While CENP-A is the epigenetic determinant of the centromeric function, the role of CENP-B, a centromeric protein binding a specific DNA sequence, the CENP-B-box, remains elusive. In the few mammalian species analyzed so far, the CENP-B box is contained in the major satellite repeat that is present at all centromeres, with the exception of the Y chromosome. We previously demonstrated that, in the genus Equus, numerous centromeres lack any satellite repeat. Results: In four Equus species, CENP-B is expressed but does not bind the majority of satellite-based centromeres, or the satellite-free on...
Dementieva N, Nikitkina E, Shcherbakov Y, Nikolaeva O, Mitrofanova O, Ryabova A, Atroshchenko M, Makhmutova O, Zaitsev A.The specifics of breeding and selection significantly affect genetic diversity and variability within a breed. We present the data obtained from the genetic analysis of 21 thoroughbred and warmblood horse breeds. The most detailed information is described from the following breeds: Arabian, Trakehner, French Trotter, Standardbred, and Soviet Heavy Horse. The analysis of 509,617 SNP variants in 87 stallions from 21 populations made it possible to estimate the genetic diversity at the genome-wide level and distinguish the studied horse breeds from each other. In this study, we searched for heter...