DNA in horses refers to the genetic material that carries the hereditary information necessary for the growth, development, functioning, and reproduction of equine species. It consists of sequences of nucleotides that encode the genetic instructions used in the development and functioning of horses. DNA analysis in horses can provide insights into genetic diversity, lineage, and breed characteristics. It is also utilized in identifying genetic disorders, understanding hereditary traits, and assisting in selective breeding programs. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and applications of DNA analysis in equine genetics and breeding.
Li Y, Liu C, Liu Q, Liu W.Ligilactobacillus equi is common in the horse intestine, alleviates the infection of Salmonella, and regulates intestinal flora. Despite this, there have been no genomic studies on this species. Here, we provide the genomic basis for adaptation to the intestinal habitat of this species. We sequenced the genome of L. equi IMAU81196, compared this with published genome information from three strains in NCBI, and analyzed genome characteristics, phylogenetic relationships, and functional genes. The mean genome size of L. equi strains was 2.08 ± 0.09 Mbp, and the mean GC content was 39.17% ± 0.1...
Yun J, Oyungerel B, Kong HS.This study aimed to identify the genetic diversity and population structure of Mongolian horse populations according to the province of residence (Khentii, KTP; Uvs, USP; Omnogovi and Dundgovi, GOP; Khovsgol, KGP) using 14 microsatellite (MS) markers. Methods: A total of 269 whole blood samples were obtained from the four populations (KTP, USP, GOP, KGP) geographically distinct provinces. Multiplex polymerase chain reaction (PCR) was conducted using 14 MS markers (AHT4, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, and VHL20), as recommended by the International So...
Tong P, Duan R, Palidan N, Deng H, Duan L, Ren M, Song X, Jia C, Tian S, Yang E, Kuang L, Xie J.EHV-1 is one of the most serious viral pathogens that frequently cause abortion in horses around the world. However, so far, relatively little information is available on EHV-1 infections as they occur in China. In January 2021, during an abortion storm which occurred in Yili horses at the Chinese State Studs of Zhaosu (North Xinjiang, China), 43 out of 800 pregnant mares aborted. Results: PCR detection revealed the presence of EHV-1 in all samples as the possible cause of all abortions, although EHV-4, EHV-2 and EHV-5 were also found to circulate in the aborted fetuses. Furthermore, the parti...
Hong JH, Oh CS, Kim S, Kang IU, Shin DH.To understand the domestication and spread of horses in history, genetic information is essential. However, mitogenetic traits of ancient or medieval horses have yet to be comprehensively revealed, especially for East Asia. This study thus set out to reveal the maternal lineage of skeletal horse remains retrieved from a 15th century archaeological site (Gongpyeongdong) at Old Seoul City in South Korea. Methods: We extracted DNA from the femur of Equus caballus (SNU-A001) from Joseon period Gongpyeongdong site. Mitochondrial (mt) DNA (HRS 15128-16116) of E. caballus was amplified by polymerase ...
Nazari F, Seyedabadi HR, Noshary A, Emamjomeh-Kashan N, Banabazi MH.The genetic diversity and genomic regions being under putative natural selection in Kurdish horse population were studied. The samples from 72 horses were genotyped by using GGP Equine 70K SNP arrays. The Ne Slope (NeS) analyses revealed that a sharp decline in Ne has probably occurred around four generations ago, and high frequency of ROH with 2-4 Mbp in length suggested that the inbreeding has probably occurred around 20 generations ago. The effective population size (Ne) was 104 horses up to three generations ago and the average inbreeding (FROH) was 0.047(± 0.045). Using de-correlated com...
Quiñones-Pérez C, Martínez A, Ortiz I, Crespo F, Vega-Pla JL.Despite the advances in reproductive technology, there is still a considerable number of low sperm quality cases in stallions. Recent studies in humans have detected several seminal microflora-spermatozoa associations behind some idiopathic infertility cases. However, no studies are available on horses, and there is limited information on the microflora present in stallion ejaculates. Accordingly, the objective of this study was to examine associations to the presence of bacteria families with five sperm quality parameters: concentration, total number of spermatozoa, total and progressive moti...
Patterson Rosa L, Campos FA, Martin K, Vierra M, Foster G, Lundquist E, Brooks SA, Lafayette C.Pedigrees and horse written ancestry contain numerous inconsistencies and divergence between farm histories, owner accounts and registration records. In particular, the origins of the Brazilian Mangalarga, or "Mangalarga Paulista'' horse breed is controversial, and the breed's popular history claims that one of its most famous individuals, Turbante J.O., may have been sired by an unknown Hanoverian stallion. Turbante J.O. sired over 1678 offspring and is present in about 71% of the male pedigrees. We genotyped Turbante J.O. and 29 registered Mangalarga individuals using a commercially availabl...
Bayless RL, Cooper BL, Sheats MK.Plasma cell-free DNA (cfDNA) is a biomarker of ischemia, systemic inflammation, and mortality in humans with gastrointestinal disease. Cell-free DNA has not been investigated as a biomarker for equine colic, to our knowledge. We hypothesized that cfDNA could be measured accurately in neat equine plasma using a benchtop fluorometer and that plasma cfDNA would be elevated in emergency patients compared to healthy horses. Plasma was obtained from blood collected in Roche DNA stabilizing tubes. We used the Qubit 4 fluorometer and 1× dsDNA HS assay kit to measure cfDNA concentration in neat patien...
Cabral LDR, Sato AP, de Sousa RS, Rossa AP, Sanches AWD, Bortoleto CT, Locatelli Dittrich R.The closely related apicomplexa protozoa, Toxoplasma gondii, Neospora spp., and Sarcocystis neurona, have all been associated with neurological and reproductive diseases in horses. However, there is limited data regarding the presence of these three parasites in equine placental tissues and amniotic fluid. The aim of the present report was to investigate the presence of the DNA of T. gondii, Neospora spp. and S. neurona in placentas and amniotic fluid in mares. Anti-T. gondii, anti- S. neurona and anti- Neospora spp. antibody titers were evaluated in 31 mares in the final third of pregnancy by...
Podstawski P, Samiec M, Skrzyszowska M, Szmatoła T, Semik-Gurgul E, Ropka-Molik K.The equine sarcoid is one of the most common neoplasias in the family. Despite the association of this tumor with the presence of bovine papillomavirus (BPV), the molecular mechanism of this lesion has not been fully understood. The transgenization of equine adult cutaneous fibroblast cells (ACFCs) was accomplished by nucleofection, followed by detection of molecular modifications using high-throughput NGS transcriptome sequencing. The results of the present study confirm that - and -mediated nucleofection strategy significantly affected the transcriptomic alterations, leading to sarcoid-like...
Jaramillo-Morales C, Gomez DE, Renaud D, Arroyo LG.The objectives of this study were to determine the prevalence of S. equi in a horse population in Colombia, to determine the risk factors associated with its detection in the guttural pouches and to report the antimicrobial susceptibility of the isolates. Fifteen farms and 137 horses >6 months of age were enrolled. Sampling was randomly, stratified and proportional to the population size of each farm. The guttural pouch (GP) was swabbed via endoscopic guidance and culture was performed. DNA extraction and conventional PCR were performed in colonies compatibles with S. equi, the PCR products we...
Grillos AS, Roach JM, de Mestre AM, Foote AK, Kinglsey NB, Mienaltowski MJ, Bellone RR.Warmblood Fragile Foal Syndrome Type 1 (WFFS) is an autosomal recessive disorder reported previously only in warmbloods and thought to be caused by a variant in the gene procollagen-lysine,2-oxoglutarate 5-dioxygenase 1 (PLOD1, c.2032G>A, p.Gly678Arg). Given the presentation of this Thoroughbred case, we hypothesised that a similar genetic mechanism caused this phenotype. Objective: To describe the pathological and genetic findings on a foal presenting to a veterinary practice in the UK with skin lesions similar to other Ehlers-Danlos Syndromes, including those documented for warmbloods with W...
Addis A, Canciani E, Campagnol M, Colombo M, Frigerio C, Recupero D, Dellavia C, Morroni M.Different xenogeneic inorganic bone substitutes are currently used as bone grafting materials in oral and maxillo-facial surgery. The aim of the present study was to determine the physicochemical properties and the in vivo performance of an anorganic equine bone (AEB) substitute. AEB is manufactured by applying a process involving heating at >300 °C with the aim of removing all the antigens and the organic components. AEB was structurally characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier-transformed infrared (FT-IR) spectros...
Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Kusano K, Nagata SI.Processed pseudogenes, also known as retrocopy genes, are copies of messenger RNAs that have been reverse transcribed into DNA and inserted into the genome. In this study, we identified 62 processed pseudogene candidates as intron-less genes from whole-genome sequencing (WGS) data of Thoroughbred horses using delly structural variation software. The 62 processed pseudogene candidates were confirmed by PCR amplification of intron-less products. A total of 11 processed pseudogenes were confirmed in the genome of all 23 analysed horses, whereas three processed pseudogenes with structures of ATP11...
Maniego J, Pesko B, Hincks P, Taylor P, Stewart G, Proudman C, Scarth J, Ryder E.The misuse of gene therapy by the introduction of transgenes via plasmid or viral vectors as a doping agent is an increasing concern in human and animal sports, not only in consideration to fair competition but also in potential detrimental effects to welfare. Doping events can be detected by polymerase chain reaction (PCR) amplification of a transgene-specific region of DNA. Quantitative real-time PCR (qPCR) is particularly suited to confirmatory investigations where precise limits of detection can be calculated. To fully validate a qPCR experiment, it is highly desirable to confirm the ident...
Mahlobo-Shwabede SIC, Zishiri OT, Thekisoe OMM, Bakkes D, Bohloa L, Molomo M, Makalo MJR, Mahloane GR, Mtshali MS.A total of 3311 tick specimens were randomly collected from domestic animals including cattle, sheep, goats, horses, donkeys, and dogs from Lesotho districts namely, Berea, Butha-Buthe, Leribe, Mafeteng, Maseru, Mohale's Hoek, Mokhotlong, Qacha's Nek, Quthing and Thaba Tseka. Tick species were identified morphologically and verified by amplification and sequencing of the CO1 and 18S rRNA genes. Nine species were identified under different genera namely, Haemaphysalis elliptica 0.1% (n = 2), Hyalomma rufipes 2.6% (n = 87), Hy. truncatum 1.2% (n = 41), Otobius megnini 13.6% (n = 451), Rh...
Bennett EA, Weber J, Bendhafer W, Champlot S, Peters J, Schwartz GM, Grange T, Geigl EM.Before the introduction of domestic horses in Mesopotamia in the late third millennium BCE, contemporary cuneiform tablets and seals document intentional breeding of highly valued equids called kungas for use in diplomacy, ceremony, and warfare. Their precise zoological classification, however, has never been conclusively determined. Morphometric analysis of equids uncovered in rich Early Bronze Age burials at Umm el-Marra, Syria, placed them beyond the ranges reported for other known equid species. We sequenced the genomes of one of these ~4500-year-old equids, together with an ~11,000-year-o...
Wolfsberger WW, Ayala NM, Castro-Marquez SO, Irizarry-Negron VM, Potapchuk A, Shchubelka K, Potish L, Majeske AJ, Oliver LF, Lameiro AD....Since the first Spanish settlers brought horses to America centuries ago, several local varieties and breeds have been established in the New World. These were generally a consequence of the admixture of the different breeds arriving from Europe. In some instances, local horses have been selectively bred for specific traits, such as appearance, endurance, strength, and gait. We looked at the genetics of two breeds, the Puerto Rican Non-Purebred (PRNPB) (also known as the "Criollo") horses and the Puerto Rican Paso Fino (PRPF), from the Caribbean Island of Puerto Rico. While it is reasonable ...
Horvath S, Haghani A, Peng S, Hales EN, Zoller JA, Raj K, Larison B, Robeck TR, Petersen JL, Bellone RR, Finno CJ.Cytosine methylation patterns have not yet been thoroughly studied in horses. Here, we profile n = 333 samples from 42 horse tissue types at loci that are highly conserved between mammalian species using a custom array (HorvathMammalMethylChip40). Using the blood and liver tissues from horses, we develop five epigenetic aging clocks: a multi-tissue clock, a blood clock, a liver clock and two dual-species clocks that apply to both horses and humans. In addition, using blood methylation data from three additional equid species (plains zebra, Grevy's zebras and Somali asses), we develop anoth...
Bergmann W, de Lest CV, Plomp S, Vernooij JCM, Wijnberg ID, Back W, Gröne A, Delany MW, Caliskan N, Tryfonidou MA, Grinwis GCM.Gross morphology of healthy and degenerated intervertebral discs (IVDs) is largely similar in horses as in dogs and humans. For further comparison, the biochemical composition and the histological and biochemical changes with age and degeneration were analyzed in 41 warmblood horses. From 33 horses, 139 discs and 2 fetal vertebral columns were evaluated and scored histologically. From 13 horses, 73 IVDs were assessed for hydration, DNA, glycosaminoglycans, total collagen, hydroxyl-lysyl-pyridinoline, hydroxylysine, and advanced glycation end-product (AGE) content. From 7 horses, 20 discs were ...
Abdullah HHAM, Aboelsoued D, Farag TK, Abdel-Shafy S, Abdel Megeed KN, Parola P, Raoult D, Mediannikov O.Equine vector-borne diseases (EVBDs) are emerging and re-emerging diseases, and most of them are zoonotic. This study aimed to investigate EVBDs in equines and associated arthropods (ticks and flies) from Egypt using molecular analyses, in addition to a preliminary characterization of associated ticks and flies by the matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) and molecular techniques. In this study, 335 blood samples were obtained from equines that appeared to be in good health (320 horses and 15 donkeys) in Cairo and Beni Suef provinces, Egypt. From the same anima...
Vdovina NV, Yuryeva IB.Mezenskaya horse (Mezenka) is Russia's aboriginal breed. It is a domestic selection in the northern territories of Arkhangelsk region. The breed is perfectly adapted to the conditions of the Far North, and has a number of valuable economic and biological qualities. At present, it has a limited gene pool and is bred only in the Mezensky district, where one gene pool-breeding farm is operating and so is a number of basic farms, where selection and breeding activities take place with the breed. Due to a small population of Mezen horses, the challenge of preserving its intra-breed diversity is ver...
Esdaile E, Kallenberg A, Avila F, Bellone RR.Coat color is a trait of economic significance in horses. Variants in seven genes have been documented to cause white patterning in horses. Of the 34 variants that have been identified in KIT proto-oncogene, receptor tyrosine kinase (), 27 have only been reported in a single individual or family and thus not all are routinely offered for genetic testing. Therefore, to enable proper use of marker-assisted selection, determining breed specificity for these alleles is warranted. Screening 19 unregistered all-white Shetland ponies for 16 white patterning markers identified 14 individuals whose phe...
Wang L, Unger L, Sharif H, Eriksson S, Gerber V, Rönnberg H.Thymidine kinase 1 (TK1) plays a key role in the synthesis of deoxythymidine triphosphate (dTTP) and is thus important for DNA replication and cell proliferation. The expression of TK1 is highest during S-phase, and it is rapidly degraded after mitosis. In cancer cells, TK1 is upregulated, resulting in leakage of excess TK1 into the blood. Consequently, serum TK1 has been used as a diagnostic and prognostic cancer biomarker, mainly in human medicine. The aims of this work were to characterize equine TK1 and to evaluate its suitability as a serum biomarker for equine lymphoma. Results: Equine T...
Liu X, Zhang Y, Liu W, Li Y, Pan J, Pu Y, Han J, Orlando L, Ma Y, Jiang L.Chinese ponies are endemic to the mountainous areas of southwestern China and were first reported in the archaeological record at the Royal Tomb of Zhongshan King, Mancheng, dated to approximately ∼2,100 YBP. Previous work has started uncovering the genetic basis of size variation in western ponies and horses, revealing a limited number of loci, including HMGA2,LCORL/NCAPG,ZFAT, and LASP1. Whether the same genetic pathways also drive the small body size of Chinese ponies, which show striking anatomical differences to Shetland ponies, remains unclear. To test this, we combined whole-genome se...
The Journal of heredityDecember 12, 2021
Volume 113, Issue 3 238-247 doi: 10.1093/jhered/esab070
Esdaile E, Avila F, Bellone RR.American Standardbreds were developed as a harness racing horse breed. The United States Trotting Association closed the studbook in 1973 and implemented a book size cap in 2009. This study aimed to investigate genetic diversity in the American Standardbred after the studbook cap was introduced using short tandem repeats (STRs) and single-nucleotide polymorphisms (SNPs). Sixteen STRs from horses foaled from 2010 to 2015 and their sires and dams (n = 50 621) were utilized to examine allelic richness (Ar), expected heterozygosity (HE), observed heterozygosity (HO), unbiased heterozygosity (HU), ...
Murchie TJ, Monteath AJ, Mahony ME, Long GS, Cocker S, Sadoway T, Karpinski E, Zazula G, MacPhee RDE, Froese D, Poinar HN.The temporal and spatial coarseness of megafaunal fossil records complicates attempts to to disentangle the relative impacts of climate change, ecosystem restructuring, and human activities associated with the Late Quaternary extinctions. Advances in the extraction and identification of ancient DNA that was shed into the environment and preserved for millennia in sediment now provides a way to augment discontinuous palaeontological assemblages. Here, we present a 30,000-year sedimentary ancient DNA (sedaDNA) record derived from loessal permafrost silts in the Klondike region of Yukon, Canada. ...
Atsenova N, Palova N, Mehandjyiski I, Neov B, Radoslavov G, Hristov P.The question about the time and the place of horse domestication, a process which had a profound impact on the progress of mankind, is disputable. According to the most widely accepted hypothesis, the earliest domestication of the horse happened in the western parts of the Eurasian steppes, between the Northern Black Sea region and present-day Kazakhstan and Turkmenistan. It seems that it occurred not earlier than the first half and most probably during the middle (even the last third) of the fourth millennium BC (from ∼ 5.5 kya). The next steps of large-scale horse breeding occurred almost ...
Kinoshita Y, Kakoi H, Ishige T, Yamanaka T, Niwa H, Uchida-Fujii E, Nukada T, Ueno T.Taylorella equigenitalis causes contagious equine metritis. Here we compared seven nucleic acid amplification tests for T. equigenitalis to select a rapid and reliable diagnostic method. The 95% detection limits of each assay varied greatly: real-time PCR had the lowest detection limit (0.77 fg/reaction); those of some of the conventional PCRs (cPCRs) were >100 fg/reaction. In experimentally infected samples, real-time PCR and semi-nested PCR showed the highest positive numbers (33 out of 42 samples), but two of the cPCRs detected only 2 and 7 positive results. Our results indicate that the us...
Ribeiro DSC, Martins AV, Lobão LF, Ribeiro MS, Palmer JPS, Corrêa LL, Uchôa CMA, da Silva S, Meireles MV, Amendoeira MRR, Barbosa ADS.An analysis was made of the frequency of Cryptosporidium spp. in fecal samples from horses raised on farms in the Teresópolis city, state of Rio de Janeiro, Brazil, and the risk factors that favored this infection. Between 2019 and 2020, 314 samples of equine feces were collected, 287 of which came from English Thoroughbred horses and 27 from ponies. Information on the horses and their management were retrieved from a stud book and forms filled out by trainers. The fecal samples were subjected to macroscopic analysis, modified Sheather's and Lutz parasitological techniques, safranin staining,...
Leon A, Richard E, Fortier C, Laugier C, Fortier G, Pronost S.Abortion, stillbirth and neonatal death are major causes of equine mortality and cause severe economic loss to the equine industry. The present study was based on a complete necropsy protocol associated with classical microbiological examinations and molecular biology on 407 cases of abortion, stillbirths and neonate death. Based on this retrospective survey, "less common" abortive infectious agents were characterised by molecular tools in nine independent cases of abortion or neonate mortality. Among others, Chlamydophila abortus (1 case), Coxiella burnetii (6 cases) and Neospora caninum (3 c...
Wang T, Shi X, Liu Z, Ren W, Wang X, Huang B, Kou X, Liang H, Wang C, Chai W.Several studies have shown the association between the ligand-dependent nuclear receptor compression-like protein (LCORL) gene and body size in horses, pigs and donkeys. Based on previous studies, the LCORL gene was hypothesized to be associated with growth traits and hide weight in Dezhou donkeys. In this study, we aimed to reveal the variation of the LCORL gene in the Dezhou donkey and explore whether the gene is associated with hide weight and body size. In this study, genetic polymorphisms in the LCORL gene of the Dezhou donkey were studied using targeted sequencing technology, and single ...
Lunn DP, Soboll G, Schram BR, Quass J, McGregor MW, Drape RJ, Macklin MD, McCabe DE, Swain WF, Olsen CW.Equine influenza virus infection remains one of the most important infectious diseases of the horse, yet current vaccines offer only limited protection. The equine immune response to natural influenza virus infection results in long-term protective immunity, and is characterized by mucosal IgA and serum IgGa and IgGb antibody responses. DNA vaccination offers a radical alternative to conventional vaccines, with the potential to generate the same protective immune responses seen following viral infection. Antigen-specific antibody isotype responses in serum and mucosal secretions were studied i...
Marklund S, Chaudhary R, Marklund L, Sandberg K, Andersson L.The hypervariable D-loop region of mitochondrial DNA (mtDNA) was amplified with the polymerase chain reaction using total horse DNA samples. Analysis of single strand conformation polymorphism (SSCP) of denatured amplification products was carried out by native polyacrylamide (8%) gel electrophoresis followed by silver staining. As many as 15 distinct SSCP variants were revealed when screening a total of 78 maternally unrelated horses representing five different breeds. All breeds showed a high degree of polymorphism and the estimated probability (PImt) that two maternally unrelated individual...
Steinman A, Zimmerman T, Klement E, Lensky IM, Berlin D, Gottlieb Y, Baneth G.The prevalence of Theileria equi infection as well as the environmental and demographic risk factors for infection was studied in 590 healthy horses from 46 farms in Israel. The prevalence of T. equi DNA was assessed using a polymerase chain reaction for a segment of the Theileria 18S rRNA gene. The overall prevalence was 26.4% (156/590). There was a significant geographical variation in the prevalence of T. equi infection, ranging from 9.3% (25/270) in the central lowlands to 81.7% (49/60) in the Golan Heights. The prevalence of T. equi infection was found to be significantly associated with ...
van Herwerden L, Gasser RB, Blair D.This study investigated sequence heterogeneity in the first internal transcribed spacer (ITS-1) of ribosomal DNA within and among species and strains of Echinococcus. Different ITS-1 sequence variants exist in Echinococcus granulosus and Echinococcus multilocularis, which represent at least four evolutionary lineages: (1) a sheep strain-lineage of E. granulosus, (2) a sister lineage of a cervid and camel E. granulosus ITS-1 variants, (3) a lineage including the ITS-1 variants representing horse, bovine and camel strains of E. granulosus, as well as variants from E. multilocularis, Echinococcus...
Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Kusano K, Nagata SI.The Thoroughbred breed was formed by crossing Oriental horse breeds and British native horses and is currently used in horseracing worldwide. In this study, we constructed a single-nucleotide variant (SNV) database using data from 101 Thoroughbred racehorses. Whole genome sequencing (WGS) revealed 11,570,312 and 602,756 SNVs in autosomal (1-31) and X chromosomes, respectively, yielding a total of 12,173,068 SNVs. About 6.9% of identified SNVs were rare variants observed only in one allele in 101 horses. The number of SNVs detected in individual horses ranged from 4.8 to 5.3 million. Individual...
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...
Garner DL, Evans KM, Seidel GE.The sex of mammalian offspring can be predetermined by flow sorting relatively pure living populations of X- and Y-chromosome-bearing sperm. This method is based on precise staining of the DNA of sperm with the nucleic acid-specific fluorophore, Hoechst 33342, to differentiate between the subpopulations of X- and Y-sperm. The fluorescently stained sperm are then sex-sorted using a specialized high speed sorter, MoFlo(®) SX XDP, and collected into biologically supportive media prior to reconcentration and cryopreservation in numbers adequate for use with artificial insemination for some specie...
Vo AT, van Duijkeren E, Fluit AC, Gaastra W.To investigate the genotypic resistance of integron-carrying Salmonella Typhimurium isolates from horses and their genetic relationship. Methods: Sixty-one Salmonella isolates were screened for the presence of class 1 integrons by PCR. The gene cassettes of integron-positive isolates were detected by PCR, restriction fragment length polymorphism typing, and sequencing. The potential for the transfer of resistance determinants was investigated by conjugation experiments. The presence of Salmonella genomic island 1 (SGI1) or its variants was studied by PCR and nucleotide sequencing. PFGE was use...
Staiger EA, Al Abri MA, Pflug KM, Kalla SE, Ainsworth DM, Miller D, Raudsepp T, Sutter NB, Brooks SA.Conformation has long been a driving force in horse selection and breed creation as a predictor for performance. The Tennessee Walking Horse (TWH) ranges in size from 1.5 to 1.7 m and is often used as a trail, show, and pleasure horse. To investigate the contribution of genetics to body conformation in the TWH, we collected DNA samples, body measurements, and gait/training information from 282 individuals. We analyzed the 32 body measures with a principal component analysis. Principal component (PC)1 captured 28.5% of the trait variance, while PC2 comprised just 9.5% and PC3 6.4% of trait vari...
Binns MM, Holmes NG, Holliman A, Scott AM.Six new horse microsatellite loci were identified by sequencing M13 clones containing horse genomic inserts which gave positive signals when probed with a CA/GT repeat probe. Oligonucleotide primer pairs were synthesized for these loci and for two previously described horse microsatellites, HTG4 and HTG6. Polymerase chain reaction assays were then carried out on a panel of 20 different unrelated Thoroughbred horse DNAs. DNAs from eight cases of double covering which could not be solved by conventional blood typing were also examined. Several of the loci amplified were found to be polymorphic a...
Fernández D, González-Baradat B, Eleizalde M, González-Marcano E, Perrone T, Mendoza M.Trypanosoma evansi is the causative agent of equine trypanosomosis, disease that affects horse's productivity and health. Parasitological and molecular methods are mostly used to detect the infection. The aim of this work was evaluate PCR sensitivity to detect T. evansi using the primers 21/22-mer, ITS1, ESAG 6/7 and TBR 1/2 designed from repetitive (multicopies) genomic sequences. The results were compare with two parasitological tests in mice, micro-haematocrite centrifugation technique and direct microscopic examination. The results shows (a) that the minimum amount of DNA from blood of hig...
Jakobsen L, Bortolaia V, Bielak E, Moodley A, Olsen SS, Hansen DS, Frimodt-Møller N, Guardabassi L, Hasman H.CTX-M-1 is a common extended-spectrum β-lactamase (ESBL) in Escherichia coli from animals and is often detected among human clinical isolates. The objective of this study was to investigate the epidemiological relationship between CTX-M-1-producing E. coli isolated from patients and animals in Denmark between 2006 and 2010. In total, 65 CTX-M-1-producing isolates from patients (n=22), pigs (n=21), cattle (n=4), organic poultry layers (n=3) and horses (n=15) were typed by pulsed-field gel electrophoresis (PFGE). Plasmids harbouring bla were characterised by S1 PFGE, PCR-based replicon typing, ...
Pessôa LVF, Pires PRL, Del Collado M, Pieri NCG, Recchia K, Souza AF, Perecin F, da Silveira JC, de Andrade AFC, Ambrosio CE, Bressan FF....Pluripotent stem cells are believed to have greater clinical potential than mesenchymal stem cells due to their ability to differentiate into almost any cell type of an organism, and since 2006, the generation of patient-specific induced pluripotent stem cells (iPSCs) has become possible in multiple species. Objective: We hypothesize that different cell types respond differently to the reprogramming process; thus, the goals of this study were to isolate and characterize equine adult and fetal cells and induce these cells to pluripotency for future regenerative and translational purposes. Metho...
Hasegaw T, Sato F, Ishida N, Fukushima Y, Mukoyama H.A quick method for sex determination of horses was developed. Simultaneous amplification of the equine sex-determining region of the Y chromosome gene (SRY) and amelogenin gene (AMEL) accomplished the determination of the presence of both the Y chromosome and SRY gene. In agarose gel electrophoresis, a normal stallion showed 1 SRY band and 3 AMEL (AMELX, AMELY, and AMELX/AMELY heteroduplex) bands, and a normal mare showed a single AMELX band. In XY-mares, 3 AMEL bands were detected as in a normal stallion, but no SRY band. The present method enables a quick diagnosis for XY-mare prior to cytog...
Salim B, Bakheit MA, Kamau J, Sugimoto C.This is a cross-sectional molecular epidemiological study on equine piroplasmosis (EP) affecting horses and donkeys in the Sudan. The study evaluated 499 samples from geographically distinct regions in eastern, central and western parts of the country. PCR amplification of the 18S rRNA gene of both Thelieria equi and Babesia caballi was carried out. Horses from all sampled areas were found positive to T. equi DNA but no B. caballi was detected. Absence of B. caballi infection was confirmed by another PCR targeting the B. caballi 48-kDa merozoite antigen. The overall prevalence was found to be ...
The Journal of heredityDecember 28, 2018
Volume 110, Issue 2 173-182 doi: 10.1093/jhered/esy061
Sadeghi R, Moradi-Shahrbabak M, Miraei Ashtiani SR, Schlamp F, Cosgrove EJ, Antczak DF.The principal aims of this study were to explore genetic diversity and genome-wide selection signatures in Persian Arabian horses and to determine genetic relationship of Persian Arabians with other Iranian horse breeds. We evaluated 71 horses from 8 matrilineal strains tracing to 47 mares from the mid to late 19th century, using the equine 670k single nucleotide polymorphism (SNP) BeadChip. Mean observed and expected heterozygosity were (0.43) and (0.45), respectively, average inbreeding measures (inbreeding estimates based on runs of homozygosity and pedigree information) were low, indicatin...
Morita H, Shiratori C, Murakami M, Takami H, Toh H, Kato Y, Nakajima F, Takagi M, Akita H, Masaoka T, Hattori M.Four bacterial strains, designated ST18(T), HM244, HM250 and DI49, were isolated from the fresh faeces of four thoroughbred horses in Japan. Cells were Gram-positive, strictly anaerobic, catalase-negative, non-spore-forming, non-motile rods that occurred in chains. They were placed in the same subcluster based on 16S rRNA gene sequence analysis, phenotypic characteristics and levels of DNA-DNA relatedness. Their DNA G+C content ranged from 36 to 38 mol%. Lactobacillus catenaformis, Lactobacillus vitulinus and Catenibacterium mitsuokai belong to cluster XVII of the Clostridium subphylum. Strain...
Equine sarcoids are benign fibroblastic skin tumours that are recognized throughout the world. Infection with bovine papillomavirus (BPV) types 1 and 2 has been implicated as a major factor in disease development; however, the cellular mechanisms underlying fibroblast transformation remain poorly defined. The present study further characterizes aspects of the association with BPV in 15 equine sarcoids. BPV DNA was demonstrated in 12/15 tumours collected from different areas of Italy. Nine of these 12 tumours expressed the BPV oncoproteins E5 and E7, but these oncoproteins were not expressed by...
Whetter L, Archambault D, Perry S, Gazit A, Coggins L, Yaniv A, Clabough D, Dahlberg J, Fuller F, Tronick S.A full-length molecular clone of equine infectious anemia virus (EIAV) was isolated from a persistently infected canine fetal thymus cell line (Cf2Th). Upon transfection of equine dermis cells, the clone, designated CL22, yielded infectious EIAV particles (CL22-V) that replicated in vitro in both Cf2Th cells and an equine dermis cell strain. Horses infected with CL22-V developed an antibody response to viral proteins and possessed viral DNA in peripheral blood mononuclear cells, as determined by polymerase chain reaction assays. In addition, horses infected with CL22-V became persistently infe...
Shilton CA, Kahler A, Davis BW, Crabtree JR, Crowhurst J, McGladdery AJ, Wathes DC, Raudsepp T, de Mestre AM.The first 8 weeks of pregnancy is a critical time, with the majority of pregnancy losses occurring during this period. Abnormal chromosome number (aneuploidy) is a common finding in human miscarriage, yet is rarely reported in domestic animals. Equine early pregnancy loss (EPL) has no diagnosis in over 80% of cases. The aim of this study was to characterise aneuploidies associated with equine EPL. Genomic DNA from clinical cases of spontaneous miscarriage (EPLs; 14-65 days of gestation) and healthy control placentae (various gestational ages) were assessed using a high density genotyping arr...
Malekifard F, Tavassoli M, Yakhchali M, Darvishzadeh R.Equine piroplasmosis is a severe disease of horses caused by the intra-erythrocyte protozoan, Theileria equi and Babesia caballi. The aim of this study was to identify equine piroplasmosis based on molecular and morphometrical features in horses in suburb of Urmia, West Azerbaijan province, Iran. From April to September 2011, a total number of 240 blood samples were collected randomly from horses of 25 villages. The specimens were transferred to the laboratory and the blood smears stained with Geimsa, and the morphological and biometrical data of parasite in any infected erythrocyte were consi...
Abdullaev ZKh, Bodrova ME, Chernyak BV, Dolgikh DA, Kluck RM, Pereverzev MO, Arseniev AS, Efremov RG, Kirpichnikov MP, Mokhova EN, Newmeyer DD....A cytochrome c mutant lacking apoptogenic function but competent in electron transfer and antioxidant activities has been constructed. To this end, mutant species of horse and yeast cytochromes c with substitutions in the N-terminal alpha-helix or position 72 were obtained. It was found that yeast cytochrome c was much less effective than the horse protein in activating respiration of rat liver mitoplasts deficient in endogenous cytochrome c as well as in inhibition of H(2)O(2) production by the initial segment of the respiratory chain of intact rat heart mitochondria. The major role in the di...
Plummer G, Goodheart CR, Studdert MJ.Equine herpesviruses with a deoxyribonucleic acid density of 1.716 to 1.717 g/cm(3) were compared with one another by the plaque-reduction test and by the rate of development of cytopathic effect as indicated by plaque size in rabbit kidney cultures. Of the 19 isolates studied, the 9 which had already been tentatively labeled equine abortion viruses were serologically similar to one another; each of them grew more quickly than did any of the other 10 isolates although the mean plaque sizes formed a series of gradations with no clear hiatus which would permit the unequivocal delineation of the ...
Astakhova NM, Perelygin AA, Zharkikh AA, Lear TL, Coleman SJ, MacLeod JN, Brinton MA.Toll-like receptors 3, 7, and 8 (TLR3, TLR7, and TLR8) were studied in the genomes of the domestic horse and several other mammals. The messenger RNA sequences and exon/intron structures of these TLR genes were determined. An equine bacterial artificial chromosome clone containing the TLR3 gene was assigned by fluorescent in situ hybridization to the horse chromosomal location ECA27q16-q17 and this map location was confirmed using an equine radiation hybrid panel. Direct sequencing revealed 13 single-nucleotide polymorphisms in the coding regions of the equine TLR 3, 7, and 8 genes. Of these p...
Pereyra-Bonnet F, Fernández-Martín R, Olivera R, Jarazo J, Vichera G, Gibbons A, Salamone D.Transgenesis is an essential tool in many biotechnological applications. Intracytoplasmic sperm injection (ICSI)-mediated gene transfer is a powerful technique to obtain transgenic pups; however, most domestic animal embryos do not develop properly after ICSI. An additional step in the protocol, namely assistance by haploid chemical activation, permits the use of ICSI-mediated gene transfer to generate transgenic preimplantation embryos in a wide range of domestic species, including ovine, porcine, feline, equine and bovine. In the present study, spermatozoa from five species were coincubated ...
Metzger J, Rau J, Naccache F, Bas Conn L, Lindgren G, Distl O.Miniature size in horses represents an extreme reduction of withers height that originated after domestication. In some breeds, it is a highly desired trait representing a breed- or subtype-specific feature. The genomic changes that emerged due to strong-targeted selection towards this distinct type remain unclear. Results: Comparisons of whole-genome sequencing data from two Miniature Shetland ponies and one standard-sized Shetland pony, performed to elucidate genetic determinants for miniature size, revealed four synergistic variants, limiting withers height to 34.25 in. (87 cm). Runs of h...
van der Harst MR, Brama PA, van de Lest CH, Kiers GH, DeGroot J, van Weeren PR.In articular joints, the forces generated by locomotion are absorbed by the whole of cartilage, subchondral bone and underlying trabecular bone. The objective of this study is to test the hypothesis that regional differences in joint loading are related to clear and interrelated differences in the composition of the extracellular matrix (ECM) of all three weight-bearing constituents. Methods: Cartilage, subchondral- and trabecular bone samples from two differently loaded sites (site 1, dorsal joint margin; site 2, central area) of the proximal articular surface of 30 macroscopically normal equ...
Librado P, Orlando L.The equid family contains only one single extant genus, , including seven living species grouped into horses on the one hand and zebras and asses on the other. In contrast, the equine fossil record shows that an extraordinarily richer diversity existed in the past and provides multiple examples of a highly dynamic evolution punctuated by several waves of explosive radiations and extinctions, cross-continental migrations, and local adaptations. In recent years, genomic technologies have provided new analytical solutions that have enhanced our understanding of equine evolution, including the spe...
