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.
Holl HM, Vanhnasy J, Everts RE, Hoefs-Martin K, Cook D, Brooks SA, Carpenter ML, Bustamante CD, Lafayette C.Genetic markers are important resources for individual identification and parentage assessment. Although short tandem repeats (STRs) have been the traditional DNA marker, technological advances have led to single nucleotide polymorphisms (SNPs) becoming an attractive alternative. SNPs can be highly multiplexed and automatically scored, which allows for easier standardization and sharing among laboratories. Equine parentage is currently assessed using STRs. We obtained a publicly available SNP dataset of 729 horses representing 32 diverse breeds. A proposed set of 101 SNPs was analyzed for DNA ...
Seeber PA, Soilemetzidou SE, East ML, Walzer C, Greenwood AD.Direct collection of samples from wildlife can be difficult and sometimes impossible. Non-invasive remote sampling for the purpose of DNA extraction is a potential tool for monitoring the presence of wildlife at the individual level, and for identifying the pathogens shed by wildlife. Equine herpesviruses (EHV) are common pathogens of equids that can be fatal if transmitted to other mammals. Transmission usually occurs by nasal aerosol discharge from virus-shedding individuals. The aim of this study was to validate a simple, non-invasive method to track EHV shedding in zebras and to establish ...
Liu Q, Wang XF, Du C, Lin YZ, Ma J, Wang YH, Zhou JH, Wang X.Integration is an important feature of retroviruses and retrovirus-based therapeutic transfection vectors. The non-primate lentivirus equine infectious anaemia virus (EIAV) primarily targets macrophages/monocytes . Investigation of the integration features of EIAV strains, which are adapted to donkey monocyte-derived macrophages (MDMs), is of great interest. In this study, we analysed the integration features of EIAV in equine MDMs during infection. Our previously published integration sites (IS) for EIAV in fetal equine dermal (FED) cells were also analysed in parallel as references. Sequenc...
Montes-Cortés MG, Fernández-García JL, Martínez-Estéllez MÁH.Equine piroplasmosis is caused by two haemoprotozoan parasites: and . Negative economic impact on international trade has been associated to endemic sites. This is the reason why carrier detection requires reliable diagnostic methods. Various diagnostic modalities can be used alone or in combination including PCR. However, genetic variation of commonly used genes is still of debate. The aim of this research was to sequence the β-tubulin gene of a strain from Spain and to compare it with known β-tubulin sequences. Methods: DNA was isolated from a cryopreserved strain from Spain and acute an...
Usuga A, Rojano BA, Restrepo G.Contribution of seminal plasma proteins to semen freezability has been reported in several species, suggesting these proteins as genetic markers. The aim of this study was to evaluate the relationship between cysteine-rich secretory protein-3 (CRISP-3) and some of its single-nucleotide polymorphisms (SNPs) with post-thawing semen quality in stallions. DNA was obtained from 100 stallions, regions of interest were amplified by polymerase chain reaction and sequenced. Evaluated SNPs within the equine CRISP-3 gene were CRISP3c.+199A>G (SNP1), CRISP3c.+566C>A (SNP2), CRISP3c.+622G>A (SNP3)...
Ianella P, Albuquerque MSM, Paiva SR, Egito AA, Almeida LD, Sereno FTPS, Carvalho LFR, Mariante AS, McManus CM.The first horses were brought to Brazil by the colonizers after 1534. Over the centuries, these animals evolved and adapted to local environmental conditions usually unsuitable for exotic breeds, thereby originating locally adapted Brazilian breeds. The present work represents the first description of maternal genetic diversity in these horse breeds based on D-loop sequences. A D-Loop HSV-I fragment of 252 bp, from 141 horses belonging to ten Brazilian breeds / genetic groups (locally adapted and specialized breeds) were analysed. Thirty-five different haplotypes belonging to 18 haplogroups we...
Hudson W.Egyptian Arabian horses have been maintained in a state of genetic isolation for over a hundred years. There is only limited genetic proof that the studbook records of female lines of Egyptian Arabian pedigrees are reliable. This study characterized the mitochondrial DNA (mtDNA) signatures of 126 horses representing 14 matrilines in the Egyptian Agricultural Organization (EAO) horse-breeding program. Results: Analysis of the whole D-loop sequence yielded additional information compared to hypervariable region-1 (HVR1) analysis alone, with 42 polymorphic sites representing ten haplotypes compar...
Balmer P, Bauer A, Pujar S, McGarvey KM, Welle M, Galichet A, Müller EJ, Pruitt KD, Leeb T, Jagannathan V.Keratins represent a large protein family with essential structural and functional roles in epithelial cells of skin, hair follicles, and other organs. During evolution the genes encoding keratins have undergone multiple rounds of duplication and humans have two clusters with a total of 55 functional keratin genes in their genomes. Due to the high similarity between different keratin paralogs and species-specific differences in gene content, the currently available keratin gene annotation in species with draft genome assemblies such as dog and horse is still imperfect. We compared the National...
Linder KE, Bizikova P, Luff J, Zhou D, Yuan H, Breuhaus B, Nelson E, Mackay R.Currently, seven equine papillomaviruses (PV) are known and are associated with one of three different and distinct clinical presentations. Objective: To report the clinical, histopathological and immunohistochemical findings in horses with generalized papillomatosis associated with a novel equine PV, Equus caballus papillomavirus 8 (EcPV8). Methods: Three client-owned quarter horses. Methods: Case report, retrospective. Results: Dozens to thousands of papillomas involved the axilla, inguinal area and proximal limbs as well as the ventral and lateral neck, thorax and abdomen. Lesions were some...
Barrón-Ortiz CI, Rodrigues AT, Theodor JM, Kooyman BP, Yang DY, Speller CF.Horses were a dominant component of North American Pleistocene land mammal communities and their remains are well represented in the fossil record. Despite the abundant material available for study, there is still considerable disagreement over the number of species of Equus that inhabited the different regions of the continent and on their taxonomic nomenclature. In this study, we investigated cheek tooth morphology and ancient mtDNA of late Pleistocene Equus specimens from the Western Interior of North America, with the objective of clarifying the species that lived in this region prior to t...
Dougal K, Harris PA, Girdwood SE, Creevey CJ, Curtis GC, Barfoot CF, Argo CM, Newbold CJ.Twelve mature (aged 5-16 years) horses and ponies of mixed breed and type were fed restricted (1.25% BM Dry matter) quantities of one of two fiber based diets formulated to be iso-caloric. Diet 1 comprised of 0.8% body mass (BM) of chaff based complete feed plus 0.45% BM low energy grass hay (the same hay used for both diets). Diet 2 comprised 0.1% BM of a nutrient balancer plus 1.15% BM grass hay. Fecal samples were collected at week 10 and week 16. DNA was extracted and the V1-V2 regions of 16SrDNA were 454-pyrosequenced to investigate the bacterial microbiome of the horse. The two most abun...
Gao JF, Liu GH, Duan H, Gao Y, Zhang Y, Chang QC, Fang M, Wang CR.Triodontophorus serratus and Triodontophorus nipponicus are two of the most common nematodes inhabiting in the large intestine of horse. In the present study, the complete mitochondrial (mt) genome sequences of T. serratus and T. nipponicus have been determined. The mt genomes of T. serratus and T. nipponicus are circular molecules with 13,794 bp and 13,701 bp in size, respectively. These circular mt genomes encode 36 genes, including 12 protein-coding genes, two rRNA genes and 22 tRNA genes. All of these genes are transcribed in the same direction and gene arrangements are consistent with...
Mack M, Kowalski E, Grahn R, Bras D, Penedo MCT, Bellone R.A unique eye color, called tiger-eye, segregates in the Puerto Rican Paso Fino (PRPF) horse breed and is characterized by a bright yellow, amber, or orange iris. Pedigree analysis identified a simple autosomal recessive mode of inheritance for this trait. A genome-wide association study (GWAS) with 24 individuals identified a locus on ECA 1 reaching genome-wide significance ( = 1.32 × 10). This ECA1 locus harbors the candidate gene, (), (), with known roles in pigmentation in humans, mice, and zebrafish. Humans with compound heterozygous mutations in have oculocutaneous albinism (OCA) type...
Gao Y, Zhang Y, Yang X, Qiu JH, Duan H, Xu WW, Chang QC, Wang CR.Equine strongyles, the significant nematode pathogens of horses, are characterized by high quantities and species abundance, but classification of this group of parasitic nematodes is debated. Mitochondrial (mt) genome DNA data are often used to address classification controversies. Thus, the objectives of this study were to determine the complete mt genomes of three Cyathostominae nematode species (, and ) of horses and reconstruct the phylogenetic relationship of Strongylidae with other nematodes in Strongyloidea to test the hypothesis that spp. belong to Cyathostominae using the mt genomes...
Schaefer RJ, Schubert M, Bailey E, Bannasch DL, Barrey E, Bar-Gal GK, Brem G, Brooks SA, Distl O, Fries R, Finno CJ, Gerber V, Haase B, Jagannathan V....To date, genome-scale analyses in the domestic horse have been limited by suboptimal single nucleotide polymorphism (SNP) density and uneven genomic coverage of the current SNP genotyping arrays. The recent availability of whole genome sequences has created the opportunity to develop a next generation, high-density equine SNP array. Using whole genome sequence from 153 individuals representing 24 distinct breeds collated by the equine genomics community, we cataloged over 23 million de novo discovered genetic variants. Leveraging genotype data from individuals with both whole genome sequence, ...
Staiger EA, Almén MS, Promerová M, Brooks S, Cothran EG, Imsland F, Jäderkvist Fegraeus K, Lindgren G, Mehrabani Yeganeh H, Mikko S, Vega-Pla JL....A previous study revealed a strong association between the DMRT3:Ser301STOP mutation in horses and alternate gaits as well as performance in harness racing. Several follow-up studies have confirmed a high frequency of the mutation in gaited horse breeds and an effect on gait quality. The aim of this study was to determine when and where the mutation arose, to identify additional potential causal mutations and to determine the coalescence time for contemporary haplotypes carrying the stop mutation. We utilized sequences from 89 horses representing 26 breeds to identify 102 SNPs encompassing the...
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...
Gibson C, de Ruijter-Villani M, Stout TAE.Placental imprinted genes appear to be sensitive indicators of an inappropriate pre-implantation environment. This study examined the effects of negative uterine asynchrony after embryo transfer (ET) on early horse embryo development, and yolk-sac membrane expression of DNA methyltransferases (DNMTs) and equine specific placental imprinted genes. Methods: Day 8 embryos were transferred to recipient mares on day 8 (synchronous) or day 3 (asynchronous) after ovulation, and conceptuses were recovered 6 or 11 days later (day 14 or 19 of development). Results: Day 14 conceptuses recovered from an a...
Othman OE, Mahrous KF, Shafey HI.Horses are one of the early domesticated animals in the world that changed societies and civilizations on a continent-wide scale. Due to the rare information about the genetic characterization of different horse populations in Egypt, this study aimed to identify the genetic biodiversity and relationships between four horse populations reared in Egypt. Genomic DNA was extracted and mtDNA region was amplified using polymerase chain reaction (PCR). The alignment of 384-bp amplified fragments showed the presence of 41 polymorphic sites resulting in 29 haplotypes which their sequences were submitte...
Wallner B, Palmieri N, Vogl C, Rigler D, Bozlak E, Druml T, Jagannathan V, Leeb T, Fries R, Tetens J, Thaller G, Metzger J, Distl O, Lindgren G....The Y chromosome directly reflects male genealogies, but the extremely low Y chromosome sequence diversity in horses has prevented the reconstruction of stallion genealogies [1, 2]. Here, we resolve the first Y chromosome genealogy of modern horses by screening 1.46 Mb of the male-specific region of the Y chromosome (MSY) in 52 horses from 21 breeds. Based on highly accurate pedigree data, we estimated the de novo mutation rate of the horse MSY and showed that various modern horse Y chromosome lineages split much later than the domestication of the species. Apart from few private northern Euro...
Dimsoski P.To show that application of the polymerase chain reaction (PCR) method modified for amplification of a low-copy number DNA samples, ie, the isolation of PCR products (IPCRp), would represent improvement in obtaining genotypes from a fecal DNA compared with previously used genotyping methods. Methods: The DNA from the horse fecal matter was extracted by modified Qiagen DNA Stool Mini Kit protocol. Following the extraction, the DNA genotypes from fecal samples were obtained by the most powerful PCR amplification method, the IPCRp. The IPCRp-based multiplex kit amplified biotin-labeled strands we...
Plumlee Q, Meason-Smith C, Dieterly A, Gomez G, Porter BF, Rodrigues Hoffmann A.Many previously unrecognized fungi are emerging as potential pathogens. One such group is dematiaceous fungi of the Chaetomiaceae family (phylum Ascomycota, class Sordariomycetes). These fungi are rare causes of opportunistic, neurotropic phaeohyphomycosis in humans but are not known to cause similar infections in animals. The aims of this study were to investigate equine hyphal mycotic encephalitis, characterize key histopathologic features, and classify causative organisms with molecular diagnostic techniques. Seven cases were evaluated by histopathology. Panfungal PCR targeting the ribosoma...
Adamska M, Skotarczak B.The purpose of this study was to detect piroplasms, which are pathogens of veterinary and zoonotic importance in ticks, that were collected from ponies and field vegetation and to determine the role of Shetland ponies as potential reservoir hosts for piroplasms. A total of 1737 feeding and 371 questing Ixodes ricinus collected from horses or vegetation were tested for the presence of Babesia and Theileria DNA. Piroplasm 18S rRNA gene amplification was conducted, and the obtained amplicons were sequenced. Babesia DNA was detected in only three ticks (one tick collected from a pony and two colle...
Charbonneau ARL, Forman OP, Cain AK, Newland G, Robinson C, Boursnell M, Parkhill J, Leigh JA, Maskell DJ, Waller AS.Utilising next generation sequencing to interrogate saturated bacterial mutant libraries provides unprecedented information for the assignment of genome-wide gene essentiality. Exposure of saturated mutant libraries to specific conditions and subsequent sequencing can be exploited to uncover gene essentiality relevant to the condition. Here we present a barcoded transposon directed insertion-site sequencing (TraDIS) system to define an essential gene list for Streptococcus equi subsp. equi, the causative agent of strangles in horses, for the first time. The gene essentiality data for this grou...
Wach-Gygax L, Burger D, Malama E, Bollwein H, Fleisch A, Jeannerat E, Thomas S, Schuler G, Janett F.In this study annual fluctuations of DNA fragmentation and quality of cold-stored equine sperm were evaluated. Ejaculates were collected weekly during one year from 15 stallions. Ejaculate volume, sperm concentration and total sperm count were determined and semen was then extended and cold-stored for 48 h. Sperm motility was evaluated by CASA before and after 24 as well as 48 h of cold storage. In addition, the percentages of sperm with intact plasma membrane and acrosome (PMAI %) and with low intracellular Ca2+ level were determined in cold-stored semen (24 h, 48 h). SCSA™ was performe...
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...
Mirajkar NS, Kelley MR, Gebhart CJ.Reported herein is the draft genome sequence of equine-origin Lawsonia intracellularis strain E40504, an obligate intracellular bacterium and the etiological agent of equine proliferative enteropathy. The 1.69-Mb draft genome sequence includes 1,380 protein-coding genes and 49 RNA genes, and it lacks a genomic island reported in swine-origin L. intracellularis strain PHE/MN1-00.
Bellone RR, Liu J, Petersen JL, Mack M, Singer-Berk M, Drögemüller C, Malvick J, Wallner B, Brem G, Penedo MC, Lassaline M.Squamous cell carcinoma (SCC) is the most common cancer of the equine eye, frequently originating at the limbus, with the potential to invade the cornea, cause visual impairment, and result in loss of the eye. Several breeds of horses have a high occurrence of limbal SCC implicating a genetic basis for limbal SCC predisposition. Pedigree analysis in the Haflinger breed supports a simple recessive mode of inheritance and a genome-wide association study (N = 23) identified a 1.5 Mb locus on ECA12 significantly associated with limbal SCC (Pcorrected = 0.04). Sequencing the most physiologicall...
Sykora S, Jindra C, Hofer M, Steinborn R, Brandt S.In horses, squamous cell carcinomas (SCC) commonly affect the external genitals. There is growing evidence that equine papillomavirus type 2 (EcPV2) infection promotes disease development. To assess the possible association of EcPV2 with equine SCCs of the head (HSCC), 15 HSCC DNA samples were screened by E6/E7, E2, and LCR PCR and amplicons were analysed for sequence variations. The physical form of EcPV2 in HSCC, genital lesions, and smegma from horses with SCC was then addressed using EcPV2 immunocapture PCR (IC/PCR) for detection of virion, and E6 vs. E2 qPCR to investigate possible integr...
Equine lentivirus receptor-1 (ELR1) has been characterized as the specific functional receptor that mediates equine infectious anemia virus (EIAV) entrance to horse macrophages. This receptor is tumor necrosis factor receptor superfamily member 14 (TNFRSF14). The aim of this study was to investigate the occurrence of allelic variants in the coding sequence of equine TNFRSF14 gene by screening for single-nucleotide polymorphisms (SNPs) in different equine populations. Forty seven horse samples were randomly selected from a reservoir of EIAV-seropositive and seronegative samples collected from d...
Wills JM, Watson G, Lusher M, Mair TS, Wood D, Richmond SJ.This paper describes the isolation and characterisation of a strain of Chlamydia psittaci obtained from a nasal swab taken from a horse with serous nasal discharge. Initial isolation was achieved in cycloheximide-treated McCoy cell monolayers. Chlamydial inclusions stained by immunofluorescence either with a rabbit antiserum raised against C. psittaci or with a monoclonal antibody directed against the genus-specific lipopolysaccharide antigen were single and compact. They did not stain with iodine or with a monoclonal antibody reactive against Chlamydia trachomatis. The agent was re-isolated i...
Dong JB, Zhu W, Cook FR, Goto Y, Horii Y, Haga T.Equine infectious anemia (EIA) has posed a major challenge and caused significant losses to the equine industry worldwide. PCR detection methods have considerable potential as an adjunct to conventional serological diagnostic techniques. However, most published PCR methods, including that recommended by the OIE, were designed using laboratory-adapted virus strains and do not function with field isolates of EIA virus (EIAV). In the present study, a nested PCR assay for detection of EIAV proviral DNA in peripheral blood cells of naturally infected horses was developed. Primer sets were designed ...
Love CC, Brinsko SP, Rigby SL, Thompson JA, Blanchard TL, Varner DD.The relationship between seminal plasma level (0, 10, or 20%) and extender type [Kenney type (EZ-Mixin-CST) or Kenney-modified Tyrodes-KMT] to the susceptibility of sperm DNA to denaturation and sperm motility measures were investigated in cooled (5 degrees C) stallion sperm. Three ejaculates from each of three fertile stallions were collected in an artificial vagina and processed as follows: diluted one part uncentrifuged semen with four parts of extender to a final concentration of 20% seminal plasma in either CST or KMT (20% CST; 20% KMT); diluted to a final concentration of 25 million sper...
Révay T, Villagómez DA, Brewer D, Chenier T, King WA.Genetic sex in mammals is determined by the sex chromosomal composition of the zygote. The X and Y chromosomes are responsible for numerous factors that must work in close concert for the proper development of a healthy sexual phenotype. The role of androgens in case of XY chromosomal constitution is crucial for normal male sex differentiation. The intracellular androgenic action is mediated by the androgen receptor (AR), and its impaired function leads to a myriad of syndromes with severe clinical consequences, most notably androgen insensitivity syndrome and prostate cancer. In this paper, w...
Neuhauser S, Bollwein H, Siuda M, Handler J.The aim of the present study was to evaluate the effect of different freezing procedures on sperm motion, viability, the acrosome status, mitochondrial membrane potential (MMP), intracellular calcium content, and DNA integrity on epididymal stallion sperm. Therefore, the sperm of 10 healthy stallions was harvested by retrograde flushing after testectomy, diluted with a semen extender containing defined milk proteins and a freezing extender containing egg yolk and glycerol and frozen according to 4 different protocols, using a programmable freezer and a floating rack performing a slow (processe...
Bigi D, Perrotta G, Zambonelli P.To understand the origin and genetic diversity of Italian horses, mitochondrial DNA D-loop sequences were generated for 163 horses from seven breeds. Sequence analysis of a 480-bp segment revealed a total of 84 haplotypes with 57 polymorphic sites, indicating multiple maternal origins and high genetic diversity. Comparison of the haplotypes with the equine mtDNA haplotype/haplogroup nomenclature showed a haplogroup distribution in the Italian breeds more similar to that found in the Middle East breeds than in the European breeds, probably due to the economic and cultural relationship with the ...
Fischer NM, Favrot C, Birkmann K, Jackson M, Schwarzwald CC, Müller M, Tobler K, Geisseler M, Lange CE.The DNA of equine papillomavirus type 2 (EcPV2) is consistently found in equine papillomas and squamous cell carcinomas, indicating a causal association of EcPV2 in the pathogenesis of these tumours; however, little is known about the prevalence of this virus. Objective: The aim of this study was to determine the geno- and seroprevalence of EcPV2 in clinically healthy horses in Switzerland. Methods: Fifty horses presented to the equine department of the university clinic, displaying no skin or mucous membrane lesions or severe signs of other diseases, were sampled. Methods: Cytobrush samples ...
Valente JDM, Mongruel ACB, Machado CAL, Chiyo L, Leandro AS, Britto AS, Martins TF, Barros-Filho IR, Biondo AW, Perotta JH, Campos ANS, Vidotto O....Tick-borne diseases (TBD) constitute an important group of illness affecting animals and humans worldwide. In Brazil, carthorses are frequently exposed to ticks and tick-borne pathogens, leading to impairment of horse performance and imposing restrictions by the international veterinary authorities for the importation of horses. Accordingly, this study has aimed to i) determine the prevalence of the TBD agents Theileria equi, Babesia caballi, Ehrlichia spp., and hemotropic mycoplasmas in carthorses, ii) identify the tick species parasitizing the animals, and iii) determine factors associated w...
Alpoim-Moreira J, Fernandes C, Rebordão MR, Amaral A, Pinto-Bravo P, Bliebernicht M, Skarzynski DJ, Ferreira-Dias G.Inflammation and fibroproliferative diseases may be modulated by epigenetic changes. Therefore, we suggest that epigenetic mechanisms could be involved in equine endometrosis pathogenesis. DNA methylation is one of the methods to evaluate epigenetics, through the transcription of methyltransferases (DNMT1, DNMT3A, DNMT3B). The correlation between DNMTs and collagen (COL) transcripts was assessed for the different Kenney and Doig's (Current Therapy in Theriogenology. Philadelphia: WB Saunders; 1986) endometrium categories. Endometrial biopsies were randomly collected from cyclic mares. Histolog...
Musilova P, Kubickova S, Zrnova E, Horin P, Vahala J, Rubes J.Using laser microdissection we prepared a set of horse chromosome arm-specific probes. Most of the probes were generated from horse chromosomes, some of them were derived from Equus zebra hartmannae. The set of probes were hybridized onto E. grevyi chromosomes in order to establish a genome-wide chromosomal correspondence between this zebra and horse. The use of arm-specific probes provided us with more information on the mutual arrangement of the genomes than we could obtain by means of whole-chromosome paints generated by flow sorting, even if we used reciprocal painting with probe sets from...
Riihimäki M, Aspán A, Ljung H, Pringle J.The aim of the study was to use culture, qPCR and seM sequencing to map Streptococcus equi subspec. equi (S.equi) isolates in long term carrier animals. A strangles outbreak affecting 41 Icelandic horses was followed to determine strangles free status using nasal and/or guttural pouch lavages collected serially on eleven separate occasions over 13 months. Ten persistent carriers, of which eight had repeated culture positive samples for S. equi, were selected for the study. Of 115 samples collected, 61 were S. equi positive on qPCR; from which 32 were also culture positive. Amplification of par...
Finno CJ, Stevens C, Young A, Affolter V, Joshi NA, Ramsay S, Bannasch DL.Horses belong to the order Perissodactyla and bear the majority of their weight on their third toe; therefore, tremendous force is applied to each hoof. An inherited disease characterized by a phenotype restricted to the dorsal hoof wall was identified in the Connemara pony. Hoof wall separation disease (HWSD) manifests clinically as separation of the dorsal hoof wall along the weight-bearing surface of the hoof during the first year of life. Parents of affected ponies appeared clinically normal, suggesting an autosomal recessive mode of inheritance. A case-control allelic genome wide associat...
Yao H, Osterrieder N, O'Callaghan DJ.The EICP0 gene (gene 63) of equine herpesvirus 1 (EHV-1) encodes an early regulatory protein that is a promiscuous trans-activator of all classes of viral genes. Bacterial artificial chromosome (BAC) technology and RecE/T cloning were employed to delete the EICP0 gene from EHV-1 strain KyA. Polymerase chain reaction, Southern blot analysis, and DNA sequencing confirmed the deletion of the EICP0 gene and its replacement with a kanamycin resistance gene in mutant KyA. Transfection of rabbit kidney cells with the EICP0 mutant genome produced infectious virus, indicating that the EICP0 gene is not...
Pusterla N, Mapes S, Johnson C, Slovis N, Page A, Gebhart C.The purpose of the current study was to compare the molecular detection rate of Lawsonia intracellularis between feces and rectal swabs collected from 42 foals with suspected equine proliferative enteropathy (EPE). Fecal samples and rectal swabs were processed for DNA purification by using an automated extraction system. The purified DNA was then analyzed by real-time polymerase chain reaction (PCR) for the presence of the aspartate ammonia lyase (aspA) gene of L. intracellularis. Absolute quantitation was calculated by using a standard curve for L. intracellularis and expressed as copy number...
Csizmár N, Mihók S, Jávor A, Kusza S.The Hungarian draft is a horse breed with a recent mixed ancestry created in the 1920s by crossing local mares with draught horses imported from France and Belgium. The interest in its conservation and characterization has increased over the last few years. The aim of this work is to contribute to the characterization of the endangered Hungarian heavy draft horse populations in order to obtain useful information to implement conservation strategies for these genetic stocks. Methods: To genetically characterize the breed and to set up the basis for a conservation program, in the present study a...
Knight CG, Munday JS, Rosa BV, Kiupel M.A 9-year-old gelding presented with approximately 100 papillomas that covered about 75% of the distal penis. Biopsy was performed, and histology showed evidence of viral cytopathic change and koilocytosis. Polymerase chain reaction using DNA extracted from biopsied tissue amplified equine papillomavirus type 2 (EcPV-2) DNA sequences. Sixteen months later, the horse was re-examined and the appearance of the papillomas was unchanged. Equine papillomavirus type 2 DNA sequences were again amplified from both biopsied tissue and swabs of the penis. Papillomavirus was localized to the lesions by imm...
Corado CR, McKemie DS, Young A, Knych HK.Metabolism is an essential factor in the clearance of many drugs and as such plays a major role in the establishment of dosage regimens and withdrawal times. CYP2D6, the human orthologue to equine CYP2D50, is a drug-metabolizing enzyme that is highly polymorphic in humans leading to widely differing levels of metabolic activity. As CYP2D6 is highly polymorphic, in this study it was hypothesized that the gene coding for the equine orthologue, CYP2D50, may also be prone to polymorphism. Blood samples were collected from 150 horses, the CYP2D50 gene was cloned and sequenced; and full-length seque...
Velineni S, Timoney JF.Streptococcus zooepidemicus of Lancefield group C is a highly variable tonsillar and mucosal commensal that usually is associated with opportunistic infections of the respiratory tract of vertebrate hosts. More-virulent clones have caused epizootics of severe respiratory disease in dogs and horses. The virulence factors of these strains are poorly understood. The antiphagocytic protein SeM is a major virulence factor and protective antigen of Streptococcus equi, a clonal biovar of an ancestral S. zooepidemicus strain. Although the genome of S. zooepidemicus strain H70, an equine isolate, conta...
Cai C, Zhao M, Yao F, Zhu R, Cai H, Shao S, Li XZ, Zhou T.Deoxynivalenol, a mycotoxin that may present in almost all cereal products, can cause huge economic losses in the agriculture industry and seriously endanger food safety and human health. Microbial detoxifications using microbial consortia may provide a safe and effective strategy for DON mitigation. In order to study the interactions involving DON degradation and change in microbial flora, four samples from different natural niches, including a chicken stable (expJ), a sheep stable (expY), a wheat field (expT) and a horse stable (expM) were collected and reacted with purified DON. After being...
Keyser-Tracqui C, Blandin-Frappin P, Francfort HP, Ricaut FX, Lepetz S, Crubézy E, Samashev Z, Ludes B.Sequence polymorphism of the mitochondrial DNA D-loop was used to determine the genetic diversity of horses recovered from a Scythian princely tomb dating from the beginning of the 3rd century BC. Eight haplotypes were found among the 13 ancient horse samples tested. Phylogenetical analysis showed that these ancient horse's sequences, along with two Yakut ones, were distributed throughout the tree defined by modern horses' sequences and are closely related to them. No clear geographical affiliation of the specimens studied was thus determined. Our work, among others, supports the very ancient ...
Löhr CV, Juan-Sallés C, Rosas-Rosas A, Parás García A, Garner MM, Teifke JP.Sarcoids were diagnosed in two captive zebras from different facilities. Zebra 1 (Equus burchellii boehmi) was a 4.5-yr-old, captive-born male that presented with a 9- by 7-cm inguinal mass. Seven months after surgical excision of the inguinal mass, the zebra presented with a similar lesion in the right upper eyelid that has relapsed repeatedly and has not responded to treatment including local cisplatin injections and cryosurgery. Zebra 2 (of undetermined taxon) was housed at a private wild animal farm. The zebra presented with a single, raised, 2.5- by 2.0- by 2.0-cm, ulcerated mass on the n...
Ongchai S, Somnoo O, Kongdang P, Peansukmanee S, Tangyuenyong S.We investigated the effect of transforming growth factor beta 1 (TGF-β1) on equine hyaluronan synthase 2 () gene expression and hyaluronan (HA) synthesis in culture models of articular chondrocytes. Equine chondrocytes were treated with TGF-β1 at different concentrations and times in monolayer cultures. In three-dimensional cultures, chondrocyte-seeded gelatin scaffolds were cultured in chondrogenic media containing 10 ng/mL of TGF-β1. The amounts of HA in conditioned media and in scaffolds were determined by enzyme-linked immunosorbent assays. mRNA expression was analyzed by semi-quantita...
Toribio RE, Kohn CW, Leone GW, Capen CC, Rosol TJ.In this study, we describe the cloning and tissue expression of equine calcitonin (CT), calcitonin-gene related peptide (CGRP)-I, and CGRP-II cDNA. We also describe a novel divergent form of CGRP (CGRP-I). Equine CT has greatest homology (>85%) to human, rat and mouse subgroups of calcitonins. Equine CGRP-I has low homology (80% homology to chicken, human, rat, ovine, swine, and bovine CGRPs. The homology between equine CGRP-I and CGRP-II is low (56%). The high homology of equine CGRP-II and the low homology of equine CGRP-I to CGRP in other species were unexpected findings. Northern blot a...
Nixon C, Chambers G, Ellsmore V, Campo MS, Burr P, Argyle DJ, Reid SW, Nasir L.Equine sarcoids are benign fibroblastic skin tumours affecting equids worldwide. Whilst the pathogenesis is not entirely understood, infection with Bovine Papillomavirus (BPV) types 1 and 2 has been implicated as a major factor in the disease process, however the mechanism by which BPV infection contributes to sarcoid pathology is not clear. In this study, we show that the majority of sarcoids express the BPV-1 major transforming gene E6. Further, we demonstrate that sarcoid lesions are not associated with high levels of cellular proliferation as assessed by Ki67 expression or with expression ...
Guo X, Izume S, Okada A, Ohya K, Kimura T, Fukushi H.A strain of equine herpesvirus type 1 (EHV-1) was isolated from zebra. This strain, called "zebra-borne EHV-1", was also isolated from an onager and a gazelle in zoological gardens in U.S.A. The full genome sequences of the 3 strains were determined. They shared 99% identities with each other, while they shared 98% and 95% identities with the horse derived EHV-1 and equine herpesvirus type 9, respectively. Sequence data indicated that the EHV-1 isolated from a polar bear in Germany is one of the zebra-borne EHV-1 and not a recombinant virus. These results indicated that zebra-borne EHV-1 is a ...
Love CC, Kenney RM.A variety of testicular insults can induce changes in the structure of spermatozoal chromatin, resulting in spermatozoal DNA that is more susceptible to acid-induced denaturation. The degree of change in the DNA can be measured using the sperm chromatin structure assay (SCSA). The SCSA measures the relative amounts of single- and double-stranded DNA after staining with the metachromatic dye, acridine orange. Here we used a stallion model (n = 4) to study the effects of scrotal heat stress on spermatozoal DNA. This model was created by insulating stallion testes for 48 h and collecting sperm da...
Thomson P, Pareja J, Núñez A, Santibáñez R, Castro R.Culture-independent techniques have made it possible to expand the knowledge about the composition of bacterial communities present in the healthy uterus and their role in health and disease, mainly in humans. However, in animals like mares, there is a dearth of information regarding this area. To narrow this knowledge gap, the objective of this study was to identify and characterize the composition and function of the uterine microbiome of a group of Chilean purebred mares (CPM), an equine breed with the oldest genealogical record in South America and an economical important reproductive indu...
Tydén E, Dahlberg J, Karlberg O, Höglund J.The development of anthelmintic resistance (AR) to macrocyclic lactones in the equine roundworm Parascaris equorum has resulted in benzimidazoles now being the most widely used substance to control Parascaris infections. However, over-reliance on one drug class is a risk factor for the development of AR. Consequently, benzimidazole resistance is widespread in several veterinary parasites, where it is associated with single nucleotide polymorphisms (SNPs) in drug targets encoded by the β-tubulin genes. The importance of these SNPs varies between different parasitic nematodes, but it has been h...
Battsetseg B, Lucero S, Xuan X, Claveria F, Byambaa B, Battur B, Boldbaatar D, Batsukh Z, Khaliunaa T, Battsetseg G, Igarashi I, Nagasawa H....Babesia equi (EMA-1) and Babesia caballi (BC48) gene fragments were amplified by polymerase chain reaction (PCR), in blood samples, and partially fed-females and egg and larval progenies of Dermacentor nuttalli, collected from horses in Altanbulag, Tuv Province, Mongolia. While Babesia parasite DNA was detected in some horse blood samples during the first PCR, all positive cases in partially fed-female ticks, eggs and larvae were confirmed by nested PCR. Present study reinforces earlier similar findings in unfed D. nuttalli ticks collected from an open space vegetation in Bayanonjuul, Tuv Prov...
Potocki L, Lewinska A, Klukowska-Rötzler J, Bugno-Poniewierska M, Koch C, Mählmann K, Janda J, Wnuk M.It is widely accepted that equine sarcoid disease, the most common skin associated neoplasm in equids, is induced by bovine papillomavirus (BPV-1). Although BPV-1 DNA has been found in almost all examined sarcoids so far, its detailed impact on the horse's host cell metabolism is largely unknown. We used equine fibroblast cell lines originating from sarcoid biopsies to study BPV-1-associated changes on DNA methylation status and oxidative stress parameters. Sarcoid-derived fibroblasts manifested increased proliferation in vitro, transcriptional rDNA activity (NORs expression) and DNA hypometh...
