Genetics in horses encompasses the study of hereditary traits and the genetic makeup that influences various characteristics and health conditions in equine populations. This field involves the analysis of genes and their functions, inheritance patterns, and the impact of genetic variations on traits such as coat color, performance ability, and susceptibility to diseases. Research in equine genetics employs techniques such as genome mapping, sequencing, and genetic testing to identify specific genes and mutations associated with these traits. This page gathers peer-reviewed research studies and scholarly articles that explore the genetic basis of equine traits, the methodologies used in genetic research, and the implications for breeding, health management, and conservation of horse breeds.
Forrester NL, Wertheim JO, Dugan VG, Auguste AJ, Lin D, Adams AP, Chen R, Gorchakov R, Leal G, Estrada-Franco JG, Pandya J, Halpin RA, Hari K, Jain R....Venezuelan equine encephalitis (VEE) complex alphaviruses are important re-emerging arboviruses that cause life-threatening disease in equids during epizootics as well as spillover human infections. We conducted a comprehensive analysis of VEE complex alphaviruses by sequencing the genomes of 94 strains and performing phylogenetic analyses of 130 isolates using complete open reading frames for the nonstructural and structural polyproteins. Our analyses confirmed purifying selection as a major mechanism influencing the evolution of these viruses as well as a confounding factor in molecular cloc...
Nemoto M, Bannai H, Ochi A, Niwa H, Murakami S, Tsujimura K, Yamanaka T, Kokado H, Kondo T.Getah virus is mosquito-borne and causes disease in horses and pigs. We sequenced and analyzed the complete genomes of three strains isolated from horses in Ibaraki Prefecture, eastern Japan, in 2016. They were almost identical to the genomes of strains recently isolated from horses, pigs, and mosquitoes in Japan.
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...
Steward KF, Robinson C, Maskell DJ, Nenci C, Waller AS.The Gram-positive bacterium subspecies () is the causative agent of strangles, among the most frequently diagnosed infectious diseases of horses worldwide. Genome analysis of strain 4047 (4047) identified a putative operon, Fim1, with similarity to the pilus loci of other Gram-positive bacteria. The Fim1 locus was present in all strains of and its close relative subspecies () that have been studied to date. In this study we provide evidence that the putative structural pilus proteins, SEQ_0936 and CNE, are produced on the cell surface during growth and infection. Although the proteins ...
Fu Z, Shi J.BACKGROUND The differences between the peripheral and central branches of the dorsal root ganglion (DRG) have not been fully elucidated. This study aimed to explore the expression of tubulin post-translational modifications (acetylation and deacetylation) between damaged peripheral and central branches of DRG neurons. MATERIAL AND METHODS Fifty Sprague-Dawley rats were randomly assigned to five groups with 10 rats in each group. These five groups consisted of spinal nerve ligation (SNL) at 24 hour and 48 hour, and cauda equina compression (CEC) at 24 hour and 48 hour, and a sham group. SNL inj...
Khan A, Mushtaq MH, Ahmad MUD, Nazir J, Farooqi SH, Khan A.A widespread epidemic of equine influenza (EI) occurred in nonvaccinated equine population across multiple districts in Khyber Pakhtunkhwa Province of Pakistan during 2015-2016. An epidemiological surveillance study was conducted from Oct 2015 to April 2016 to investigate the outbreak. EI virus strains were isolated in embryonated eggs from suspected equines swab samples and were subjected to genome sequencing using M13 tagged segment specific primers. Phylogenetic analyses of the nucleotide sequences were concluded using Geneious. Haemagglutinin (HA), Neuraminidase (NA), Matrix (M) and nucleo...
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, ...
Valenzuela OA, Couturier-Tarrade A, Choi YH, Aubrière MC, Ritthaler J, Chavatte-Palmer P, Hinrichs K.Assisted reproductive technologies (ARTs) such as intracytoplasmic sperm injection (ICSI), in vitro embryo culture and embryo transfer (ET) may be associated with alterations in fetal and placental development. In horses, ET has been used for decades. More recently, in vitro embryo production by ICSI and in vitro culture, followed by embryo transfer (ICSI-C) has become an accepted method for clinical foal production. However, no information is available on the effects of ICSI-C or even of standard ET itself on placental and neonatal parameters in horses. We therefore evaluated placental and ne...
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...
Garcia-Muñoz A, Valldecabres-Torres X, Newcombe JR, Cuervo-Arango J, Garcia-Rosello E.The objective of this study was to determine the effect of exogenous progesterone administration at ovulation and during the early development of the CL, on its future sensitivity to a single administration of PGF2a in mares and cows. Horse Retrospective reproductive data from an equine clinic in the UK during three breeding seasons were used. Mares were divided into: control group, cycles with single ovulations; double ovulation group cycles with asynchronous double ovulations; and PRID group: cycles with single ovulations and treatment with intravaginal progesterone device (CIDR) immediately...
Mach N, Foury A, Kittelmann S, Reigner F, Moroldo M, Ballester M, Esquerré D, Rivière J, Sallé G, Gérard P, Moisan MP, Lansade L.Weaning has been described as one of the most stressful events in the life of horses. Given the importance of the interaction between the gut-brain axis and gut microbiota under stress, we evaluated (i) the effect of two different weaning methods on the composition of gut microbiota across time and (ii) how the shifts of gut microbiota composition after weaning affect the host. A total of 34 foals were randomly subjected to a progressive (P) or an abrupt (A) weaning method. In the P method, mares were separated from foals at progressively increasing intervals every day, starting from five min ...
Schnider D, Rieder S, Leeb T, Gerber V, Neuditschko M.Recurrent airway obstruction (RAO), also known as heaves, is an asthma-like respiratory disease. Its development is strongly influenced by environmental risk factors such as sensitization and exposure to moldy hay, straw bedding and stabling indoors. A hereditary component has been documented in previous studies; however, so far no causative genetic variant that influences the risk of developing RAO has been identified. In this study, we revised an existing dataset and selected 384 horses for genotyping on the Affymetrix high-density equine SNP array. We performed an allelic case-control genom...
Kheder MH, Sillence MN, Bryant LM, de Laat MA.Metabolic disease is a significant problem that causes a range of species-specific comorbidities. Recently, a better understanding of glucose-dependent insulinotropic polypeptide (GIP) biology has led to the suggestion that inhibiting its action may attenuate obesity in several species. In horses, antagonism of GIP may also reduce hyperinsulinemia, which leads to insulin-associated laminitis, a painful comorbidity unique to this species. However, little is known about GIP in horses. The aims of this study were to examine the tissue distribution of equine GIP receptors (eGIPR), to determine whe...
Zhang Y, Chahan B, Liu S, Song R, Li Y, Huercha , Guo Q, Wu H, Zhu Y.In order to found the epidemiological situation of T. equi in the horse herds in Ili Prefecture of Xinjiang Province, 723 blood samples collected from 4 counties and districts were test for T. equi through microscopic detection and Polymerase chain Reaction (PCR). In the result, we found that the 295 of 723 blood samples (40.8%) were positive for T. equi infection. The results showed that the choosed counties have a varying degrees infection. To our knowledge, this is the first time that we detected T. equi infection using the molecular techniques from Ili in Xinjiang Uygur Autonomous region.
Onogi A, Shirai K, Amano T.Because native breeds can serve as genetic resources for adapting to environment changes, their conservation is important for future agroecosystems. Using pedigree analysis, we investigated genetic diversity and inbreeding in Japanese Hokkaido native horses, which have adapted to a cold climate and roughage diet. Genetic diversity was measured as the number of founders and the effective number of founders, ancestors and genomes. All metrics imply a decrease in genetic diversity. A comparison of these metrics suggested that pedigree bottlenecks contributed more than did random gene losses to th...
Iacono E, Pascucci L, Rossi B, Bazzucchi C, Lanci A, Ceccoli M, Merlo B.Both in human and equine species, mesenchymal stem cells (MSCs) from amniotic membrane (AM) and Wharton's jelly (WJ), may be particularly useful for immediate use or in later stages of life, after cryopreservation in cell bank. The aim of this study was to compare equine AM- and WJ-MSCs features that may be relevant for their clinical employment. MSCs were more easily isolated from WJ, even if MSCs derived from AM exhibited more rapid proliferation ( < 0.05). Osteogenic and chondrogenic differentiation were more prominent in MSCs derived from WJ. This is also suggested by the lower adh...
Mahdavi FS, Salehi A, Seyedjafari E, Mohammadi-Sangcheshmeh A, Ardeshirylajimi A.Horses with big bone fractures have low chance to live mainly due to the lake of a proper treatment strategy. We believe that further attempts in equine bone tissue engineering will probably be required to meet all the needs for the lesion therapies. Therefore in this study we aimed to investigate the osteogenic differentiation capacity of equine adipose-derived stem cells (e-ASCs) on nano-bioactive glass (nBGs) coated poly(l-lactic acid) (PLLA) nanofibers scaffold (nBG-PLLA). Using electrospinning technique, PLLA scaffold was prepared successfully and coated with nBGs. Fabricated nanofibers w...
Zutz C, Wagener K, Yankova D, Eder S, Möstl E, Drillich M, Rychli K, Wagner M, Strauss J.Estrogenic active compounds are present in a variety of sources and may alter biological functions in vertebrates. Therefore, it is crucial to develop innovative analytical systems that allow us to screen a broad spectrum of matrices and deliver fast and reliable results. We present the adaptation and validation of a fungal biosensor for the detection of estrogen activity in cow derived samples and tested the clinical applicability for pregnancy diagnosis in 140 mares and 120 cows. As biosensor we used a previously engineered genetically modified strain of the filamentous fungus Aspergillus ni...
Rink BE, Amilon KR, Esteves CL, French HM, Watson E, Aurich C, Donadeu FX.Equine mesenchymal stromal/stem cells (MSCs) are most commonly harvested from bone marrow (BM) or adipose tissue, requiring the use of surgical procedures. By contrast, the uterus can be accessed nonsurgically, and may provide a more readily available cell source. While human endometrium is known to harbor mesenchymal precursor cells, MSCs have not been identified in equine endometrium. This study reports the isolation, culture, and characterization of MSCs from equine endometrium. The presence of MSC and pericyte markers in endometrial sections was determined using immunohistochemistry. Strom...
Baj A, Beltramini GA, Romano M, Lauritano D, Gaudio RM, Palmieri A, Cura F, Giannì AB.BIOPAD® is an ivory-white soft sponge, made exclusively of lyophilized type I native heterologous collagen extracted from horse flexor tendon, gelatine free, that keeps its native structure specific to the body’s skin tissue. BIOPAD® is an active dressing, playing an active role in all stages of wound healing process, stimulating granulation tissue growth and enhancing regeneration tissues. It ensures balance between absorption and humidity at wound surface, gaseous exchange of soft tissues during healing process, barrier to prevent bacterial infections and it is completely non-adherent. T...
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...
Lecchi C, Dalla Costa E, Lebelt D, Ferrante V, Canali E, Ceciliani F, Stucke D, Minero M.Circulating microRNAs (miRNAs) are emerging as promising biomarkers for several disorders and related pain. In equine practice, acute laminitis is a common disease characterised by intense pain that severely compromises horse welfare. Recently, the Horse Grimace Scale (HGS), a facial expression-based pain coding system, was shown to be a valid welfare indicator to identify pain linked to acute laminitis. The present study aimed to: determine whether miRNAs can be used as biomarkers for acute pain in horses (Equus caballus) affected by laminitis; integrate miRNAs to their target genes and to ca...
Janes JG, Kennedy LA, Garrett KS, Engiles JB.Equine catastrophic skeletal breakdown injury is a serious issue within the racing industry, given the impact on equine and human health. The metacarpo- and metatarso-phalangeal (fetlock) joints are common sites of catastrophic injury. However, lesions involving articular cartilage, subchondral bone, and synovium are commonly identified within the fetlock of the contralateral limb; hence, it is imperative that lesions in both limbs are evaluated and characterized during postmortem examination. Bone and articular cartilage changes typically occur in specific locations, related to cyclic fetlock...
Plapp BV, Savarimuthu BR, Ferraro DJ, Rubach JK, Brown EN, Ramaswamy S.During catalysis by liver alcohol dehydrogenase (ADH), a water bound to the catalytic zinc is replaced by the oxygen of the substrates. The mechanism might involve a pentacoordinated zinc or a double-displacement reaction with participation by a nearby glutamate residue, as suggested by studies of human ADH3, yeast ADH1, and some other tetrameric ADHs. Zinc coordination and participation of water in the enzyme mechanism were investigated by X-ray crystallography. The apoenzyme and its complex with adenosine 5'-diphosphoribose have an open protein conformation with the catalytic zinc in one pos...
Murase H, Miyazawa M, Harada T, Ozawa M, Sato F, Hada T.The degree of fetal growth restriction has been unclear in equine reproduction. In this study, 2,195 fetuses from 2,137 abortions during 11 seasons were examined to determine the causes of abortion, and fetal size dimensions (crown rump length and body weight) were measured. In total, 900 cases (42.1%) of abortion were identified as caused by viral infection (215, 10.1%), bacterial infection (156, 7.3%), fungal infection (25, 1.2%), circulation failure (406, 19.0%), multiple causes (66, 3.1%), deformity (13, 0.6%), placental abnormality (12, 0.6%), and other causes (7, 0.3%). All viral infecti...
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...
Sakamoto T, Fawcett JA, Innan H.Horses have substantial variation in coat color, and the genetic loci responsible for the coat color variations have been well investigated. It has been believed that some color variations should follow a single-locus Mendelian law. Examples include the Gray locus that causes the gray phenotype and the Extension locus that specifies the chestnut phenotype. We reevaluated the roles of the Gray and Extension loci by using a large number of mating records of Thoroughbred racing horses. We showed that the data indeed fits the Mendelian law extremely well for the two loci. Furthermore, we demonstra...
Hagen A, Holland H, Brandt VP, Doll CU, Häußler TC, Melzer M, Moellerberndt J, Lehmann H, Burk J.Platelet lysate (PL) is an attractive platelet-based therapeutic tool and has shown promise as xeno-free replacement for fetal bovine serum (FBS) in human and equine mesenchymal stromal cell (MSC) culture. Here, we established a scalable buffy-coat-based protocol for canine PL (cPL) production (n = 12). The cPL was tested in canine adipose MSC (n = 5) culture compared to FBS. For further comparison, equine adipose MSC (n = 5) were cultured with analogous equine PL (ePL) or FBS. During canine blood processing, platelet and transforming growth factor-β1 concentrations increased ( < 0.05 and < ...
Grilz-Seger G, Reiter S, Neuditschko M, Wallner B, Rieder S, Leeb T, Jagannathan V, Mesarič M, Cotman M, Pausch H, Lindgren G, Velie B, Horna M....The roan coat color in horses is characterized by dispersed white hair and dark points. This phenotype segregates in a broad range of horse breeds, while the underlying genetic background is still unknown. Previous studies mapped the roan locus to the KIT gene on equine chromosome 3 (ECA3). However, this association could not be validated across different horse breeds. Performing a genome-wide association analysis (GWAS) in Noriker horses, we identified a single nucleotide polymorphism (SNP) (ECA3:g.79,543.439 A > G) in the intron 17 of the KIT gene. The G -allele of the top associated SNP...
Almeida J, Conley AJ, Mathewson L, Ball BA.Sertoli cells are essential in development of a functional testis. During puberty, Sertoli cell maturation can be characterized by a number of markers, including anti-Müllerian hormone (AMH) and its receptor (AMHR2), androgen receptor (AR), cyclin-dependent kinase inhibitor (CDKN1B), and connexin 43 (Cx43). In the present study, immunohistochemistry (IHC) and real-time quantitative polymerase chain reaction (RT-qPCR) were used to characterize changes in expression of AMH, AMHR2, AR, CDKN1B, and Cx43 in prepubertal, postpubertal, and adult equine testes. During puberty, AMH expression decrease...
Liu M, Liu T, Bordin A, Nerren J, Cohen N.Toll-like receptor 9 (TLR9) activation stimulates protective immune responses against intracellular pathogens by phagocytes, including neutrophils. This study examined TLR9-mediated neutrophil activation in neonatal foals. Unmethylated CpGs, ligands for TLR9, were used to stimulate equine neutrophils, either purified or in contact with other peripheral blood leukocytes. Rhodococcus equi was used as another stimulus in parallel. TLR9 mRNA was constitutively expressed at a similar level in purified equine neutrophils across different ages from birth to adulthood, and expression was not affected ...
Trailovic SM, Rajkovic M, Marjanovic DS, Neveu C, Charvet CL. sp. is the only ascarid parasitic nematode in equids and one of the most threatening infectious organisms in horses. Only a limited number of compounds are available for treatment of horse helminthiasis, and sp. worms have developed resistance to the three major anthelmintic families. In order to overcome the appearance of resistance, there is an urgent need for new therapeutic strategies. The active ingredients of herbal essential oils are potentially effective antiparasitic drugs. Carvacrol is one of the principal chemicals of essential oil from , , , , and herbs. However, the antiparasi...
Soboll G, Hussey SB, Whalley JM, Allen GP, Koen MT, Santucci N, Fraser DG, Macklin MD, Swain WF, Lunn DP.Equine herpesvirus-1 (EHV-1) is the cause of serious disease with high economic impact on the horse industry, as outbreaks of EHV-1 disease occur every year despite the frequent use of vaccines. Cytotoxic T-lymphocytes (CTLs) are important for protection from primary and reactivating latent EHV-1 infection. DNA vaccination is a powerful technique for stimulating CTLs, and the aim of this study was to assess antibody and cellular immune responses and protection resulting from DNA vaccination of ponies with combinations of EHV-1 genes. Fifteen ponies were divided into three groups of five ponies...
Huszar G, Patrizio P, Vigue L, Willets M, Wilker C, Adhoot D, Johnson L.Although in several species there is a relationship between epididymal sperm transport and fertility, in human in vitro fertilization (IVF), spermatozoa recovered from the caput epididymidis or even the rete testis are fertile. We studied two objective markers of sperm maturity in the sperm of men and stallions: creatine kinase (CK) concentrations, which are a measure of cytoplasmic retention in immature spermatozoa, and the ratio of CK-M and CK-B isoforms (% CK-M/[CK-M + CK-B]), which is proportional to the incidence of mature sperm. The CK markers and the fertilizing function are closely rel...
Rovere G, Ducro BJ, van Arendonk JA, Norberg E, Madsen P.Most Warmblood horse studbooks aim to improve the performance in dressage and show jumping. The Dutch Royal Warmblood Studbook (KWPN) includes the highest score achieved in competition by a horse to evaluate its genetic ability of performance. However, the records collected during competition are associated with some aspects that might affect the quality of the genetic evaluation based on these records. These aspects include the influence of rider, censoring and preselection of the data. The aim of this study was to quantify the impact of rider effect, censoring and preselection on the genetic...
Laseca N, Anaya G, Peña Z, Pirosanto Y, Molina A, Demyda Peyrás S.Fertility is one of the key factors in the economic and productive success of the equine industry. Despite this, studies on the genetic causes affecting reproductive performance are scarce, especially in mares, where the genetic architecture of the reproductive traits is extremely complex. Today, with the increasing availability of new genomic methodologies for this species, we are presented with an interesting opportunity to understand the genetic basis of equine reproductive disorders. These include, among others, novel techniques for detecting chromosomal abnormalities, whose association wi...
Thomas PG, Ball BA, Brinsko SP.Regulation of attachment of equine spermatozoa to homologous oviduct epithelium was investigated by co-culture of spermatozoa with oviductal epithelial cell explants. Stallion spermatozoa were incubated with explants derived from the isthmus and ampulla of follicular, postovulatory, and diestrous mares. Steroid treatments (estradiol, progesterone, or control) were applied across all explant groups. Estimates of motility and total numbers of attached spermatozoa were made 0.5, 24, and 48 h after initiation of co-culture. Equine spermatozoa attached by their rostral acrosomal region to both cili...
Reissmann M, Musa L, Zakizadeh S, Ludwig A.Considering the hidden mode of inheritance of some coat-color-associated alleles, we investigated the presence/absence of coat-color-associated alleles in 1093 domestic horses of 55 breeds and 20 specimens of Przewalski's horse. For coat-color genotyping, allele specific PCR, pyrosequencing and Li-Cor analyses were conducted on 12 coat-color-associated alleles of five genes. Our data provide deep insight into the distribution of coat-color-associated alleles within breeds. We found that the alleles for the basic colorations (bay, black, and chestnut) are widely distributed and occur in nearly ...
Liu MA.Gene-based vaccines are under development for a broad variety of applications, ranging from vaccines to immunotherapies for infectious diseases, cancer, autoimmune diseases and allergy. In addition, following the licensing of DNA vaccines for use in fish and horses, and DNA immunotherapy for the treatment of cancer in dogs, several veterinary uses of vaccines have been demonstrated for species ranging from fish and shrimp to cattle and horses. A variety of publications describing preclinical and clinical studies of the technologies used to increase the potency of gene-based vaccines, and resea...
Kakoi H, Kikuchi M, Tozaki T, Hirota KI, Nagata SI, Hobo S, Takasu M.The distribution of Y chromosomal haplotypes in Japanese native horse populations was investigated to obtain genetic information on these populations. Here, 159 male/gelded horses from eight local populations were investigated, and three Y haplotypes (JHT-1, JHT-2, and JHT-3) were identified by analyzing five Y-linked loci. Five populations had only JHT-1, whereas two populations had only JHT-2. One population had JHT-1 and JHT-3. Based on the geographical distribution of these haplotypes and previously reported haplotypes for other Asian horses, JHT-1 is considered to be a major haplotype in ...
Gambini A, Maserati M.Interest in equine somatic cell nuclear transfer technology has increased significantly since the first equid clones were produced in 2003. This is demonstrated by the multiple commercial equine cloning companies having produced numerous cloned equids to date; worldwide, more than 370 cloned horses have been produced in at least six different countries. Equine cloning can be performed using several different approaches, each with different rates of success. In this review we cover the history and applications of equine cloning and summarise the major scientific advances in the development of t...
Sandoval-Castellanos E, Wutke S, Gonzalez-Salazar C, Ludwig A.Wild horses unexpectedly survived terminal Pleistocene megafaunal extinctions until eventual European extirpation in the twentieth century. This survival is tied to either their occurrence in cryptic open habitats or their adaptation to forests. Our niche modelling inferred an increasing presence of horses in post-glacial forests, and our analysis of ancient DNA suggested significant selection for black phenotypes as indicating adaptation to forests.
Zhu H, Gifford RJ, Murcia PR.The evolution of mammalian genomes has been shaped by interactions with endogenous retroviruses (ERVs). In this study, we investigated the distribution and diversity of ERVs in the mammalian order , with a view to understanding their impact on the evolution of modern equids (family ). We characterize the major ERV lineages in the horse genome in terms of their genomic distribution, ancestral genome organization, and time of activity. Our results show that subsequent to their ancestral divergence from rhinoceroses and tapirs, equids acquired four novel ERV lineages. We show that two of these ER...
Jaworska J, Janowski T.Retained fetal membranes (RFM) is a prevalent postpartum disease in mares. During parturition, various proinflammatory cytokines are released in the placenta, which further facilitates uterine contractions, expulsion of the fetus and fetal membranes. We hypothesized that an altered inflammatory response in mares results in retained fetal membranes. Samples of the endometrium and the allantochorion were collected from 15 mares with RFM and from 29 control mares within 2 h of foal delivery. Next, the mRNA expression of IL-1β, IL-6 and TNFα proteins was analyzed by Real Time PCR and Western b...
Duru S.The aim of this study was to evaluate genetic variability in the Turkish Arab horse population using pedigree information. This study is the first detailed pedigree analysis of the breed in Turkey. Pedigree data were collected from the National Studbook. The pedigree data for 23 668 horses, born between 1904 and 2014, were used in the analysis. From this data set, a reference population (RP) of 14 838 animals symbolising the last generation was defined. Demographic parameters, the inbreeding level (F), the average relatedness (AR), the effective population size (N e), the effective number of f...
Patton JF, Balasuriya UB, Hedges JF, Schweidler TM, Hullinger PJ, MacLachlan NJ.An avirulent, novel variant of equine arteritis virus (EAV; CA95G) was isolated from the semen of a persistently infected Standardbred stallion. The CA95G virus caused subclinical infection and seroconversion in susceptible horses, and virus was isolated only once from blood and nasal secretions collected from 6 experimentally infected horses. Sequence analysis of genes encoding the known EAV structural proteins shows that this highly attenuated strain of EAV is genetically similar to virulent field strains of EAV and, in particular, to a strain of EAV that was isolated during an outbreak of e...
Bartolomé E, Menéndez-Buxadera A, Molina A, Valera M.To obtain a sport horse that excels in the highest levels of competition, breeders must take into account certain genetic and environmental factors that could influence the sport horse's performance, such as the rider-horse interaction (RHI). The main aim of this study was to describe this interaction in a genetic model by modelling it in relation to the horse's age. A total of 31,129 sport results from Spanish Sport Horses were used from a total of 1,101 animals evaluated, and these were grouped in three age levels and had been ridden by 606 different riders. Only riders who had ridden more t...
Liu LL, Fang C, Liu WJ.The utility of high-density single nucleotide polymorphism (SNP) data help to accurately identify genomic regions that have undergone positive selection. In this study, the Affymetrix Equine 670 K high-density SNP array was used to genotype Kazakh and Yili horse population. After quality control, 370,227 autosomal SNPs were used to detect selection signatures by using global fixation index (F) and cross-population extended haplotype homozygosity (XP-EHH). The database of Ensemble, Genecards, and NCBI were used to make gene annotation and functional analysis. The results showed that there wer...
The Journal of heredityNovember 5, 1997
Volume 88, Issue 5 355-357 doi: 10.1093/oxfordjournals.jhered.a023117
Short RV.Haldane's law states that in interspecific hybrids, it is the heterogametic sex that is likely to be absent, rare, or sterile. In mammals, there is increasing evidence to suggest that this may be due to the high mutation rate of male sex-determining genes on the Y chromosome. The mule, humanity's first successful attempt at genetic engineering, provides some support for this concept. Interspecific hybrids may also shed new light on the importance of the maternal transmission of mitochondrial DNA and the phenomenon of genomic imprinting.
Colleoni S, Luciano AM, Gandolfi F.Horse is a seasonal breeder and information on oocyte quality outside the breeding season is very limited. Ovaries obtained at the slaughterhouse are a convenient but often limited source of oocytes in this species. As the low quantity of ovaries leads to an intensive use of all available material, it would be useful to know whether ovaries collected during the non-breeding season are suitable for in vitro maturation (IVM). In an attempt to characterize the effect of season on oocyte quality, we investigated the permeability of the gap junctions (GJ) present between cumulus cells and oocytes b...
Na W, Kang B, Kim HI, Hong M, Park SJ, Jeoung HY, An DJ, Moon H, Kim JK, Song D.Equine influenza virus (EIV) causes a highly contagious respiratory disease in equids, with confirmed outbreaks in Europe, America, North Africa, and Asia. Although China, Mongolia, and Japan have reported equine influenza outbreaks, Korea has not. Since 2011, we have conducted a routine surveillance programme to detect EIV at domestic stud farms, and isolated H3N8 EIV from horses showing respiratory disease symptoms. Here, we characterized the genetic and biological properties of this novel Korean H3N8 EIV isolate. This H3N8 EIV isolate belongs to the Florida sublineage clade 1 of the America...
Fincham DA, Mason DK, Young JD.Horse erythrocytes are polymorphic with respect to L-alanine permeability. The present investigation compared the specificity, kinetics and cation-dependence of erythrocyte amino acid transport in two groups of thoroughbred horses, those with erythrocyte L-alanine permeabilities in the range 5-15 mumol/h per litre of cells (0.2 mM extracellular L-alanine, 37 degrees C) (transport-negative type) and those with L-alanine permeabilities in the range 450-700 mumol/h per litre of cells (transport-positive type). Transport-positive cells are shown to possess a novel high-affinity, stereospecific, Na...
Breathnach CC, Rudersdorf R, Lunn DP.Recombinant modified vaccinia Ankara (MVA) vectors expressing equine influenza virus genes were constructed and evaluated for use in equine vaccination. Two strains of recombinant MVA, expressing either hemagglutinin (HA) or nucleoprotein (NP) genes were constructed. Each influenza virus gene was cloned from A/equine/Kentucky/1/81 (Eq/Ky) into an MVA construction plasmid, and was introduced to the deletion III locus of the wild type MVA genome by homologous recombination. Recombinant viruses were plaque purified, and antigen expression was confirmed by immunostaining. Two ponies were primed by...
Perdomo-González DI, Molina A, Sánchez-Guerrero MJ, Bartolomé E, Varona L, Valera M.Fertility is a key factor in the economic success of horse farms. However, it has received little attention due to the difficulty of measuring fertility objectively. Since its studbook creation (1912), the Pura Raza Española (PRE) breed has been a closed population and become high in-bred resulting in inbreeding depression (poor phenotypic values). Nevertheless, heterogeneous effects of inbreeding depression have been detected among founders and nonfounders. The aims of this study were (1) to analyze the genetic parameters for reproductive traits in mares of the PRE horse breed and (2) to est...
Rejmanek D, Miller MA, Grigg ME, Crosbie PR, Conrad PA.Sarcocystis neurona is a significant cause of neurological disease in horses and other animals, including the threatened Southern sea otter (Enhydra lutris nereis). Opossums (Didelphis virginiana), the only known definitive hosts for S. neurona in North America, are an introduced species in California. S. neurona DNA isolated from sporocysts and/or infected tissues of 10 opossums, 6 horses, 1 cat, 23 Southern sea otters, and 1 harbor porpoise (Phocoena phocoena) with natural infections was analyzed based on 15 genetic markers, including the first internal transcribed spacer (ITS-1) region; the...
Hahn CN, Matiasek K, Dixon PM, Molony V, Rodenacker K, Mayhew IG.Recurrent laryngeal neuropathy (RLN) is a common and debilitating peripheral nerve disease of horses, but it remains unclear if this disease is a mono- or polyneuropathy. An understanding of the distribution of the neuropathological lesions in RLN affected horses is fundamental to studying the aetiology of this very significant disease of tall horses. Objective: To determine whether RLN should be classified as a mono- or polyneuropathy. Methods: Multiple long peripheral nerves and their innervated muscles were examined systematically in 3 clinically affected RLN horses Results: Severe lesions ...
He Z, Dai X, Lyu W, Beaumont M, Yu F.Novel technologies for recovering DNA information from archaeological and historical specimens have made available an ever-increasing amount of temporally spaced genetic samples from natural populations. These genetic time series permit the direct assessment of patterns of temporal changes in allele frequencies and hold the promise of improving power for the inference of selection. Increased time resolution can further facilitate testing hypotheses regarding the drivers of past selection events such as the incidence of plant and animal domestication. However, studying past selection processes ...
