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.
Bauerfeind R, Barth S, Weiss R, Baljer G.Strains of Salmonella isolated from animals in Germany (n = 878) were analysed for the presence of the spvD gene ("Salmonella plasmid virulence gene D") by DNA-DNA hybridization. The spvD gene was only detected in strains of serovars Typhimurium (93.3%), Enteritidis (97.1%), and Dublin (100%) as well as in two rough strains of Salmonella enterica. Salmonella isolates from mammals carried the gene more frequently (cattle 94.0%, horses 92.6%, pigs 73.7%) than those from birds (33.3%) or reptiles (4.5%). Due to its high prevalence in epidemiologically relevant salmonellae, the virulence factor sp...
MacLeay JM.In 1992, a multiparous 13-year-old Thoroughbred mare and her 48-hour-old colt were examined because of possible neonatal isoerythrolysis (NI). Supportive treatment was administered, and the foal recovered without requiring a transfusion. According to the owners, the mare had delivered foals without incident during 1987 and 1991. The mare was barren during 1993, but in 1994, delivered a filly that developed severe NI. The foal was given 3 transfusions and eventually recovered without complications. Blood typing analysis of the mare and its foals indicated that all 4 foals were positive for the ...
Heinzerling LM, Feige K, Rieder S, Akens MK, Dummer R, Stranzinger G, Moelling K.Preclinical studies investigating new therapeutic principles against melanoma are presently being carried out in mouse models; however, these are not optimal. Here we describe a novel animal model using gray horses. These animals spontaneously develop metastatic melanoma that resembles human disease and is thus highly relevant for preclinical studies testing new immunotherapy protocols. We found that injection of plasmid DNA coding for the human cytokine interleukin 12 into established metastases induced significant regression in all 12 treated lesions in a total of 7 horses. Complete disappea...
Kagawa S, Moore JE, Murayama O, Matsuda M.Eight strains of Taylorella equigenitalis were identified by a polymerase chain reaction using a primer pair specific to the 16S rDNA of T equigenitalis. These eight strains were chosen because they had previously been shown to represent eight distinct genotypes by pulsed-field gel electrophoresis analysis after separate digestion of the genomic DNA with ApaI or NotI. The eight strains could be classified into six or seven types by random amplified polymorphic DNA analysis using different kinds of primers. Amplified rDNA restriction analysis after separate digestion with five restriction enzym...
Choi YH, Love CC, Varner DD, Thompson JA, Hinrichs K.Two different culture media (TCM-199 and follicular fluid), two activation treatments (10 and 50 micromol calcium ionophore l(-1)) and three culture periods with cycloheximide were evaluated to find effective culture conditions for activation of cumulus-free equine oocytes. Oocytes were collected by scraping the follicle walls of ovaries obtained from an abattoir. Oocytes with expanded cumuli were matured at 38.2 degrees C in a humidified atmosphere of 5% CO(2) in air, in either TCM-199 with 10% fetal bovine serum (FBS) and 5 microU FSH ml(-1), or in 100% follicular fluid derived from a preovu...
Shubitowski DM, Venta PJ, Douglass CL, Zhou RX, Ewart SL.The continued discovery of polymorphisms in the equine genome will be important for future studies using genomic screens and fine mapping for the identification of disease genes. Segments of 50 equine genes were examined for variability in 10 different horse breeds using a pool-and-sequence method. We identified 11 single nucleotide polymorphisms (SNPs) in 9380 bp of sequenced exon, and 25 SNPs, six microsatellites, and one insertion/deletion in 16961 bp of sequenced intron. Of all genes studied 52% contained at least one polymorphism, and polymorphisms were found at an overall rate of 1/613 b...
Terry RR, Bailey E, Bernoco D, Cothran EG.The appaloosa coat colour pattern of the horse is similar to that caused by the rump-white (Rw) gene in the mouse. In the mouse Rw colour pattern is the result of an inversion involving the proto-oncogene c-kit (KIT). Therefore, we investigated KIT as a candidate gene that encodes the appaloosa coat colour gene (Lp) in horses. KIT plays a critical role in haematopoiesis, gametogenesis, and melanogenesis and encodes a transmembrane tyrosine kinase receptor that belongs to the PDGF/CSF-1/c-KIT receptor subfamily. Half-sib families segregating for Lp were uninformative for a reported polymorphism...
Bjørnstad G, Røed KH.Population demarcation of eight horse breeds was investigated using genotype information of 306 horses from 26 microsatellite loci. The breeds include the indigenous Norwegian breeds Fjord Horse, Nordland/Lyngen Horse, Døle Horse and Coldblooded Trotter together with Icelandic Horse, Shetland Pony, Standardbred and Thoroughbred. Both phylogenetic analysis and a maximum likelihood method were applied to examine the potential for breed allocation of individual animals. The phylogenetic analysis utilizing simple allele sharing statistics revealed clear demarcation among the breeds; 95% of the in...
Thway TM, Wolfe MW.Primates and equids are the only species known to express the placental glycoprotein hormone, chorionic gonadotropin (CG), a heterodimeric glycoprotein composed of an alpha subunit linked to a hormone-specific beta subunit. The regulatory mechanisms involved in the induction of equine glycoprotein alpha subunit gene expression have not been identified. Epidermal growth factor (EGF) receptor is known to transduce signals that alter a number of different cellular functions (cell proliferation, differentiation, hormone secretion, and gene regulation). In the present study, we investigated the reg...
Lindgren G, Swinburne JE, Breen M, Mariat D, Sandberg K, Guérin G, Ellegren H, Binns MM.A horse bacterial artificial chromosome (BAC) library was screened for 19 microsatellite markers from unassigned or non-oriented linkage groups. Clones containing 11 (AHT20, EB2E8, HMS45, LEX005, LEX014, LEX023, LEX044, TKY111, UCDEQ425, UCDEQ464 and VIASH21) of these were found, which were from eight different linkage groups. The BAC clones were used as probes in dual colour FISH to identify their precise chromosomal origin. The microsatellite markers are located on nine different horse chromosomes, four of which (ECA6, ECA25, ECA27 and ECA28) had no previously in situ assigned markers.
Acone F, Botti M, Gazza F, Sanna M, Cappai MG, Bo Minelli L.The sensitive and autonomic innervation of the prostate was studied in some mammals (rat, rabbit, horse, donkey and bull) using gold chloride impregnation. In all the species considered the gland was supplied with conspicuous innervation located in the thickness of the capsule and in trabeculae. The autonomic innervation was constituted by ganglion cells of different sizes (small, medium and large), isolated or in groups of large ganglia also, always located along the course of nerve bundles. The sensitive nervous component, placed more frequently in the most superficial layer of the capsule, ...
Lemazurier E, Sourdaine P, Nativelle C, Plainfossé B, Séralini G.Adult stallion secretes very high estrogen levels in its testicular vein and semen, and the responsible enzyme cytochrome P450 aromatase (P450 arom) is known to be present mainly in Leydig cells. We studied in further details the distribution of equine aromatase in various adult tissues including the brain (hypothalamic area), liver, kidney, small intestine, muscle, bulbourethral gland and testes. The aromatase mRNA was essentially detected by RT-PCR in testis (169+/-14 amol of aromatase mRNA per microg of total RNA) and was barely detectable in brain, or below 0.1 amol/microg RNA in other tis...
Crispin SM.The iris is derived from interaction between neural crest tissue and the adjacent neuroectoderm of the optic cup. Developmental anomalies of the equine iris are common, and include congenital miosis, iris cysts, various manifestations of iris hypoplasia, heterochromia, and persistent pupillary membrane remnants. They may be found alone or in combination with other ocular defects.
Sironi G, Riccaboni P, Mertel L, Cammarata G, Brooks DE.The expression of p53 protein was investigated in eight formalin-fixed, paraffin-embedded conjunctival squamous cell carcinomas of five horses and one cow, dog and cat each by an immunohistochemical procedure in order to evaluate protein overexpression. Anti-human p53 protein mouse monoclonal antibodies known to be cross-reactive with p53 protein of the animal species examined were used. Positive p53 nuclear immunostaining was detected in five equine, one bovine and one feline cases. Conversely, no p53 immunostaining was found in the only canine case examined. These results demonstrate a frequ...
Pellegrini M, Corda M, Manca L, Olianas A, Sanna MT, Fais A, De Rosa MC, Bertonati C, Masala B, Giardina B.A study was made of the haemoglobin (Hb) system from the Sardinian dwarf horse (Equus caballus jara), one of the last surviving wild horse species in Europe. The oxygen binding properties of the whole haemolysate and of the four different horse Hbs, separated by ion-exchange chromatography, were studied with special regard to the effect of chloride, 2,3-diphosphoglycerate and lactate. Results indicate that no significant functional differences exist between the four Hb components of horse haemolysate. Moreover, the molecular basis of the intrinsically low oxygen affinity and of the weak intera...
Lieto LD, Cothran EG.A cDNA library was built using RNA extracted from the skin tissue of an adult horse. The library was primed with oligo (dT) and sequences were directionally inserted in order to produce an expression library. The library has 5.8X 10(5) plaque forming units with 99.6% recombinant phage. The average insert size is 1.3 Kbp. Three hundred and thirteen expressed sequence tags (ESTs) were generated from sequencing of the 5 prime end of randomly selected skin cDNA clones. The ESTs were sequenced on an ABI 377 using Big-Dye chemistry. A similarity search was performed on each EST using the NCBI non-re...
Suire S, Stewart F, Beauchamp J, Kennedy MW.The equine conceptus is surrounded by a fibrous capsule that persists until about day 20 of pregnancy, whereupon the capsule is lost, the conceptus attaches to the endometrium and placentation proceeds. Before attachment, the endometrium secretes in abundance a protein of the lipocalin family, uterocalin. The cessation of secretion coincides with the end of the period during which the conceptus is enclosed in its capsule, suggesting that uterocalin is essential for the support of the embryo before direct contact between maternal and foetal tissues is established. Using recombinant protein and ...
Url A, Bauder B, Thalhammer J, Nowotny N, Kolodziejek J, Herout N, Fürst S, Weissenböck H.Neuronal ceroid lipofuscinosis (NCL) is an inherited, neurodegenerative disorder with fatal outcome in humans. It has also been described in some animal species; this is the first report of NCL in equines. Three horses showed developmental retardation, slow movements and loss of appetite at the age of six months. Neurological symptoms, as well as visual failure in one case, were noticed at the age of 1 year. Due to slowly progressing deterioration, euthanasia was indicated 1.5 years after onset of conspicuous behavior. At necropsy, slight flattening of the gyri and discoloring of the brain was...
Bullimore SR, Corfield AP, Hicks SJ, Goodall C, Carrington SD.In horses, ulceration of the non-glandular region of the stomach is common and has been attributed to the lack of a protective mucus covering. This study aimed to determine whether the non-glandular region is covered by a mucus layer. A mixture of antibodies raised against human gastric mucin (MUC 5 AC) showed a tissue distribution in the glandular region of the equine stomach similar to that seen in humans. Dot blots of mucus from the glandular and non-glandular regions showed cross-reactivity with these antibodies. Various histological fixation and processing techniques were compared for the...
Gable TL, Woods GL.The objectives were to compare cumulus type with nucleus form in equine cumulus oocyte complexes (COCs), to define the percentage of germinal vesicle (GV)-stage oocytes within a population of mares, and to further define GV nucleus shapes of equine oocytes. Cumulus types were as follows: 1) compact (56/208, 26.9%), 2) slightly expanded (37/208, 17.8%), 3) moderately expanded (27/208, 13.0%), 4) greatly expanded (15/208, 7.2%), or 5) denuded (73/208, 35.1%). One hundred thirty of 208 COCs (62.5%) were GV-stage, 21/208 (10.1%) were condensed chromatin-stage, 8/208 (3.8%) were polar body-stage, 4...
Gable TL, Woods GL.The objective was to test the hypothesis that increasing equine oocyte culture time from 48 to 96 or 144 h increases nucleus maturation of equine oocytes. The hypothesis was not supported because condensed chromatin-stage oocytes decreased (P<0.01) from 33/126 (26.2%) at 48 h or 34/95 (35.8%) at 96 h to 11/117 (9.4%) at 144 h, and polar body-stage oocytes decreased (P<0.01) from 65/126 (51.6%) at 48 h to 25/95 (26.3%) at 96 h and (P<0.01) to 1/117 (0.9%) at 144 h. Negative (non-staining) oocytes increased (P<0.01) from 16/126 (12.7%) at 48 h or 15/95 (15.8%) at 96 h to 39/117 (33.3%) at 144 h....
Rieder S, Taourit S, Mariat D, Langlois B, Guérin G.Coat color genetics, when successfully adapted and applied to different mammalian species, provides a good demonstration of the powerful concept of comparative genetics. Using cross-species techniques, we have cloned, sequenced, and characterized equine melanocortin-1-receptor (MC1R) and agouti-signaling-protein (ASIP), and completed a partial sequence of tyrosinase-related protein 1 (TYRP1). The coding sequences and parts of the flanking regions of those genes were systematically analyzed in 40 horses and mutations typed in a total of 120 horses. Our panel represented 22 different horse breed...
Martens A, De Moor A, Ducatelle R.The purpose of this study was to examine if bovine papilloma virus (BPV) DNA can be detected in superficial swabs or scrapings from equine sarcoids. Samples were obtained from 92 sarcoids and 20 non-sarcoidal control lesions. The polymerase chain reaction technique was used with a first primer set to check whether DNA extraction was successful, and with a second primer set specific for BPV-DNA. DNA isolation was successful in 88% of the swabs and 93% of the scrapings. All control lesions were negative for BPV-DNA.
Larsen LE, Storgaard T, Holm E.The study describes for the first time the phylogenetic relationship between equine arteritis virus (EAV) isolated from asymptomatic virus-shedding stallions and fatal cases of equine viral arteritis (EVA) in an European country. EAV was isolated from three dead foals and an aborted foetus during three different outbreaks of EVA. From these fatalities, the complete open reading frame 5, encoding the EAV G(L) protein, was amplified by reverse transcription-polymerase chain reaction and subjected to nucleotide sequence analysis. Furthermore, DNA sequences were obtained from virus isolated from s...
Davies Morel MC, O'Sullivan JA.Ovarian activity was monitored in 2181 oestrous cycles from 1136 thoroughbred brood mares to accurately determine overall ovulation rate, the relative distribution of ovulations between left and right ovary, whether mare age had an effect on these parameters and whether ovulation pattern in one cycle affected the pattern within the next. Ultrasonic scanning was used in preference to rectal palpation and slaughterhouse material due to its greater accuracy. Mare's ages ranged from 3 to 22 years. The results obtained indicated a similar incidence of ovulation occurring on the right (49.5% of all ...
Pickles KJ, Mair JA, Lopez-Villalobos N, Shaw DJ, Scott I, Pomroy W.Cyathostomins are the principal pathogenic nematode of equidae worldwide. In other species mast cell (MC) proteinases, in particular chymases, appear to have protective roles. Knowledge of the equine intestinal immune response to cyathostomins is limited. Objective: To investigate MC numbers and proteinase expression in equine cyathostomin-infected large intestine. Objective: MC populations in the large intestine are positively associated with cyathostomin burden and predominantly express chymase. Methods: The caecal cyathostomin burden of naturally infected horses (n = 25) was determined by l...
Fay JE, Douglas RH.Individual antral follicles from 11 horse mares were studied at three stages of the oestrous cycle to determine the characteristics of the presumptive ovulatory follicle. Mares were ovariectomized (ovex) during the late luteal phase on Day 14 after ovulation (Group 1) and on the 1st (Group 2) or 4th (Group 3) day of oestrus. Every follicle greater than 5 mm in diameter was dissected from each ovary; follicles greater than or equal to 15 mm in diameter were analysed separately while others were pooled by size for subsequent analyses. The presumptive ovulatory follicle possessed the following ch...
Divers TJ, Schappel KA, Sweeney RW, Tennant BC.Persistent hyperbilirubinemia and icterus are described in a healthy 4-year-old Thoroughbred horse. Hyperbilirubinemia was not related to food intake and was not associated with evidence of increased hemolysis or with acquired hepatic disease. The hyperbilirubinemia was thought to be a result of inappropriate conjugation of bilirubin rather than any abnormality in bilirubin uptake or excretion. The bilirubinemia in this horse appears most similar to a human syndrome, caused by a familial deficiency of bilirubin-uridine diphosphate glucuronyl transferase.
Choi YH, Penedo MC, Daftari P, Velez IC, Hinrichs K.Preimplantation genetic diagnosis has great potential in the horse, but information on evaluation of equine embryo biopsy samples is limited. Blastocysts were biopsied using a Piezo drill and methods for whole-genome amplification (WGA) investigated. Results for 33 genetic loci were then compared between biopsy samples from in vitro-produced (IVP) and in vivo-recovered (VIV) blastocysts. Under the experimental conditions described, WGA using the Qiagen Repli-g Midi kit was more accurate than that using the Illustra Genomiphi V2 kit (98.2% vs 25.8%, respectively). Using WGA with the Qiagen kit,...
Próchniak T, Rozempolska-Rucińska I, Zięba G, Łukaszewicz M.The aim of the study was to select traits that may constitute a prospective criterion for breeding value prediction of young horses. The results of 1,232 starts of 894 four-, five-, six-, and seven-year-old horses, obtained during jumping championships for young horses which had not been evaluated in, alternative to championships, training centres were analyed. Nine traits were chosen of those recorded: ranking in the championship, elimination (y/n), conformation, rating of style on day one, two, and three, and penalty points on day one, two, and three of a championship. (Co)variance component...
Hijazin M, Ulbegi-Mohyla H, Alber J, Lämmler C, Hassan AA, Prenger-Berninghoff E, Weiss R, Zschöck M.An Arcanobacterium haemolyticum strain isolated from a postcastrational lesion of a horse was identified phenotypically and genotypically. The latter was performed by sequencing the 16S-23S rDNA intergenic spacer region (ISR), by amplification of the gene encoding A. haemolyticum phospholipase D, by amplification of A. haemolyticum specific parts of ISR-23S rDNA and by amplification of the newly described CAMP factor family protein encoding gene of A. haemolyticum. This indicates (as described previously for seven additional A. haemolyticum strains; Hassan et al. 2009) that A. haemolyticum see...
Latham CM, Fenger CK, White SH.Responses of equine skeletal muscle characteristics to growth and training have been shown to differ between breeds. These differential responses may arise in part because muscle fiber type and mitochondrial density differ between breeds, even in untrained racing-bred horses. However, it is not known when these breed-specific differences manifest. To test the hypothesis that weanling Standardbreds (SB) and Thoroughbreds (TB) would have higher mitochondrial measures than Quarter Horses (QH), gluteus medius samples were collected from SB (mean ± SD; 6.2 ± 1.0 mo; n = 10), TB (6.1 ± 0.5 mo; n ...
Rajabi-Toustani R, Watanabe H, Tsogtgerel M, Gao Y, Canbo L, Haneda S, Cheong SH, Nambo Y.The main difficulty of large equine embryo cryopreservation is the replacement of blastocoel fluid with cryoprotectant solution. The objective of this study was to improve the cryopreservation of large equine embryos with PMAP and/or LAP. Embryos were collected via the non-surgical transcervical procedure and divided into three groups based on their size (A ≤ 300 µm, 300 µm<B 300 µm). However, more research is required to find the best method for embryos ≥700 µm.
Winter RL, Seeto WJ, Tian Y, Caldwell FJ, Lipke EA, Wooldridge AA.Endothelial progenitor cells (EPCs) contribute to neovascularization and vascular repair in vivo and are attractive for clinical use in ischemic disease. Tracking of stem and progenitor cells is essential to determine engraftment after administration. Semiconductor quantum dots (QD) are promising for cell labeling due to their ease of uptake by many cell lines and their continued presence after many cell generations. The purpose of this study was to evaluate function and growth of equine EPCs after QD labeling. Additionally, this study evaluated the duration of QD label retention and mechanism...
Ayad A, Almarzook S, Besseboua O, Aissanou S, Piórkowska K, Musiał AD, Stefaniuk-Szmukier M, Ropka-Molik K.Genetic disorders in horses are mostly fatal or usually cause significant economic losses for breeders and owners. Here we studied a total of 177 Arabian, Barb and Arab-Barb horses from the Middle East and North Africa (MENA) using Sanger Sequencing and PCR-ACRS (polymerase chain reaction-artificially created restriction site) approaches to examine the genetic disorders in the studied horse breeds. We identified the genetic variations related to Cerebellar Abiotrophy (CA), Severe Combined Immunodeficiency (SCID) occurrence, and the studied population was free of the mutant allele determined La...
Chen Q, Tong Q, Ge H, Li W, Liu J, Wang Y, Guo Z, Quan F, Zhang Y.SP110 has previously shown to be a genetic determinant of host resistance to the intracellular pathogen infection in mouse and human. However, its relevant biological information in large non-primate animals still remains unknown. Here we report the novel discovery and characterization of three transcript variants of horse SP110. The transcript variant 1 (Tv1) of horse SP110 with the longest open reading frame has four domains (Sp100, SAND, PHD and Bromo domain). Tv2 and Tv3 share the same N-terminal sequence as Tv1, which contains Sp100 and SAND. We show that Tv2 is generated from alternative...
Padilha FGF, El-Jaick KB, de Castro L, Moreira ADS, Ferreira AMR.Polymorphisms in MSTN have previously been associated with equine performance. Therefore, the aim of this study was to identify variants in intron 1 in 16 Brazilian Sport Horses selected for competition in eventing and their possible effects of selection on performance. Among the nine variants identified, eight had already been reported in previous studies or genomic databases, although they showed differences in frequencies when compared with other horse breeds. Moreover, a new mutation was identified in two horses, both in heterozygous form. Considering the absence of molecular studies in t...
Martini F, Angelaccio S, Barra D, Doonan S, Bossa F.Cytosolic aspartate aminotransferase (L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1) from horse heart has five cysteine residues, two of which can be titrated with 5,5'-dithiobis(2-nitrobenzoid acid) in the native enzyme with no impairment of catalytic activity. The rate of modification is unaffected by the presence of substrates. Reaction with N-ethylmaleimide leads to loss of catalytic activity, the rate of inactivation being increased by the presence of substrates. Peptides containing 361 amino-acid residues (about 88% of the total number in the protein) have been isolated and ali...
Lejeune JP, Serteyn D, Gangl M, Schneider N, Deby-Dupont G, Deberg M, Henrotin Y.Several breeds of draft horses suffer from degenerative digital osteoarthropathy, resulting in a reduced active lifespan. A group of 30 Ardenner horses was followed, in standardized conditions, from 15 to 28 months of age to detect the early manifestations of the disease. The severity of the disease was assessed according to a personal grading system including clinical and radiographic items. Coll 2-1, a peptide of the helical region of type II collagen, and its nitrated form (Coll 2-1 NO(2)) were assayed in blood plasma collected at 452 +/- 18 days, 504 +/- 20 days, 558 +/- 18 days, 613 +/- 1...
Torres A, Silva JF, Bernardes N, Sales Luís J, Lopes da Costa L.Here is reported a disorder of sex development found in the Portuguese Lusitano horse breed. The complex genital phenotype included mammary glands, abdominal testes without epididymis, connected through oviducts to pelvic hypoplastic uterine horns and fused vulvar labia majora from which protruded ventrally a penis-like structure. This structure was presented in a reversed position, the urethral opening placed dorsally in the glans. However, it was functional both for micturition and erection. The horse exhibited female micturition posture and aggressive male-like behaviour, including flehmen,...
Ataseven VS, Oğuzoğlu TÇ, Başaran-Karapınar Z, Bilge-Dağalp S.Equine adenovirus type 1 (EAdV-1) is a cause of repiratory tract infection in equids. In present study for the first time in Turkey, the prevalence of EAdV-1 in nasal swab samples obtained from horses showing respiratory symptoms was investigated by polymerase chain reaction (PCR), and molecular characterization of the hexon gene detected in the Turkish (TR) strain was performed. Overall, the prevalence of EAdV-1 was found low (1.4%) as indicated by a positive PCR reaction from the nasal swab extracts tested. Phylogenetic analysis based on the partial sequences of the hexon gene of a TR-EAdV-1...
Tozaki T, Inoue S, Mashima S, Ohta M, Miura N, Tomita M.Microsatellites are useful tools for the construction of a linkage map and parentage testing of equines, but only a limited number of equine microsatellites have been elucidated. Thus, we constructed the equine genomic library enriched for DNA fragments containing (CAG)n repeats. The enriched method includes hybridization-capture of repeat regions using biotin-conjugated oligonucleotides, nucleotide substrate-biased polymerase reaction with the oligonucleotides and subsequent PCR amplification, because these procedures are useful for the cloning of less abundant trinucleotide microsatellites. ...
Meyerholz DK, Caston SS, Haynes JS.An Appaloosa filly was born with a ventral midline, approximately 8 x 12 x 15 cm subcutaneous cervical mass. The nonencapsulated mass was composed of interlacing and haphazard bundles of spindle cells on moderate to abundant loose myxomatous stroma. A moderate number of cells showed cross striations with minor nuclear variation and a low mitotic rate. Immunohistochemical staining for myoglobin, desmin, actin, vimentin, and S-100 was positive and negative for glial fibrillar antigen and keratin. Rhabdomyomas are rare benign tumors of striated muscle. Rhabdomyomas described previously in the vet...
Pieńkowska-Schelling A, Becker D, Bracher V, Pineroli B, Schelling C.Numerical and structural aberrations of chromosomes may cause malformations, embryonal losses and reduced or missing fertility. In male horses the fertility is rather well controlled through their semen evaluation. For mares there are no mandatory regulations which specify their use in a breeding programme. Therefore, mares with chromosomal aberrations, which exclude reproduction success may be chosen for breeding. The present case describes a horse, offically registered as a female, which was presented for a breeding exam. On this occasion, small and inactive ovaries were diagnosed. Although ...
Schuler G.The pituitary gonadotrophins follicle-stimulating hormone (FSH) and luteinizing hormone (LH) play a prominent role in the control of gonadal functions. Therefore, their use in the treatment of fertility disorders (e. g. anovulatory anestrus) as well as in biotechnology (e. g. superovulation, hormone programs for cycle synchronization) is of substantial interest. Preparations of FSH or LH are relatively expensive due to the laborious extraction from pituitary tissue and are therefore reserved for special indications. In primates and equids, the chorionic epithelium expresses an LH-like molecule...
Autry JM, Svensson B, Carlson SF, Chen Z, Cornea RL, Thomas DD, Valberg SJ.We have analyzed the enzymatic activity of the sarcoplasmic reticulum (SR) Ca2+-transporting ATPase (SERCA) from the horse gluteal muscle. Horses are bred for peak athletic performance yet exhibit a high incidence of exertional rhabdomyolysis, with elevated levels of cytosolic Ca2+ proposed as a correlative linkage. We recently reported an improved protocol for isolating SR vesicles from horse muscle; these horse SR vesicles contain an abundant level of SERCA and only trace-levels of sarcolipin (SLN), the inhibitory peptide subunit of SERCA in mammalian fast-twitch skeletal muscle. Here, we re...
Yang H, Ma YH, Li B, Dugarjaviin M.There is unique genetic information belonging to various kinds of living beings. Understanding of the formation process of organisms and a variety of vital movement is associated with the achievements of genome study. As horse has a notable health condition and great record of the genealogy in the world, thus it becomes a valuable model animal for studying life science. Despite of a late start, the map of the horse genome has undergone unprecedented expansion during the last few years. The current progresses of the horse genome, including genetic map, physical map, comparative genomic map, and...
King SS, Jones KL, Mullenix BA, Heath DT.Dopamine (DA) blockade during anestrus or early spring transition can facilitate ovarian recrudescence and advance the timing of the first ovulation of the season. Some laboratories have reported variable results using DA antagonists to stimulate follicular growth during the mid-portion of the anestrual period. Differences in DA antagonist efficacy may be due to the FSH secretory status of the anestrous mare and the presence or absence of functional ovarian FSH receptors. We hypothesize that direct ovarian dopaminergic input can affect follicular growth through regulation of FSH receptor (FSHr...
Hamilton NA, Tammen I, Raadsma HW.Angiotensin converting enzyme (ACE) is essential for control of blood pressure. The human ACE gene contains an intronic Alu indel (I/D) polymorphism that has been associated with variation in serum enzyme levels, although the functional mechanism has not been identified. The polymorphism has also been associated with cardiovascular disease, type II diabetes, renal disease and elite athleticism. We have characterized the ACE gene in horses of breeds selected for differing physical abilities. The equine gene has a similar structure to that of all known mammalian ACE genes. Nine common single nuc...
Premont A, Balthes S, Marr CM, Jeevaratnam K.Atrial fibrillation (AF) is the most common pathological arrhythmia in horses. Although it is not usually a life-threatening condition on its own, it can cause poor performance and make the horse unsafe to ride. It is a complex multifactorial disease influenced by both genetic and environmental factors including exercise training, comorbidities or ageing. The interactions between all these factors in horses are still not completely understood and the pathophysiology of AF remains poorly defined. Exciting progress has been recently made in equine cardiac electrophysiology in terms of diagnosis ...
Liu C, Lei H, Ran X, Wang J.The Guizhou pony (GZP) is an indigenous species of equid found in the mountains of the Guizhou province in southwest China. We selected four regions of the equine leukocyte antigen (ELA), including , , and and used them to assess the diversity of the major histocompatibility complex (MHC) class II gene using direct sequencing technology. had the lowest / ratio (0.560) compared with the other three loci, indicating that was conserved and could be conserved after undergoing selective processes. Nine , five , nine and seven codons were under significant positive selection at the antigen b...
Sellon DC, Walker KM, Russell KE, Perry ST, Fuller FJ.Equine infectious anemia virus (EIAV) is a lentivirus that replicates predominantly in mature tissue macrophages. Viral expression is strongly influenced by the state of differentiation of the host cell. While blood monocytes can be infected, viral transcription is limited until the cell differentiates into a mature macrophage. Activation of mature macrophages infected with EIAV might also alter viral expression, presumably through binding of cellular transcription factors to viral nucleic acid sequences within the long terminal repeat (LTR). Using DNA amplification techniques, we compared LTR...
Ginther OJ.The mechanism for selection of the future dominant or ovulatory follicle in mares involves a relatively abrupt separation in growth rates between the future dominant follicle and several subordinate follicles and is termed diameter deviation. The event is used to illustrate that a coordinated complex of many follicular, hormonal, and biochemical factors interact and interbalance during a single physiological mechanism. For example, a positive effect of follicle stimulating hormone (FSH) on development of all follicles during the growing phase can later involve a positive effect of luteinizing ...
Puff C, Herder V, Philipp A, Baumgärtner W.A 15-year-old Haflinger gelding presented with a mass in the left nictitating membrane. Two biopsies and the excised nictitating membrane were taken at different time points as a result of reoccurrence of the mass and submitted for histopathologic evaluation. The horse was euthanized as a result of poor prognosis following the reoccurrence of the mass after surgical removal. Histologically, the mass consisted of dilated, thin-walled vascular clefts and channels, lined by flattened to cuboidal endothelial cells with moderate cellular pleomorphism. There was up to 1 mitotic figure per high power...
Cook RF, Cook SJ, Even DL, Schaffer C, Issel CJ.Horse IL-7 (HIL-7) cDNA was isolated from adult lymph node tissue by reverse transcription polymerase chain reaction (RT-PCR) using oligonucleotide primers based on horse genomic sequences (The Broad Institute). In addition, to the full-length (FL) 531bp reading frame encoding 176 amino acids, shorter open-reading frames of 477, 396 and 264bp were also amplified. Nucleotide sequence analysis of these RT-PCR products demonstrated they were homologous except the shorter species were missing internal sequences consistent with multiple RNA splicing events. Consequently, the shorter open-reading fr...
