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.
Holden VR, Harty RN, Yalamanchili RR, O'Callaghan DJ.The complete nucleotide sequence of the inverted repeat component (IR; 12,776 bp each) of the genome of equine herpesvirus type 1 (EHV-1) has been determined. Transcription analyses have revealed that the EHV-1 IR sequence encodes at least 6 genes. In this report, we present the DNA sequence and transcriptional characterization of a gene (IR3) that maps entirely within the IR sequences. The IR3 open reading frame (ORF) is located between nucleotides (nt) 6123-6411 of the IR sequence and possesses an ORF of 95 amino acids. Interestingly, this ORF does not show homology to any known herpesvirus ...
Rønne M.After fluorouracil/5-bromodeoxyuridine synchronization and subsequent FPG-staining, the karyotype of 15 phenotypically normal horses displayed several breaks and gaps. Twelve bands 1q24, 4p12, 8q23, 11p12, 16q21, 17q21, 23q31, 23q32, Xp21, Xq22, Xq25 and Xq27 showed relatively frequent fragility. After thymidine/cytidine synchronization and subsequent GWL-banding the same horses display karyotypes without any fragility. Hence it is suggested that the above listed bands harbour folate and/or 5-bromodeoxyuridine sensitive fragile sites.
Zurkowski M, Kuryl J.A new genetic variant in the horse Pi system, designated Z2, was reported in Polish Arabs by using two-dimensional agarose polyacrylamide gel electrophoresis. The frequencies of Pi alleles F, G, L, L2, N, S, U, W, Z and Z2 were found to be 0.036, 0.005, 0.171, 0.013, 0.008, 0.237, 0.416, 0.003, 0.107 and 0.004 respectively.
Weber JA, Woods GL, Freeman DA, Vanderwall DK.Prostaglandin E2 (PGE2) bound specifically (P less than 0.001) to ampullary and isthmic tissue on Day 2 and Day 5 after ovulation. No significant differences (P greater than 0.8) were detected between Day 2 and Day 5 in the specific binding of ampullary or isthmic tissue. Significantly more (P less than 0.05) PGE2 bound specifically to ampullary versus isthmic tissue on both days. Detection of PGE2-specific binding in the oviductal isthmus on Day 2 and Day 5 indicates that the oviduct is responsive to PGE2 when it is capable of transporting equine embryos.
Ellegren H, Johansson M, Sandberg K, Andersson L.We have isolated equine microsatellites by screening a genomic library with (TG)n and (TC)n probes. TG microsatellites were found to be more abundant than TC repeats, with an estimated frequency of one per 100,000bp. Sequence analysis of eight TG-positive clones revealed varying structures of the repeat regions; perfect stretches of TG repeats, imperfect stretches of TG repeats and compound regions of TG and TC repeats. Five loci were analysed by PCR and showed extensive polymorphism; three to seven alleles and heterozygosities of 0.40-0.76 were observed when screening 20-30 unrelated individu...
Bowling AT, Nickel LS.Family data from Paso Fino horses support the existence of a new allele (Aabdf) in the A system of red cell alloantigens. Considering breeds throughout the world, the A system now consists of 13 alleles defined by reagents which serologically detect seven factors.
Lear TL, Trembicki KA, Ennis RB.Giemsa-11 (G-11) staining and in situ hybridization were used to identify the equine chromosome complement of horse x mouse somatic cell hybrids. The presence of horse chromosomes in somatic cell hybrids was determined by differential G-11 staining. The slides were then destained and hybridized with biotinylated total horse (Equus caballus) genomic DNA without suppression. Fluorescence detection permitted rapid confirmation of horse chromosomal DNA in the hybrid cells.
Naylor JM, Robinson JA, Crichlow EC, Steiss JE.Electromyography (EMG) was used to detect myotonic discharges in Quarter Horse breeding stock and to follow the results of mating horses with hyperkalemic periodic paralysis (HPP). The studies were performed on two brood mare farms. A total of six breeding stock showed myotonic discharges and 15 were nonmyotonic. Myotonic discharges were seen in five of six horses belonging to the blood line previously implicated as being predisposed to HPP. Two of these horses had shown clinical signs of HPP. Only one of 15 breeding horses unrelated to the HPP predisposed blood line showed myotonic discharges...
Chowdhary BP, Harbitz I, Davies W, Gustavsson I.In situ hybridization techniques were used to localize regionally the calcium release channel (CRC) gene on cattle and horse chromosomes, using a porcine CRC cDNA probe. In cattle, the hybridization signal peaked on the 18q23-q26 bands and in horse on the 10pter region. Previous studies have shown that the glucose phosphate isomerase (GPI) gene localizes at the same site in both species, indicating that the two loci are syntenic. As CRC and GPI are syntenic in human, pig and mouse, the present results in cattle and horse represent another example of synteny conservation in the evolution of mam...
Power MM, Gustavsson I, Switoński M, Plöen L.Synaptonemal complex analysis by electron microscopy of a trisomy 28 in a male horse demonstrated a trivalent or a bivalent plus a univalent in primary spermatocytes. Two of the chromosomes making up the trivalent were, most often, completely paired with each other and only partially paired or associated with the third one. Half of the spermatocytes analysed demonstrated heterologous pairing or association between the free axis of the trivalent and the sex bivalent. The pairings remained, to a large extent, into diakinesis-metaphase I. In most pachytene cells one autosomal bivalent showed prox...
Ellegren H, Andersson L, Johansson M, Sandberg K.A synthetic polynucleotide (TG)n was hybridized to equine DNA digested with HinfI and hypervariable hybridization patterns were obtained. Mendelian inheritance of these DNA fingerprinting patterns was confirmed by pedigree analysis. Estimates of the probabilities of identical band patterns in unrelated individuals of different breeds (Swedish Trotters, North Swedish Trotters, Thoroughbreds and Arabians) were in the range 1 x 10(-4) - 7 x 10(-6). The variability derived with the (TG)n probe in horses was higher than what we obtained with several other commonly used probes for DNA fingerprinting...
Felsburg PJ, Somberg RL, Perryman LE.This review describes the clinical, immunologic and pathologic features of two naturally-occurring models of severe combined immunodeficiency (SCID) in domestic animals that represent different forms of human SCID. Canine X-linked SCID (XSCID) has an X-linked recessive mode of inheritance and, as such, represents a model for the most common form of human SCID in the United States. Affected dogs have normal percentages of circulating B cells and low to normal percentages of phenotypically mature, but nonfunctional T cells. Severe combined immunodeficiency in the horse is an autosomal recessive ...
Browning GF, Chalmers RM, Fitzgerald TA, Corley KT, Campbell I, Snodgrass DR.Foal fecal group A rotavirus strains were characterized by electropherotype, serotype, and subgroup and shown to be distinctly different from rotaviruses of other mammals. Of 86 strains that were electropherotyped, 98% had similar profiles, with gene segments 3 and 4 close together and segments 7, 8, and 9 widely spaced. Of 70 strains that had sufficient detectable VP7 antigen to be serotyped by enzyme-linked immunosorbent assays (ELISAs), 63% were serotype G3 (39% were subtype G3A and 24% were subtype G3B), 4% were serotype G13, and 33% were untypeable. Serotypes G1, G2, G4, G5, G6, G9, G10, ...
Schuberth HJ, Anders I, Pape U, Leibold W.The cells of 60 randomly selected Hannoveranian warm-blooded horses were subjected to one-dimensional isoelectric focusing and immunoblotting with a cross-reacting monoclonal antibody (Bo 1) recognizing bovine class I antigens. The banding patterns were correlated with the serologically defined specificities of the ELA-A locus. ELA-A2 was correlated with four bands, while ELA-A5, ELA-W18, ELA-A6, ELA-A14 and ELA-A9 were correlated with a single band each. The complexity of the pattern and additional polymorphic bands which could not be correlated to any of the known ELA specificities may indic...
Endo A, Pecoraro R, Sugita S, Nerome K.The nucleotide and deduced amino acid sequences of the haemagglutinin genes coding for the HA 1 domain of H3N8 equine influenza viruses isolated over wide regions of the world were analyzed in detail to determine their evolutionary relationships. We have constructed a phylogenetic model tree by the neighbour-joining method using nucleotide sequences of 15 haemagglutinin genes, including those of five viruses determined in the present study. This gene tree revealed the existence of two major evolutionary pathways during a twenty five-year period between 1963 to 1988, and each pathway appeared t...
Rudolph JA, Spier SJ, Byrns G, Hoffman EP.A genetic disease observed in certain Quarter horses is hyperkalaemic periodic paralysis (HYPP). This disease causes attacks of paralysis which can be induced by ingestion of potassium. Recent studies have shown that HYPP in humans is due to single base changes within the adult skeletal muscle sodium channel gene. A large Quarter horse pedigree segregating dominant HYPP was studied to determine if mutations of the sodium channel gene are similarly responsible for HYPP in horses. We used cross-species, PCR-mediated, cDNA cloning and sequencing of the horse adult skeletal muscle sodium channel a...
García-Tamayo J.Clinical findings on Venezuelan Equine Encephalitis virus infection and the teratogenic effects of several Togaviruses are described. Similarities between the intrauterine alterations induced by Venezuelan Equine Encephalitis virus and rubella virus are pointed out. Findings described by Wenger in 1967 were those of massive cerebral necrosis in fetuses of women presumably suffering of encephalitis and they are commented along with the development of an animal experimental model at the end of 1970-1980. Pathogenesis of the intrauterine infection seemed to be related to changes in the placental ...
Valberg SJ, Cardinet GH, Carlson GP, DiMauro S.A polysaccharide storage myopathy is described in nine Quarterhorses, Quarterhorse crossbreds, American Paints and Appaloosa horses which had a history of recurrent exertional rhabdomyolysis. Muscle biopsies were characterized by high muscle glycogen concentrations with up to 5% of type 2 muscle fibers containing inclusions which stained positively with the periodic acid Schiff (PAS) stain. The inclusions were classified as an acid mucopolysaccharide, based on their histochemical staining characteristics. Ultrastructural studies revealed that the inclusions were composed of beta glycogen parti...
Rae C, Board PG, Kuchel PW.In mammalian red blood cells the metabolism of methylglyoxal, and some alpha-ketoaldehydes, takes place via two, generally, highly active enzymes, glyoxalase 1 and 2. The 1H NMR spin-echo spectra of horse erythrocytes, and the various reactants in the glyoxalase system, were characterized as a prelude to obtaining series of spectra in time courses of methylglyoxal metabolism. We characterized the kinetics of the enzyme system in red cells from a normal horse and also from one which had very low activity of glyoxylase 2. The kinetics of the reaction scheme, with methylglyoxal as the starting su...
Simpson KS, Adams MH, Behrendt-Adam CY, Baker CB, McDowell KJ.For development to proceed normally, the appropriate genes must be expressed in the correct tissues and in the correct time frame. Knowledge of gene expression during development provides information about the changes taking place within the conceptus as well as possible reasons for pregnancy failure. However, little is known about gene expression during development in the equine conceptus. In this study, we examined differences in gene expression between day 12 and day 15 equine conceptuses by suppression subtractive hybridization. This technique was used to isolate transcripts that are more ...
Giles C, Vanniasinkam T, Barton M, Mahony TJ.Equine adenovirus 2 (EAdV-2) is one of two serotypes of adenoviruses known to infect equines. Initial studies did not associate EAdV-2 infections with any specific clinical syndromes, although more recent evidence suggests that EAdV-2 may be associated with clinical and subclinical gastrointestinal infections of foals and adults respectively. In contrast, Equine adenovirus 1 is well recognised as a pathogen associated with upper respiratory tract infections of horses. In this study the complete genome sequence of EAdV-2 is reported. As expected, genes common to the adenoviruses were identified...
Black JA, Leaf G.1. The effects of cyanogen bromide on horse-heart cytochrome c and horse-heart myoglobin have been investigated. Cytochrome c yielded four fragments, of which two were haemopeptides. The two colourless peptides had amino acid compositions corresponding to those that are expected, on the basis of the sequence proposed for horse-heart cytochrome c by Margoliash, Smith, Kreil & Tuppy (1961), from cleavage at both methionine residues. Of the two haemopeptides, one was isolated and shown to be that derived from cleavage at only one methionine residue, that nearer to the C-terminus of the peptid...
Possessing high meat and dairy productivity and good reproductive and adaptive qualities to year-round grazing, the Kushum breed plays an exceptional role in the improvement of productive qualities in horse herding in Kazakhstan and the former Soviet republics. The aim of the study was to develop breeding methods for creating new highly productive breeding lines for the Kushum breed horses. The leading method was linebreeding, which is based on the systematic use of remarkable animals, the offspring of which will accumulate and develop all the desired qualities and traits. The practical signif...
Koyago M, Nakada K, Tsunoda N, Moriyoshi M, Sawamukai Y.The morphology of spermatozoa of modern Thoroughbred stallions in Japan was investigated during the breeding season. A total of 299 semen samples were collected from the penises of 16 stallions immediately after service. The rate of abnormalities in sperm heads and tails, spermatozoa with cytoplasmic droplets and slides with medusa cells to total observed slides in each stallion were 3.9 +/- 2.1%, 11.5 +/- 5.9%, 2.4 +/- 2.6% and 20.1%, respectively. The values for the area, length, width and aspect ratio of the stallion sperm head were 12.54 +/- 1.34 microm(2), 5.93 +/- 0.40 microm, 2.69 +/- 0...
Takai S, Ohashi M, Suzuki Y, Sasaki Y, Kakuda T, Broens EM, Wagenaar JA, van Duijkeren E.Clinical samples from 123 foals with suspected rhodococcosis submitted to the Veterinary Microbiological Diagnostic Centre of the Faculty of Veterinary Medicine between 1993 and 2006 were tested for the presence of the virulence gene vapA. Of the 123 samples, 120 were vapA-positive and 3 vapA-negative Rhodococcus equi were isolated. The 120 vapA-positive R. equi were isolated from 70 tracheal wash, 19 lung tissues, 7 lymph nodes, 6 synovial fluids, 13 abscesses or pus and single isolates from the uterus, gut, cerebrospinal fluid, abdomen fluid and faeces. Of the 120 isolates, 46 were from Dutc...
Larrasa J, Garcia A, Ambrose NC, Alonso JM, Parra A, de Mendoza MH, Salazar J, Rey J, de Mendoza JH.Dermatophilus congolensis is the pathogenic actinomycete that causes dermatophilosis in cattle, lumpy wool in sheep and rain scald in horses. Phenotypic variation between isolates has previously been described, but its genetic basis, extent and importance have not been investigated. Standard DNA extraction methods are not always successful for D. congolensis due to its complex life cycle, one stage of which is encapsulated. Here we describe the development of rapid and reliable DNA extraction and random amplified polymorphic DNA (RAPD) methods that can be used for genotyping D. congolensis fie...
Liu C, Cook SJ, Craigo JK, Cook FR, Issel CJ, Montelaro RC, Horohov DW.Unlike other lentiviruses, EIAV replication can be controlled in most infected horses leading to an inapparent carrier state free of overt clinical signs which lasts for many years. While the resolution of the initial infection is correlated with the appearance of virus specific cellular immune responses, the precise immune mechanisms responsible for control of the infection are not yet identified. Since the virus undergoes rapid mutation following infection, the immune response must also adapt to meet this challenge. We hypothesize that this adaptation involves peptide-specific recognition sh...
Ghosh S, Kjöllerström J, Metcalfe L, Reed S, Juras R, Raudsepp T.We present cytogenetic and genotyping analysis of a Thoroughbred foal with congenital neurologic disorders and its phenotypically normal dam. We show that the foal has non-mosaic trisomy for chromosome 26 (ECA26) but normal 2n = 64 diploid number because two copies of ECA26 form a metacentric derivative chromosome der(26q;26q). The dam has normal 64,XX karyotype indicating that der(26q;26q) in the foal originates from errors in parental meiosis or post-fertilization events. Genotyping ECA26 microsatellites in the foal and its dam suggests that trisomy ECA26 is likely of maternal origin and tha...
Yilma T, Perryman LE, McGuire TC.The results of a study on the induction of IFN-alpha, IFN-beta, and IFN-gamma in normal and SCID foals showed a deficiency of IFN-gamma but not IFN-beta in SCID foals. The ability of SCID mononuclear cells to produce IFN-alpha in response to poly I:C but not to NDV may indicate a partial deficiency of IFN-alpha in SCID foals. The deficiency of IFN-gamma and presence of IFN-beta in SCID foals supports the classification of IFN-gamma and IFN-beta as immune and nonimmune interferons, respectively. Furthermore, the deficiency of IFN-gamma in SCID foals may in part explain the high susceptibility t...
Tompkins D, Hudgens E, Horohov D, Baldwin CL.This report describes the initial cloning and characterization of the equine interleukin-17 (IL-17) expressed gene sequence from mRNA obtained from equine intestinal tissue and interleukin-23 (IL-23) expressed gene sequence from mRNA obtained from equine peripheral blood mononuclear cells. Equine IL-17 has 462 nucleotides in the translated region, determined by homology with known human and mouse sequences, and shares 84% and 75% identity, respectively. For the deduced amino acid sequences, the identity with human and mouse is 76% and 70%. Equine IL-23 has 579 nucleotides in the translated reg...
Sonea IM, Wilson DV, Bowker RM, Robinson NE.Tachykinins, of which substance P (SP) is the prototype, are neuropeptides which are widely distributed in the nervous systems. In the equine gut, SP is present in enteric nerves and is a powerful constrictor of enteric muscle; in other species, SP is also known to have potent vasodilatory and pro-inflammatory effects. The specific effects of SP are determined by the subtype of receptor present in the target tissue. There are 3 known subtypes of tachykinin receptors, distinguished by their relative affinities for SP and other tachykinins. The distribution of SP binding sites in the equine pelv...
Arias KD, Cervantes I, Gutiérrez JP.In genetic evaluation of horses, the genetic trend does not correspond into a phenotypic trend when using ranking as a phenotype due to its uniform distribution, and some other effects might be absorbing that trend. From a founder population, a further four discrete generations of 100 individuals were simulated under random mating. Then, ten additional discrete generations were simulated by selecting the best 10% of the animals. Likewise, an underlying variable with heritability 0.1 or 0.2, affected by an event environmental influence, generation and permanent environment, was simulated to est...
Hurlimann J, Darling H.The synthesis of immunoglobulins by the salivary glands from eight different species was studied. It has been demonstrated that salivary glands from the cow, horse, sheep, pig, rat and guinea-pig preferentially synthesize a fast migrating immunoglobulin which seems to be analogous to IgA. In three of the species, the cow, sheep and pig, the IgA-like component cross-reacts with human IgA. The IgA synthesized by the salivary glands from the rat cross-reacts with the mouse IgA. When one compares the salivary IgA from the cow, horse, sheep, pig and rat with the IgA synthesized by the lymph nodes,...
Hirsh DC, Kirkham C, Wilson WD.Fifteen isolates of Escherichia coli obtained from the blood and tissues of septic foals had plasmid DNA of size ranging from 2.5 to 93 megadaltons. These isolates grew in normal equine serum (serum resistant), a trait previously documented to be expressed by isolates obtained from blood and tissues of septic foals, but not by isolates obtained from the feces of clinically normal horses. Of these isolates, 3 contained conjugal plasmids that encoded resistance to multiple antimicrobial agents linked to serum resistance and, in 1 isolate, to production of aerobactin as well. Serum resistance and...
Mendoza L, Piquemal D, Lejeune JP, Vander Heyden L, Noguier F, Bruno R, Sandersen C, Serteyn D.Osteochondrosis (OC) is a developmental disease in horses which has a significant impact on the horse's welfare and performance. The early disturbance in the process of endochondral ossification progresses to inflammatory and repair processes in older horses. Previously, differentially expressed genes in leukocytes of OC-affected horses have been identified. The aim of the present study is to detect age-related changes in these differentially expressed genes. Methods: The expression of OC-related genes was analysed by real-time PCR and subsequent statistical analysis (ΔΔCT) in the leukocytes...
Corbin LJ, Blott SC, Swinburne JE, Vaudin M, Bishop SC, Woolliams JA.We have used linkage disequilibrium (LD) to identify single nucleotide polymorphisms (SNPs) on the Illumina Equine SNP50 BeadChip, which may be incorrectly positioned on the genome map. A total of 1201 Thoroughbred horses were genotyped using the Illumina Equine SNP50 BeadChip. LD was evaluated in a pairwise fashion between all autosomal SNPs, both within and across chromosomes. Filters were then applied to the data, firstly to identify SNPs that may have been mapped to the wrong chromosome and secondly to identify SNPs that may have been incorrectly positioned within chromosomes. We identifie...
Okada CTC, Kaps M, Reichart U, Walter I, Gautier C, Aurich J, Aurich C.While detrimental effects of reduced plasma progesterone concentration in the early luteal phase on conceptus development in horses have recently been demonstrated, there is no information on associated effects on the endometrium, allantochorion (AC), and chorionic girdle (CG) in this species. We hypothesised that reduced early postovulatory progesterone concentration in pregnant horses is detrimental to endometrial function and development of the embryonic membranes and is an underlying cause of delayed conceptus development. After insemination and ovulation, mares (n = 11) were assigned to...
Machado FB, de Vasconcellos Machado L, Bydlowski CR, Bydlowski SP, Medina-Acosta E.Validation of parentage and horse breed registries through DNA typing relies on estimates of random match probabilities with DNA profiles generated from multiple polymorphic loci. Of the twenty-seven microsatellite loci recommended by the International Society for Animal Genetics for parentage testing in Thoroughbred horses, eleven are located on five chromosomes. An important aspect in determining combined exclusion probabilities is the ascertainment of the genetic linkage status of syntenic markers, which may affect reliable use of the product rule in estimating random match probabilities. I...
The Journal of hereditySeptember 1, 1983
Volume 74, Issue 5 361-364 doi: 10.1093/oxfordjournals.jhered.a109811
Andersson L, Sandberg K, Adalsteinsson S, Gunnarsson E.Three previously described electrophoretic phenotypes of mitochondrial glutamate oxaloacetate transaminase (GOTM) in horse leukocytes are shown to be controlled by two codominant alleles at a single autosomal locus. The GOTM locus is linked to the serum esterase locus (Es), as no recombination between these loci was observed among 16 informative offspring in one sire family. The results assign GOTM to equine linkage group (LG) II. The hypothesis that a part of LG II (e-Es) shares homologies with mouse chromosome 8 is thus confirmed, as the murine homologue of GOTM is located within the cluster...
Gupta S, Vohra S, Sethi K, Gupta S, Kumar S, Kumar R.The kinetoplastid protozoan parasite, Trypanosoma evansi causes a fatal disease condition known as Surra in equines throughout the globe. Disease condition being acute in nature, entrust a huge economic and health impact on the equine industry. Till date, quinapyramine methyl sulphate (QPS) is the first line of treatment and a panacea for the T. evansi infection in equines. Still after the >70 years of its discovery, there is no clue about the mode of action of QPS in T. evansi. The establishment of in vitro cultivation of T. evansi in HMI-9 media has provided opportunity to study the alte...
Amri H, Gaillard JL, al-Timimi I, Silberzahn P.Mare granulosa cells and cyclic corpus luteum microsomes are reported to aromatize 19-norandrogens more efficiently than androgens. However, 16 alpha-hydroxytestosterone and epitestosterone were not aromatized by the equine corpus luteum microsomal estrogen synthetase. These results indicate that the equine aromatase system would be different from the human placental microsomal estrogen synthetase, which aromatizes 16 alpha-hydroxyandrogens and epitestosterone but not 19-norandrogens. Furthermore, our data show that the rates of aromatization of androgens and 19-norandrogens were not additive ...
Moore BD, Balasuriya UB, Nurton JP, McCollum WH, Timoney PJ, Guthrie AJ, MacLachlan NJ.To compare growth characteristics of strains of equine arteritis virus (EAV) of differing virulence to horses in rabbit kidney (RK)-13 cells and equine endothelial cells (EECs) cultured from the pulmonary artery of a foal. Methods: 13 strains of EAV, including 11 field isolates of differing virulence to horses; the highly virulent, horse-adapted Bucyrus strain; and the modified-live virus (MLV) vaccine derived from it. Methods: The growth characteristics of the 13 strains were compared in EECs and RK-13 cells. Viral nucleoprotein expression, cytopathogenicity, and plaque size were compared to ...
Fraser RS, Arroyo LG, Meyer A, Lillie BN.Collagenous lectins are a family of soluble pattern recognition receptors that play an important role in innate immune resistance to infectious disease. Through recognition of carbohydrate motifs on the surface of pathogens, some collagenous lectins can activate the lectin pathway of complement, providing an effective means of host defense. Genetic polymorphisms in collagenous lectins have been shown in several species to predispose animals to a variety of infectious diseases. Infectious diseases are an important cause of morbidity in horses, however little is known regarding the role of equin...
Levene A.In man the epidermis is the final destination for most of the melanocytes which are of neural crest origin, and they migrate to a variety of sites. Dermal melanocytic distribution, conspicuous in some lower animals, has a very restricted normal distribution in man, and of the variety of anomalies which exist the blue naevus is the most frequently encountered. It is comparable to the common melanocytoma of dog and hamster. More widespread dermal melanocytoses are rare, and a unique case in which death from melanoma supervened, recently recorded by the author, is an example of a syndrome the onl...
Kuiper H, Blum N, Distl O.In a 1.5-year-old Oldenburg horse, a clitoris-like structure instead of a penis was identified in the prepuce. The external genital organs did not show any abnormalities at visual inspection except that exteriorization of the penis was not possible, not even under general anesthesia. The horse's owner observed a continuous dripping of urine and a tendency to mild colics beginning 2 weeks after birth. Testosterone concentration was 0.01 ng/ml and therefore under the threshold for geldings, and the horse did not respond to the application of gonadotropin-releasing hormone (GnRH). The inner genit...
Rodríguez N, Whitfield-Cargile CM, Chamoun-Emanuelli AM, Hildreth E, Jordan W, Coleman MC.The nasopharyngeal bacterial and fungal microbiota of normal horses and those with nasopharyngeal cicatrix syndrome (NCS) are unknown. Objective: To describe the microbiota from nasopharyngeal washes of healthy horses and of horses acutely affected with NCS. Methods: Twenty-six horses acutely affected with NCS horses and 14 unaffected horses. Methods: Prospective, observational cohort study. Horses were recruited by investigators through personal communications in central Texas. Bacterial (16s RNA) and fungal (internal transcribed spacer) microbiota from nasopharyngeal washes were evaluated. P...
Ginther OJ, Utt MD, Beg MA, Gastal EL, Gastal MO.The negative effect of estradiol-17beta (E2) on LH, based on exogenous E2 treatments, and the reciprocal effect of LH on endogenous E2, based on hCG treatments, were studied throughout the ovulatory follicular wave during a total of 103 equine estrous cycles in seven experiments. An initial study developed E2 treatment protocols that approximated physiologic E2 concentrations during the estrous cycle. On Day 13 (ovulation = Day 0), when basal concentrations of E2 and LH precede the ovulatory surges, exogenous E2 significantly depressed LH concentrations to below basal levels. Ablation of all f...
Messier PE, Drouin R, Richer CL.We present an immunochemical technique for the detection of 5-bromo-2'-deoxyuridine (BrdU) incorporated discontinuously into the chromosomal DNA. A monoclonal anti-BrdU antibody and a protein A-gold complex were used to produce chromosome banding of human and equine chromosomes, specific for electron microscopy (EM). Well-defined bands, symmetry of sister chromatids, concordance between homologues, and band patterns similar to those observed by light microscopy facilitate chromosome identification and karyotyping. From prophase to late metaphase, chromosomes condense and bands appear to fuse. ...
Anzai T, Timoney JE, Kuwamoto Y, Wada R, Oikawa M, Higuchi T.To develop polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis for molecular typing of strains of Streptococcus zooepidemicus and to use the new typing method to analyze a collection of isolates from the respiratory tract of Thoroughbreds. Methods: 10 strains of S zooepidemicus, 65 isolates from the respiratory tract of 9 yearlings following long distance transportation, and 89 isolates from tracheal aspirates of 20 foals with pneumonia. Methods: Phenotypic variations in the SzP protein were detected by western immunoblot analysis. Using PCR-RFLP analysis, ge...