Laboratory methods in equine research encompass a variety of techniques and procedures used to analyze biological samples from horses to study health, disease, genetics, and physiology. These methods include hematological analyses, biochemical assays, molecular biology techniques, and microbiological cultures. Commonly utilized laboratory techniques involve blood tests for complete blood count (CBC) and serum chemistry, polymerase chain reaction (PCR) for genetic and infectious disease studies, and enzyme-linked immunosorbent assays (ELISA) for detecting specific proteins or antibodies. These methods provide valuable data that contribute to understanding equine health and disease mechanisms. This page compiles peer-reviewed research studies and scholarly articles that explore the application, development, and outcomes of laboratory methods in the context of equine research.
Hinchcliff KW, Sams RA.To determine the effect of administration of commercially available sodium bicarbonate (NaHCO3) on carbon 13 (13C) isotopic enrichment of carbon dioxide (CO2) in serum of horses. Methods: 7 healthy Thoroughbreds. Methods: Sodium bicarbonate (450 g) was administered via nasogastric intubation to horses. Horses had been fed a diet obtained from the same source and had access to water from the same source for 3 months before the study. Blood samples were collected immediately before and at 2, 4, 6, and 24 hours after administration of NaHCO3. The concentration of total CO2 in serum was measured b...
Domeneghini C, Radaelli G, Arrighi S, Bosi G, Dolera M.The small and large intestine of adult horses were histochemically and immunohistochemically investigated in order to evidence components of the intramural nervous system. The general structural organization of the intramural nervous system was examined by using Nissl-thionin staining as well as the anti-neurofilament 200 (NF200) immunoreaction, which demonstrated the presence of neurons in the submucous as well as myenteric plexuses. The additional presence of subserosal ganglia was shown in the large intestine. Acetylcholinesterase (AChEase) activity was observed in both the submucous and my...
Hines R, Sorensen BR, Shea MA, Maury W.Binding of the transcription factor PU.1 to its DNA binding motif regulates the expression of a number of B-cell- and myeloid-specific genes. The long terminal repeat (LTR) of macrophage-tropic strains of equine infectious anemia virus (EIAV) contains three PU.1 binding sites, namely an invariant promoter-proximal site as well as two upstream sites. We have previously shown that these sites are important for EIAV LTR activity in primary macrophages (W. Maury, J. Virol. 68:6270-6279, 1994). Since the sequences present in these three binding motifs are not identical, we sought to determine the r...
Takahashi T, Yawata M, Raudsepp T, Lear TL, Chowdhary BP, Antczak DF, Kasahara M.In rodents, the Ly49 family encodes natural killer (NK) receptors interacting with classical MHC class I molecules, whereas the corresponding receptors in primates are members of the killer cell immunoglobulin-like receptor (KIR) family. Recent evidence indicates that the cattle, domestic cat, dog, and pig have a single LY49 and multiple KIR genes, suggesting that predominant NK receptors in most non-rodent mammals might be KIR. Here, we show that the horse has at least six LY49 genes, five with an immunoreceptor tyrosine-based inhibition motif (ITIM) and one with arginine in the transmembrane...
Bosken JM, Lehner AF, Hughes CG, Woods WE, Camargo FC, Harkins JD, Boyles J, Tobin T.Isoxsuprine is used to treat navicular disease and other lower-limb problems in the horse. Isoxsuprine is regulated as a class 4 compound by the Association of Racing Commissioners, International (ARCI) and, thus, requires regulatory monitoring. A gas chromatography-mass spectrometry method utilizing electron impact ionization was developed and validated for the quantitation of isoxsuprine in equine plasma or equine urine. The method utilized robotic solid-phase extraction and tri-methyl silyl ether products of derivatization. Products were bis-trimethylsilyl (TMS) isoxsuprine and tris-TMS rit...
Yang F, Fu B, O'Brien PC, Nie W, Ryder OA, Ferguson-Smith MA.We have made a complete set of painting probes for the domestic horse by degenerate oligonucleotide-primed PCR amplification of flow-sorted horse chromosomes. The horse probes, together with a full set of those available for human, were hybridized onto metaphase chromosomes of human, horse and mule. Based on the hybridization results, we have generated genome-wide comparative chromosome maps involving the domestic horse, donkey and human. These maps define the overall distribution and boundaries of evolutionarily conserved chromosomal segments in the three genomes. Our results shed further lig...
Yang F, Fu B, O'Brien PC, Robinson TJ, Ryder OA, Ferguson-Smith MA.Complete sets of chromosome-specific painting probes, derived from flow-sorted chromosomes of human (HSA), Equus caballus (ECA) and Equus burchelli (EBU) were used to delineate conserved chromosomal segments between human and Equus burchelli, and among four equid species, E. przewalskii (EPR), E. caballus, E. burchelli and E. zebra hartmannae (EZH) by cross-species chromosome painting. Genome-wide comparative maps between these species have been established. Twenty-two human autosomal probes revealed 48 conserved segments in E. burchelli. The adjacent segment combinations HSA3/21, 7/16p, 16q/1...
Ward TL, Valberg SJ, Lear TL, Guérin G, Milenkovic D, Swinburne JE, Binns MM, Raudsepp T, Skow L, Chowdhary BP, Mickelson JR.Comparative biochemical and histopathological data suggest that a deficiency in the glycogen branching enzyme (GBE) is responsible for a fatal neonatal disease in Quarter Horse foals that closely resembles human glycogen storage disease type IV (GSD IV). Identification of DNA markers closely linked to the equine GBE1 gene would assist us in determining whether a mutation in this gene leads to the GSD IV-like condition. FISH using BAC clones as probes assigned the equine GBE1 gene to a marker deficient region of ECA26q12-->q13. Four other genes, ROBO2, ROBO1, POU1F1, and HTR1F, that flank GB...
Gustafson AL, Tallmadge RL, Ramlachan N, Miller D, Bird H, Antczak DF, Raudsepp T, Chowdhary BP, Skow LC.A physical map of ordered bacterial artificial chromosome (BAC) clones was constructed to determine the genetic organization of the horse major histocompatibility complex. Human, cattle, pig, mouse, and rat MHC gene sequences were compared to identify highly conserved regions which served as source templates for the design of overgo primers. Thirty-five overgo probes were designed from 24 genes and used for hybridization screening of the equine USDA CHORI 241 BAC library. Two hundred thirty-eight BAC clones were assembled into two contigs spanning the horse MHC region. The first contig contain...
Kollias-Baker C, Maxwell L, Stanley S, Boone T.Cocaine is a naturally occurring alkaloid that is commonly abused by human-beings for its psychostimulatory effects. Occasionally, very small concentrations (i.e. <100 ng/mL) of the primary cocaine metabolite, benzoylecgonine (BZE) have been detected in urine collected from horses competing in athletic events. In this study urine samples, collected from four horses following the administration of 2.5 and 20 mg of cocaine sublingually and 50 mg of cocaine intravenously, were analyzed for the presence of cocaine and/or its metabolites by enzyme-linked immunosorbent assay (ELISA) and gas chrom...
Frazer KA, Tao H, Osoegawa K, de Jong PJ, Chen X, Doherty MF, Cox DR.Cross-species DNA sequence comparison is a fundamental method for identifying biologically important elements, because functional sequences are evolutionarily conserved, wheres nonfunctional sequences drift. A recent genome-wide comparison of human and mouse DNA discovered over 200,000 conserved noncoding sequences with unknown function. Multispecies DNA comparison has been proposed as a method to prioritize these conserved noncoding sequences for functional analysis based on the hypothesis that elements present in many species are more likely to be functional than elements present in limited ...
Cowley AB, Lukat-Rodgers GS, Rodgers KR, Benson DR.N-Acetylmicroperoxidase-8 (1) contains heme and residues 14-21 of horse mitochondrial cytochrome c (cyt c). The two thioether bonds linking protein to heme in cyt c are present in 1, and the native axial ligand His-18 remains coordinated to iron. As an approach to probing structural or functional roles played by the double covalent heme-protein linkage in cyt c, we have initiated a study in which the properties of 1 are compared with those of a synthetic mono-His coordinated heme peptide containing a single covalent linkage (2). One consequence of the greater conformational restriction imposed...
Balasuriya UBR, Hedges JF, Smalley VL, Navarrette A, McCollum WH, Timoney PJ, Snijder EJ, MacLachlan NJ.Equine arteritis virus (EAV) causes a persistent infection of the reproductive tract of carrier stallions. The authors determined the complete genome sequences of viruses (CW96 and CW01) that were present 5 years apart in the semen of a carrier stallion (CW). The CW96 and CW01 viruses respectively had only 85.6 % and 85.7 % nucleotide identity to the published sequence of EAV (EAV030). The CW96 and CW01 viruses had two 1 nt insertions and a single 1 nt deletion in the leader sequence, and a 3 nt coding insertion in ORF1a; thus their genomes included 12 708 nt as compared to the 12 704 nt in EA...
Quinlivan M, Cullinane A, Nelly M, Van Maanen K, Heldens J, Arkins S.Four seronegative foals aged 6 to 7 months were exposed to an aerosol of influenza strain A/Equi/2/Kildare/89 at 10(6) 50% egg infective doses (EID(50))/ml. Nasopharyngeal swabs were collected for 10 consecutive days after challenge. Virus isolation was performed in embryonated eggs, and the EID(50) was determined for all positive samples. The 50% tissue culture infective dose was determined using Madin-Darby canine kidney (MDCK) cells. Samples were also tested by an in vitro enzyme immunoassay test, Directigen Flu A, and by reverse transcription-PCR (RT-PCR) using nested primers from the nucl...
Jolly RD, Palmer DN, Dalefield RR.Analytical studies of three lipopigments show that much can be achieved. Lipopigment from ovine ceroid-lipofuscinosis is composed of discrete protein and lipid molecules in orderly arrays and lipid peroxidation is not involved in its formation. Subunit c of mitochondrial ATP synthase accounts for approximately 50% of accumulated material and is specific to the disease process in this and other forms of the disease. Lipofuscin from bovine heart was mostly soluble and also contained discrete proteins, lipids and metals. Equine thyroid lipofuscin was less soluble but also had a relatively high pr...
Moussa M, Tremoleda JL, Duchamp G, Bruyas JF, Colenbrander B, Bevers MM, Daels PF.The aim of this study was to evaluate the viability (percentage of dead cells) and the incidence of DNA fragmentation of horse embryos after storage in three different media at 5 degrees C for 6 and 24 h. Forty embryos were stored in Emcare Holding Solution for 6 and 24 h, in Hams'F10 or Vigro Holding Plus for 24 h at 5 degrees C (n = 9-10 per group) and 10 embryos were evaluated immediately after collection. First, embryos were stained, immediately after collection or following storage, to detect dead cells (DAPI) and, subsequently, DAPI-stained embryos were fixed and stained to detect DNA fr...
Carstanjen B, Amory H, Youssao I, Remy B.The purpose of this study was to validate an equine-specific osteocalcin (OC) radioimmunoassay (RIA) for use in donkeys and to establish age-related changes in serum OC concentrations in healthy donkeys. Serial dilutions of donkey serum showed parallelism with standard curves obtained with the equine-specific OC RIA. There was a tight linear regression between donkey serum OC values obtained with the equine specific OC RIA and a commercially available bovine-specific OC RIA. Serum OC levels of 27 healthy donkeys, analysed with the equine-specific OC RIA, showed a tight negative logarithmic reg...
Luo Y, Rudy JA, Uboh CE, Soma LR, Guan F, Enright JM, Tsang DS.The method describes quantification and confirmation of flunixin in equine plasma by liquid chromatography-quadrupole time-of-flight mass spectrometry (LC/Q-TOF/MS/MS). Samples were screened by enzyme-linked immunosorbent assay (ELISA) and only those samples presumptively declared positive were subjected to quantification and confirmation for the presence of flunixin by this method. The method is also readily adaptable to instrumental screening for the analyte. Flunixin was recovered from plasma by liquid-liquid extraction (LLE). The sample was diluted with 2 ml saturated phosphate buffer (pH ...
Moore JN, Barton MH.Although recognition of clinical signs of endotoxemia is not difficult, determining the underlying cause for the development of endotoxemia may be a challenging task. For this reason, importance must be placed on performance of a thorough physical examination, attention to detail, and determination of whether or not surgical intervention is required. In most instances, a definitive diagnosis may require repeated examinations and laboratory work. In the meantime, affected animals require treatment for endotoxemia, with the aim being to reduce the duration of endotoxemia, prevent the interaction...
Farber CR, Medrano JF.In this study the flanking sequences of 1534 horse microsatellites were used in a BLAST search to identify putative human-horse homologies. BLAST searches revealed 129 flanking sequences with significant blastn matches [alignment scores (S) > or = 60 and sum probability values (E) < or = 3.0E-6], also, 25 of these produced significant blastx matches. To provide a reference point in the human genome the flanking sequences with matches were subjected to a BLAT search of the University of California Santa Cruz (UCSC) human genome assembly (July 2003 freeze). Eighty-three of the flanking seq...
Johnson A, Smith R, Saxne T, Hickery M, Heinegård D.Previous experiments have shown that addition of fragmented fibronectin can induce cartilage chondrolysis. In this study we investigated the fate of the collagen- and cell-binding molecules Cartilage oligomeric matrix protein (COMP) and chondroadherin. Methods: Equine articular cartilage explants were stimulated with the C-terminal and the N-terminal heparin-binding fragments of fibronectin respectively, and the conditioned media were analysed by both quantitative (ELISA) and qualitative (mass spectrometry, Western blots) methods. Results: Both COMP and chondroadherin were released in a dose-d...
van Ginneken MM, Keizer HA, Wijnberg ID, van Dam KG, Schaart G, de Graaf-Roelfsema E, van der Kolk JH, van Breda E.To investigate whether protein kinase C (PKC) isoforms are expressed in equine skeletal muscle and determine their distribution in various types of fibers by use of immunofluorescence microscopy. Methods: 5 healthy adult Dutch Warmblood horses. Methods: In each horse, 2 biopsy specimens were obtained from the vastus lateralis muscle. Cryosections of equine muscle were stained with PKC isoform (alpha, beta1, beta2, delta, epsilon, or zeta)-specific polyclonal antibodies and examined by use of a fluorescence microscope. Homogenized muscle samples were evaluated via western blot analysis. Results...
Sato F, Yamashita S, Kugo T, Hasegawa T, Mitsui I, Kijima-Suda I.To determine the full-length complementary DNA (cDNA) sequence of equine erythropoietin (EPO) and to develop region-specific antibodies to differentiate equine EPO (eEPO) and human EPO (hEPO). Methods: RNA and lysate extracted from renal tissues of an adult Thoroughbred. Methods: Full-length cDNA was determined by use of a reverse transcriptase-polymerase chain reaction assay and a rapid amplification of cDNA ends method. The deduced amino acid sequence was compared with sequences of EPO reported for other species. Furthermore, 4 synthetic peptides were designed in 2 distinctive parts of the e...
Carstanjen B, Hoyle NR, Gabriel A, Hars O, Sandersen C, Amory H, Remy B.To evaluate a human assay for quantification of carboxy-terminal cross-linking telopeptide of type I collagen (CTX-I), assess the influence of age on plasma CTX-I concentration, investigate the relationship between plasma CTX-I and serum osteocalcin concentrations, and determine whether concentrations of plasma CTX-I or serum osteocalcin fluctuate in circadian manner in horses. HORSES: 75 clinically normal horses. Methods: Cross-reactivity between equine serum CTX-I and CTX-I antibodies in an automated electrochemiluminescent sandwich antibody assay (ECLIA) was evaluated via a specificity test...
Lee EJ, Raudsepp T, Kata SR, Adelson D, Womack JE, Skow LC, Chowdhary BP.Comparative genomics has served as a backbone for the rapid development of gene maps in domesticated animals. The integration of this approach with radiation hybrid (RH) analysis provides one of the most direct ways to obtain physically ordered comparative maps across evolutionarily diverged species. We herein report the development of a detailed RH and comparative map for horse chromosome 17 (ECA17). With markers distributed at an average interval of every 1.4 Mb, the map is currently the most informative among the equine chromosomes. It comprises 75 markers (56 genes and 19 microsatellites),...
Choi YH, Roasa LM, Love CC, Varner DD, Brinsko SP, Hinrichs K.This study was conducted to evaluate in vivo and in vitro development of in vitro-matured equine oocytes fertilized by intracytoplasmic sperm injection. Oocytes were collected from slaughterhouse-derived ovaries, matured in vitro, and injected with frozen-thawed stallion sperm. In vivo development was assessed after transfer of injected oocytes to the oviducts of recipient mares. Mares were killed 7.5-8.5 days after transfer and the uterus and oviducts flushed for embryo recovery. Of 132 injected oocytes transferred, 69 (52%) were recovered; of these, 25 (36%) were blastocysts with a blastocoe...
De Martin I, Theoret CL.To describe immunolocalization of TGF-beta receptors (RI and RII) in normal equine skin and in thoracic or limb wounds, healing normally or with exuberant granulation tissue (EGT). Methods: Group A: six wounds on one metacarpus and one midthoracic area. Group B: six wounds on both metacarpi, one of which was bandaged to stimulate EGT. Immunohistochemistry was used to detect RI and RII expression in wound margins. Methods: Eight horses, randomly assigned to one of two study groups. Methods: Neutralizing polyclonal anti-rabbit RI and RII antibodies were used to detect spatial expression of RI an...
Karanth S, Pope C.The organophosphorus insecticide tetrachlorvinphos (TCVP) is commonly used as a feed-through larvicide in many livestock species, including cattle and horses. Cholinesterase (ChE) activity in blood (generally plasma or whole blood) is often employed to assess organophosphorus insecticide intoxication in animals as well as humans. In many species, including horse and man, plasma contains predominantly butyrylcholinesterase whereas red blood cells in all species express exclusively acetylcholinesterase. To evalulate the comparative interaction of TCVP with blood ChEs in different species, we com...
Chung C, Leib SR, Fraser DG, Ellis SA, McGuire TC.Improved typing of horse classical MHC class I is required to more accurately define these molecules and to extend the number identified further than current serological assays. Defining classical MHC class I alleleic polymorphism is important in evaluating cytotoxic T lymphocyte (CTL) responses in horses. In this study, horse classical MHC class I genes were analyzed based on reverse transcription (RT)-PCR amplification of sequences encoding the polymorphic peptide binding region and the more conserved alpha 3, transmembrane and cytoplasmic regions followed by cloning and sequencing. Primer s...
Davids BI, Davidson MJ, TenBroeck SH, Colahan PT, Oli MW.To compare the efficacy of sterile preoperative skin antisepsis using either a 5-minute mechanical preparation or 5-minute non-mechanical preparation with chlorhexidine gluconate 4% solution. Methods: Matched design, ANOVA. Methods: Healthy adult Thoroughbred horses (n = 30). Methods: Each horse had both surgical preparation methods randomly assigned to identical sites on the left or right upper thigh. Prepared sites were sampled and cultured for bacteria after each preparation step. Results: Mechanical and non-mechanical preparation techniques significantly reduced bacteria isolated from ...
Koekemoer JJ, Dijk AA.Since protection against African horsesickness (AHS) is serotype-specific, rapid serotyping of AHSV is crucial to identify the correct vaccine serotype for efficient control of the spread of AHS outbreaks, especially when they occur in non-endemic regions. This paper describes the first one-day serotyping procedure that requires only a single RT-PCR and hybridization and which can identify multiple serotypes in mixed infections in one assay. The same region of genome segment 2 of all nine AHSV serotypes is amplified in a single RT-PCR. A universal primer set, designed to amplify the 5'-termina...
Garcia-Duitama J, Chayer B, Garcia D, Goussard Y, Cloutier G.Erythrocyte aggregation is a non-specific marker of acute and chronic inflammation. Although it is usual to evaluate this phenomenon from blood samples analyzed in laboratory instruments, in vivo real-time assessment of aggregation is possible with spectral ultrasound techniques. However, variable blood flow can affect the interpretation of acoustic measures. Therefore, flow standardization is required. Two techniques of flow standardization were evaluated with porcine and equine blood samples in Couette flow. These techniques consisted in either stopping the flow or reducing it. Then, the se...
Ishii H, Leung GN, Yamashita S, Yamada M, Kushiro A, Kasashima Y, Okada J, Kawasaki K, Kijima-Suda I.GW1516 is a peroxisome proliferator-activated receptor-δ agonist in the class of hormones and metabolic modulators. The use of GW1516 is banned in both horseracing and equestrian competitions. To the best of our knowledge, this is the first metabolic study of GW1516 in horses. Methods: After protein precipitation of pre- and post-administration plasma GW1516 samples, the supernatants were analyzed using liquid chromatography/electrospray ionization Q-Exactive high-resolution mass spectrometry to detect GW1516 and its metabolites. Monoisotopic ions of GW1516 and its metabolites were monitored ...
Ioannou A, Lambrou A, Daskalakis V, Pinakoulaki E.The coordination of nitrite in myoglobin (Mb) has been characterized by resonance Raman spectroscopy and the frequencies of the nitrite bound to the heme Fe as well to the 2-vinyl have been computed by density functional theory (DFT) calculations. The DFT Natural Bond Orbital (NBO) analysis and the extensive isotope-labeling in the resonance Raman experiments indicate that NO (O1NO2) is bound to the heme Fe via O1. Based on the vibrational characterization of the reversible transition between low and high spin FeONO/2-nitrovinyl species, we suggest that the key step that triggers the spin-chan...
Hegre OD, Marshall S, Hickey GE.Plasma amine oxidase activities (benzylamine oxidase and spermine oxidase) were determined in the sera of a number of species of various ages. Benzylamine oxidase (BZO) activity, measured spectrophotometrically, was present in bovine, equine, and ovine species examined. Generally its activity in serum increased with the age of the animal. Spermine oxidase activity (SPO) was estimated by a bioassay of in vitro toxicity and did not necessarily correlate with BZO. Cytotoxicity in the presence of spermidine was found only in the sera of the ruminant species examined. Serum activity tended to rise ...
Nishimura M, Nakajima H.Using purified equine infectious anemia (EIA) virus labeled with 3H-glucosamine or 14C-protein hydrolysate, structural proteins were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. As a result, 2 glycoproteins and 10 proteins with molecular weights (mol wt) ranging from 12,000 to 115,000 daltons were demonstrated. Of 12 structural proteins, 3 proteins, namely a glycoprotein with mol wt of 76,000 (gp76) and 2 proteins with mol wt of 25,000 (p25) and 12,000 (p12), respectively, had distinct antigenic activity from one another in immunodiffusion. Development of antibodies a...
Bienzle D, Stanton JB, Embry JM, Bush SE, Mahaffey EA.To compare CBC results obtained by use of an in-house centrifugal analyzer with results of a reference method. Methods: Prospective study. Methods: Blood samples from 147 dogs, 42 cats, and 60 horses admitted to a veterinary teaching hospital and from 24 cows in a commercial dairy herd. Methods: Results obtained with the centrifugal analyzer were compared with results obtained with an electrical-impedance light-scatter hematology analyzer and manual differential cell counting (reference method). Results: The centrifugal analyzer yielded error messages for 50 of 273 (18%) samples. Error message...
de Oliveira LG, Barreto F, Hoff R, Rübensam G, Scherer Kurz MH, Galle G, Gonçalves FF.A method for the determination of five sedatives and 14 β-blocker residues in swine, bovine and equine kidney was validated. Samples were extracted with acetonitrile and purified using dispersive solid phase extraction (d-SPE) with Celite 545 with subsequent analysis by LC-MS/MS. A simplified protocol was applied to validate the method scope extension to include new matrices. Parameters such as recovery, trueness, linearity (r), relative standard deviation (RSD), decision limit (CCα) and method capability (CCβ) were measured for the bovine and equine kidney matrices. The method was applied ...
Araujo-Viel MS, Juliano L, Prado ES.The synthetic tridecapeptide Gly-Leu-Met-Lys-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg was used as a model substrate for horse urinary and porcine pancreatic kallikreins. The Met-Lys bond is hydrolyzed selectively by both enzymes. Oxidation of the methionine residue to sulfoxide made the peptide resistant to both kallikreins. Substitution of either the methionine or lysine residues by norleucine led to peptides in which the Nle-Lys or the Met-Nle bonds, respectively, were susceptible to the urinary kallikrein. The esterolytic and Met-Lys bond-splitting activities of both enzymes were inhibited simil...
Roach J, Schnobrich M, Ellerbrock R, Feijo L, Bradecamp E, Alvarenga MA, Kline K, Canisso I.This study compares two methods for seminal plasma removal by evaluating sperm recovery rates, and motility and morphology of cooled-stored semen. Ejaculates were divided into three groups: control, filtration and cushioned centrifugation. Semen was extended to 25 million sperm/ml using a skim-milk-based extender and stored at 5°C for all groups. Sperm motility (total motility (%TM) and progressive motility (%PM)) was determined at 0, 24, 48 and 72 hours by a computer-assisted sperm analyser. Sperm morphology was assessed using differential interference microscopy. Overall, %TM of the cen...
Ek N.The Pr protein, which is one of the major equine acidic prealbumins and which consists of a large number of phenotypes, has been studied with regard to its chemical identity. Serum samples of known Pr phenotype which had been treated with varying amounts of bovine trypsin were subjected to starch gel electrophoresis at pH 4.8. When a certain amount of trypsin was used, the Pr protein was markedly affected, whereas the other acidic prealbumins retained their normal electrophoreitic pattern. Extracts from three different regions of the acidic prealbumin field were tested by the casein precipitat...
Rudolph W, Remane D, Wissenbach DK, Peters FT.Endophyte fungi (e.g. Epichloë ssp. and Neotyphodium ssp.) in symbiosis with pasture grasses (e.g. Festuca arundinacaea and Lolium perenne) can produce toxic alkaloids, which are suspected to be involved in equine diseases such as fescue toxicosis, ryegrass staggers, and equine fescue oedema. The aim of this study was, therefore, to develop and validate a quantification method for these and related alkaloids: ergocristine, ergocryptine, ergotamine, ergovaline, lolitrem B, lysergic acid, N-acetylloline, N-formylloline, peramine, and paxilline in horse serum. Horse serum samples (1.5mL) were wo...
Walter I.Uterine tubes from cow, sheep, horse, pig, dog, cat, rabbit, and guinea pig were examined immunohistochemically for presence and distribution of contractile cells in the mucosal lamina propria. We tested for the presence of alpha-smooth muscle actin, tropomyosin, desmin, smooth muscle myosin (heavy chain) and cytoskeletal proteins vimentin and cytokeratin. Immunostaining for alpha-smooth muscle actin showed two distribution patterns: either positive cells were freely dispersed in the mucosal lamina propria or a distinct subepithelial layer of positive cells was seen. The first distribution pat...
Kline KH, Bechtel PJ.The purpose of this study was to investigate metabolic changes in equine muscle from birth to 1 yr of age. Duplicate biopsies from the middle portion of the gluteus medius were obtained from a depth of 2 cm beneath the superficial fascia at 1 day, 7 days, 1 mo, 3 mo, 6 mo, and 1 yr of age in 11 quarter horses and at 1 day, 3 mo, 6 mo, and 1 yr of age in 5 Standardbreds. Muscle enzyme activities determined were citrate synthase, 3-hydroxyacyl-CoA dehydrogenase, phosphorylase, and lactate dehydrogenase. Percent fast-twitch, fast-twitch high oxidative, and slow-twitch oxidative fiber types were d...
Mück WM, Henion JD.A screening procedure for the anabolic steroid stanozolol in human and equine urine was developed based on enzymatic hydrolysis, liquid-liquid extraction and reversed-phase liquid chromatography combined on-line with tandem mass spectrometry. The column effluent was introduced into the atmospheric pressure ionization source of a triple-quadrupole mass spectrometer via a heated pneumatic nebulizer liquid chromatograph/mass spectrometer interface. Abundant protonated molecular ions were generated by corona discharge ionization. Confirmation of stanozolol and several of its hydroxylated and dihyd...
Meng Q, Li S, Liu L, Xu J, Liu Y, Zhang Y, Zhang X, Shao Y.Equine Infectious Anemia Virus (EIAV), like other lentiviruses, has a transmembrane glycoprotein with an unusually long cytoplasmic tail (CT). Viral envelope (Env) proteins having CT truncations just downstream the putative membrane-spanning domain (PMSD) are assumed to exist among all wild-type budded virions, and also in some cell-adapted strains. To determine whether CT-truncated Env proteins can cause particularly deleterious effects on the Env expressing cells and/or their neighboring cells, plasmids encoding codon-optimized env gene including full-length (pE863) or CT-truncated (pE686* a...
Go YY, Hazard NW, Balasuriya UBR, Chapman AM, Fitton NS, Kenéz Á, Andrews FM.Accurate quantitative analysis of equine insulin in blood samples is critical for assessing hyperinsulinemia in horses. Although there are various laboratory methods for evaluating equine serum insulin, different immunoassays show significant discrepancies between the determined insulin concentrations and are often not comparable. The aim of this study was to evaluate the Immulite® 1000 chemiluminescent immunoassay (CLIA) to establish independent laboratory and assay-specific cut values to provide an accurate diagnosis of hyperinsulinemia in horses. Thus, the analytical and clinical performan...
Thomas LM, Huntington PJ, Mead LJ, Wingate DL, Rogerson BA, Lew AM.The use of the bacterial expression vector, pGex, to produce an abundant, soluble fusion protein of gp45 from equine infectious anaemia virus is described. Purification of the recombinant protein was achieved by one step affinity chromatography on immobilized glutathione using competitive elution so no harsh conditions were required. This provides a readily available antigen that is defined, plentiful and cheap. Yields of 3.5 mg of purified soluble protein/litre of bacterial culture were obtained. This antigen was found to be suitable for ELISA. Background reactivity to either the glutathione-...
Roig M, Segura J, Ventura R.A method to quantify metabolites of 17beta-nandrolone (17betaN) in boar and horse urine has been optimized and validated. Metabolites excreted in free form were extracted at pH 9.5 with tert-butylmethylether. The aqueous phases were applied to Sep Pak C18 cartridges and conjugated steroids were eluted with methanol. After evaporation to dryness, either enzymatic hydrolysis with beta-glucuronidase from Escherichia coli or solvolysis with a mixture of ethylacetate:methanol:concentrated sulphuric acid were applied to the extract. Deconjugated steroids were then extracted at alkaline pH with tert-...
Giese A, Jude R, Kuiper H, Raudsepp T, Piumi F, Schambony A, Guérin G, Chowdhary BP, Distl O, Töpfer-Petersen E, Leeb T.The cysteine-rich secretory protein (CRISP) family consists of three members called acidic epididymal glycoprotein 1 (AEG1), AEG2, and testis-specific protein 1 (TPX1), which share 16 conserved cysteine residues at their C-termini. The CRISP proteins are primarily expressed in different sections of the male genital tract and are thought to mediate cell-cell interactions of male germ cells with other cells during sperm maturation or during fertilization. Therefore, their genes are of interest as candidate genes for inherited male fertility dysfunctions and as putative quantitative trait loci fo...
Wilson CR, Sauer JM, Carlson GP, Wallin R, Ward MP, Hooser SB.A comparative study of vitamin K(1) 2,3-epoxide reductase (VKOR) activity in vitro was conducted across species. The apparent kinetic constants K(m app), V(max), and Cl(int app) were determined in bovine, canine, equine, human, murine, ovine, porcine, and rat hepatic microsomes. In addition to these enzyme kinetic constants, the IC(50) of warfarin for VKOR was determined in human, murine, porcine, and rat hepatic microsomes. Interspecies differences were observed when comparing the K(m app) (range, 2.41-6.46 microM), V(max) (range, 19.5-85.7 nmol/mg/min), and Cl(int app) (range, 8.2-18.4 ml/mg...
Saad B, Corradin G, Bosshard HR.The antigenic determinants for two monoclonal antibodies directed against horse apo-cytochrome c, a protein of disordered structure, as judged by spectroscopic and hydrodynamic criteria, have been studied by a combination of methods: antigen competition in solution by radio immunoassay and enzyme-linked immunoassay, and differential acetylation of free and antibody-bound antigen. In the latter method the accessibility of lysine residues of the antigen in the antigen-antibody complex is compared to the accessibility in the free antigen. The two antibodies against the heme-free protein do not re...
Kumar S, Kanwar S, Bansal V, Sehgal R.Diphtheria toxin has the capacity to block protein synthesis in cultured mammalian cells, and thus causing cell death. This capacity of diphtheria toxin was utilized for in-vitro neutralization test to determine antibody titer, using Vero cells, which have been found to be susceptible to diphtheria toxin. In the present study, a Vero cell assay was standardized and validated for potency estimation of diphtheria antitoxin serum (DATS). The results obtained by Vero cell assay were compared with in-vivo biological assay. High degree of correlation (+0.98) was found between in-vivo biological assa...
Groot MT, Merkx M, Koper MT.The redox properties of horse and yeast cytochrome c electrostatically immobilized on carboxylic acid-terminated self-assembled monolayers (SAMs) have been determined over a broad pH range (pH 3.5-8) in the absence and presence of nitric oxide. Below pH 6, both proteins exhibit comparable midpoint potentials, coverages, and electron-transfer rate constants, which suggests that they are adsorbed on the SAM in a similar fashion. Above pH 6, a sharp decrease in electron-transfer rate constants is observed for immobilized yeast cytochrome c, which is indicative of a change in the electron tunnelin...
Huang Z, Depoortere I, De Clercq P, Peeters T.Motilin is involved in the regulation of the fasting motility pattern in man and in dog, but may have a different role in other species. Immunoreactive motilin has been demonstrated in several species, but the sequence is mostly unknown. The aim of this study was to isolate and sequence the cDNA encoding the motilin precursor from several mammalian species and from chicken. Total RNA was isolated from the duodenal mucosa of the chicken, dog, cow and horse. In each case single stranded cDNA was synthesized. Motilin cDNA fragments were amplified by PCR, ligated into a plasmid and cloned. Clones ...
Dahm AM, de Bruin A, Linat A, von Tscharner C, Wyder M, Suter MM.We describe the establishment and characterisation of equine keratinocyte cultures with maintenance of a high proliferative capacity up to the second passage. Improved attachment and growth were obtained by seeding primary cells on equine feeder layers. Subcultured keratinocytes showed optimal growth when seeded on collagen type I. The proliferation rate of cells on this substrate exceeded that seen for cells seeded on equine feeder layers. By immunohistochemistry, epithelial origin and state of differentiation of the equine keratinocytes were determined. They expressed keratin and desmoplakin...
Tozaki T, Ohnuma A, Nakamura K, Hano K, Takasu M, Takahashi Y, Tamura N, Sato F, Shimizu K, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Hamilton NA....The creation of genetically modified horses is prohibited in horse racing as it falls under the banner of gene doping. In this study, we developed a test to detect gene editing based on amplicon sequencing using next-generation sequencing (NGS). We designed 1012 amplicons to target 52 genes (481 exons) and 147 single-nucleotide variants (SNVs). NGS analyses showed that 97.7% of the targeted exons were sequenced to sufficient coverage (depth > 50) for calling variants. The targets of artificial editing were defined as homozygous alternative (HomoALT) and compound heterozygous alternative (ALT1/...
Gil MC, Ferrusola CO, Anel-López L, Ortiz-Rodriguez JM, Alvarez M, de Paz P, Anel L, Peña FJ.Spermatozoa undergo apoptotic changes during the cryopreservation process. These changes, recently termed spermptosis, resemble the cryopreservation induced delayed onset of cell death observed after thawing of somatic cells. Due to its importance in cryobiology, methods to easily identify spermptotic cells are warranted. In this study, a well-validated method for identification of spermatozoa with caspase 3 activity was compared with use of the combination of Hoechst 33342 (H-42) and ethidium homodimer (Eth-1). Live, dead and apoptotic spermatozoa assessed with each method were compared using...
Hewetson M, Aaltonen K, Tulamo RM, Sankari S.A simple and accurate method for quantifying sucrose in equine serum that can be applied to sucrose permeability testing in the horse was developed and validated using gas chromatography with flame ionization detection. The assay provided an acceptable degree of linearity, accuracy, and precision at concentrations of sucrose as low as 2.34 μmol/l and as high as 20.45 μmol/l. Percentage recovery of sucrose from serum ranged from 89% to 102%; repeatability and intermediate precision (relative standard deviation) ranged from 3.6% to 6.7% and 4.1% to 9.3%, respectively. The limit of detection wa...