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.
Luther DG, Cox HU, Dimopoullos GT.Fatty acid composition of erythrocytes of healthy horses was determined. Three fatty acids (C16:0, C18:0, and C18:1) were found in approximately equal quantities and comprised 72.17% of the total. Nine other fatty acids were found in small amounts. Saturated fatty acids constituted 67.2% of the total. Marked variation was demonstrated in the occurrence and distribution of fatty acids in the sterol ester, triglyceride, phospholipid, and free fatty acid fractions.
Parodi PW.Milk triglycerides from the echidna, koala, Tammar wallaby, guinea pig, dog, cat, Weddell seal, horse, pig and cow were subjected to fatty acid and stereospecific analysis to determine the positional distribution of the fatty acids in the triglycerides. The samples presented a wide range of fatty acids, most of which varied in content among species. The compositions of the acids at the 3 positions also varied among species, reflecting the content of these acids in the triglycerides. However, there was a general similarity in fatty acid positional distribution patterns for all the species with ...
Arriola J, Foote RH.Because microfloral content of stallion semen tends to be high, and strains may be resistant to commonly used antibiotics, amikacin was tested with stallion semen and compared with bull semen. Nine ejaculates to stallion semen were incubated at 37 C in egg yolk-tris extender for 0, 2, 4, 6, 8 and 10 h in the presence of amikacin concentrations of 0, 50, 100, 250, 500, 1,000 and 10,000 microgram/ml, with penicillin and penicillin-streptomycin as controls. Averaged over all incubations, spermatozoal motility was 44, 48, 49, 46, 45, 45 and 19%, for increasing concentrations of amikacin, compared ...
Cross AR, Higson FK, Jones OT, Harper AM, Segal AW.1. The absorption coefficient of human neutrophil plasma-membrane reduced-minus-oxidized cytochrome b-245 was determined [delta epsilon (mM; 559-540 nm) = 21.6 cm-1]. 2. Neutrophil polymorphonuclear leucocytes (neutrophils) were prepared from human, ox, horse and pig blood. In each case plasma-membrane fractions were found to contain low-potential cytochrome b. When membranes from horse neutrophils were incubated anaerobically with either NADH or NADPH the cytochrome b became reduced. Prior stimulation of the cells with phorbol myristate acetate did not increase the rate or extent of cytochrom...
Lanneau M, Loir M.Using standardized methods for protein extraction and analysis, the testes of rams, bulls, goats, boars, stallions, rats, cats, hedgehogs, European mink and ferrets were examined for basic spermatid nucleoproteins by electrophoresis. The results suggest that differences exist in the total number of these proteins as well as in the number and amount of the cross-linked cystein-containing proteins. These differences appear to be more family-specific than species-specific.
Sahu SP, Wool S, Breese SS.In uterine or cervical specimens obtained from pony mares infected with streptomycin-resistant contagious equine metritis bacteria, several colonies of the bacteria which differed in morphologic characteristics were recognized during their primary isolation on Eugon chocolate agar and tryptose chocolate agar plates. The differences were usually not observed until plates were incubated 10 to 15 days. On Eugon chocolate agar plates, smooth colony, sandy colony with rings, and colony with blebs were recognized. On tryptose chocolate agar plates, only a round smooth convex colony was observed. By ...
Peters GJ, Veerkamp JH.Optimal conditions for stimulation by phytohaemagglutinin (PHA) were established for equine, porcine, ovine and human lymphocytes in MEMS medium. Optimal thymidine concentration was determined for assay of cell transformation. With all species tested horse serum gave highest thymidine incorporation. Homologous serum was not more appropriate for lymphocytes of man, pig and sheep. Optimal stimulation was achieved at 20, 0.5-5, 5, and 10-40 micrograms PHA per 10(6) cells for human, equine, porcine and ovine lymphocytes, respectively.
Keay G, Doxey DL.Samples of serum from both young and adult normal cattle, sheep and horses were subjected to protein electrophoresis on agarose gel films. After processing, the stained electrophoretic patterns and densitometric traces of each species exhibited certain specific characteristics. The separations also revealed differences between young and adult animals of the same species. These age-related differences are described here.
Cheevers WP, Roberson SM, Brassfield AL, Davis WC, Crawford TB.A virus with the morphologic and biochemical properties of the family Retroviridae has been isolated from cultured cells explanted from a malignant tumor induced by intradermal inoculation of equine sarcoid cells into a combined immunodeficient Arabian foal. By electron microscopy, intracytoplasmic, extracellular, and budding particles measuring 89 to 120 nm with electron-lucent cores were seen. Virus purified from the medium of cultured cells had a buoyant density of 1.15 g/cm3 in isopycnic sucrose-gradient centrifugation, incorporated radiolabeled uridine but not thymidine, and had constitut...
Martin DH, Dietz WH, Alvaerez O, Johnson KM.One hundred and fifty-eight strains of Venezuelan equine encephalomyelitis virus were typed antigenically and classified epidemiologically as either epizootic or enzootic. Plaque sizes for 148 of these strains were determined, and the pH requirements for hemagglutination (HA) of goose erythrocytes of 131 were studied. Only antigenic variant group IABC strains could be classified epidemiologically as epizootic. In vitro these strains were characterized by the formation of small plaques in Vero cells and a relatively narrow pH range for optimum HA reactivity. Experimental studies in horses confi...
Bártek J, Viklický V, Franĕk F, Angelisová P, Dráber P, Jarosíková T, Nĕmec M, Verlová H.Five stable hybridoma lines were prepared using the myeloma cell line P3-X63-Ag.653 and spleen cells of mice hyperimmunized by pig transferrin. All hybridomas grew well in mouse peritoneal cavity and produced antibodies of the IgG1 subclass. Antibody preparations obtained from ascitic fluids tested for their capacity of antigen precipitation. No precipitation was obtained with single antibodies and with pairs of antibodies. Three out of 10 possible triads gave clear and sharp precipitation zones and rings in immunodiffusion tests performed in agar gel. All 5 antibodies were shown by quantitati...
Lindmark DG, Jarroll EL, Timoney PJ, Shin SJ.The energy metabolism of the English E-CMO strain of contagious equine metritis bacterium was studied in whole cells and cell extracts. This bacterium appears to have an active Krebs cycle and probably obtains energy by oxidative phosphorylation since glycolysis and the hexose monophosphate pathways appear to be absent. These conclusions are based on the findings that [U-14C]glucose incorporation by this bacterium is below the level of detection, and that respiration is stimulated by Krebs cycle intermediates (i.e., malate, citrate, and succinate), but not by glucose, fructose, maltose, or suc...
Jagodzinski PW, Funk GF, Peticolas WL.The nature of the binding of aromatic aldehyde and aromatic alcohol substrates to the catalytic zinc of equine liver alcohol dehydrogenase has been studied by using resonance-enhanced Raman spectroscopy. When an excess of both enzyme and coenzyme to substrate is used, a stable ternary chemical intermediate is formed between liver alcohol dehydrogenase and the reduced coenzyme, nicotinamide adenine dinucleotide, and the aldehyde, p-(dimethylamino)benzaldehyde, in the pH range 8.5-0.6. Resonance-enhanced Raman spectra clearly show that this same intermediate is formed between the excess enzyme, ...
Naef A, Damerau B, Keller HU.The relationship between the short transient intracellular increase in cAMP levels on the one hand and chemotaxis or crawling movements on the other hand was investigated using human and equine granulocytes. C5ades arg, f-met-leu-phe, human serum albumin and immunoglobulin were used as stimulating agents. There was no strict correlation between the induction of crawling movements or of chemokinesis in general and the generation of the cAMP peak. But there was so far a strict parallelism between the occurrence of the chemotactic response and the cAMP peak. However, the magnitude of the peak was...
Brems DN, Liu YC, Stellwagen E.The heme iron of horse heart cytochrome c was selectively removed using anhydrous HF. The product, porphyrin c, exhibits the viscosity, far ultraviolet circular dichroic, and fluorescence properties characteristic for native cytochrome c. However, porphyrin c is more susceptible to denaturation by guanidine hydrochloride and by heat than is the parent cytochrome. All of the conformational parameters of porphyrin c exhibit a common reversible transition centered at 0.95 m guanidine hydrochloride at 23 degrees C and pH 7.0. Guanidine denatured porphyrin c refolds in two kinetic phases having tim...
Pierrot M, Astier JP, Astier M, Charles M, Drenth J.A detailed study of the crystallization of hog and horse colipases has been undertaken. Several crystallographic varieties have been obtained and a 0.3-nm resolution structure determination is actually in progress. The sequence of the A form of horse colipase (one methionine) is given. From spectrophotometric experiments and sequence comparisons, the involvement of the aromatic residue in position 52 in the micelle binding site has been demonstrated.
Zinkl JG, Brown PD.Horse polymorphonuclear leukocytes (PMN) isolated from horse blood by sedimentation and isotonic lysis and having about 25% accompanying lymphocytes were as effective at chemotaxis as nearly pure PMN isolated by density gradient techniques. N-Formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP), used as a representative of the formylmethionyl peptides (produced by prokaryocytic organisms), was effective as a chemoattractant only at the high concentration of 10(-4) M. When serum was preincubated with FMLP at concentrations as low as 10(-8) M, the serum attracted horse PMN. This activity was not g...
Visser S, Jenness R, Mullin RJ.Three groups of casein components were isolated from horse milk. Group I is almost insoluble at acid and neutral pH, and is rather heterogeneous on alkaline gels with or without sodium dodecyl sulphate. Group II shows strong similarity to beta-casein from other species, as concluded from its amino acid composition and its N- and C-terminal sequences. This group consists of five electrophoretically distinguishable forms, all containing ester phosphate groups but no carbohydrate. Group III is composed of C-terminal fragments of the beta-like (group II) fraction and probably arises from the actio...
Caple IW, Doake PA, Ellis PG.Studied were made to determine if a practical assessment of the calcium and phosphorus nutrition of horses could be obtained from an analysis of urine samples. The concentrations of Ca and P in urine samples changed markedly when groups of 4 mares were fed diets containing from 1.0 to 3.9 g Ca/kg and from 1.5 to 6.1 g P/kg, but serum concentrations of Ca and P remained relatively constant. The concentrations in single urine samples were considered unreliable indicators of excretion of the minerals because of variations in water excretion, and two methods to overcome this problem were examined....
Yamagishi H, Nagamine T, Shimoda K, Ide S, Igarashi Y, Yoshioka I, Matumoto M.Single radial hemolysis (SRH), neutralization (NT), and hemagglutination inhibition (HI) tests were carried out on sera from horses immunized against the Prague and Miami strains of equine influenza virus. The HI and NT tests demonstrated good sensitivity; the sensitivity of the SRH test was somewhat lower. The NT titers of individual sera were correlated very closely with the HI titers, although the NT titers were higher. SRH zone diameters of individual sera also showed significant correlation with the NT and NI titers. The SRH test appears to be suitable for large-scale serological surveys ...
Houghton E.The methylated xanthines caffeine and/or theobromine are commonly encountered in drug-positive samples from racehorses and their metabolism and excretion in the horse and their analysis in urinary extracts has been of particular interest in this laboratory. Due to their polar nature the dimethylxanthines theobromine, theophylline and paraxanthine give unsatisfactory gas chromatographic performance and require derivatization prior to analysis by gas chromatography mass spectrometry. The present paper describes a simple deuteromethylation procedure to render the compounds amenable to analysis by...
Roberts BL, Blake JW, Tobin T.Horses pretreated with 6.6 mg/kg of phenylbutazone were injected with 1 mg/kg of furosemide intravenously. Furosemide had no clinically significant effect on either plasma levels or plasma half-life of phenylbutazone. Furosemide reduced urinary levels of phenylbutazone 18-fold to concentrations which may result in inconsistent drug detection in routine screening tests. The results show that it is not possible to monitor compliance with phenylbutazone medication rules by means of urinalysis alone if the use of furosemide is permitted. Furosemide treatment, however, does not interfere with monit...
Demir C, Brereton RG, Dumasia MC.After oral administration of quinine sulfate to a thoroughbred mare, seven urine samples were obtained over a 45.5 h period. Using gas chromatography -electron impact ionization and positive-ion chemical ionization mass spectrometry, quinine and five putative metabolites were detected and tentatively identified in enzyme-hydrolysed post-administration urine; all metabolites involved some form of oxidation. The parent drug could be detected for about 16 h and some phase I biotransformation products for up to 40 h post-administration.
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.
Otto P, Elschner M, Schulze P, Prudlo J, Schrader R.The commercially available immunoassay "OnSite Rotavirus" was used for the detection of animal rotaviruses in 113 faecal samples. The sensitivity of the test was 88% and the specificity 96% compared with reference methods (EIA, EM). This test would detect approximately 4.4 x 10(6) to 1.8 x 10(7) virus particles per ml. The presence of virus could be demonstrated in fresh faecal samples from cattle, horses and pigs within a few minutes. The rotaviruses of group A were identified independently of the virus serotype. Further results and additional problems of using this test kit are described.
Nunez R, Gomes-Keller MA, Schwarzwald C, Feige K.RATIONALE: Thrombocytopenia is a platelet associated process that occurs in human and animals as result of i) decreased production; ii) increased utilization; iii) increased destruction coupled to the presence of antibodies, within a process know as immune-mediated thrombocytopenia (IMT); or iv) platelet sequestration. Thus, the differentiation of the origin of IMT and the development of reliable diagnostic approaches and methodologies are important in the clarification of IMT pathogenesis. Therefore, there is a growing need in the field for easy to perform assays for assessing platelet morpho...
Staszyk C, Gasse H.In order to display the collagen-fiber arrangement in the equine periodontal ligament an inexpensive and easy staining procedure with fluorescein was applied to paraffin sections. After fluorescein labeling a section was suitable for successful examination with three special microscopical systems: a) fluorescence microscopy b) phase contrast microscopy and c) polarized light microscopy. Collagen fibers were clearly displayed as compact structures in the fluorescence microscope. This distinct feature of the fluorescent image generated an almost three-dimensional impression of the fiber arrangem...
Karlström K, Essén-Gustavsson B.An assumed link between red cell hypervolaemia, an excessive amount of training and impaired performance of hypervolaemic horses has led to a theory that the muscle fibres could be affected. Myosin heavy chain (MHC)-based fibre type composition in gluteus medius muscle of red blood cell normo- (NV) and hypervolaemic (HV) Standardbred trotters was evaluated using immunohistochemistry. Muscle biopsies were obtained from 13 NV and 16 HV horses. Serial transverse sections were cut and reacted with antibodies against different isoforms of the myosin heavy chains MHCI, MHCIIA and MHCIIX. Sections we...
Honoré ML, Pihl TH, Busk-Anderson TM, Flintrup LL, Nielsen LN.D-dimer has value as a marker of thrombosis in critically ill horses and can provide additional information about prognosis. However, there are currently no equine species-specific d-dimer assays available, nor has there been any formal investigation of the applicability of human d-dimer assays in horses, so it is unknown, which assay performs best in this species. The aim of this study was therefore to evaluate and compare two human d-dimer assays for their applicability in horses. The study included four groups of horses: clinically healthy horses, horses with gastrointestinal (GI) disease a...
Martín-Cuervo M, Aguirre CN, Gracia LA, Barrera R, Ezquerra LJ, Martinez-Subiela S, Cerón JJ.Point-of-care (POC) systems for the joint measurement of Troponin and D-dimers have not been studied in horses. The aim of this study was to perform the validation of a POC system (AQT90 FLEX) for the measurement of cardiac troponin I (cTnI) and D-dimers in the serum of horses with gastrointestinal diseases. The main objective was to evaluate whether or not this system can distinguish healthy animals from diseased animals. A sample of 33 horses was included in the study: control group (n = 10) and horses with gastrointestinal disorders (n = 21), which were classified according to their outco...
Kharakhonycheva NV, Likhtenshteĭn GI, Shkileva EA, Adamenkova MD.The possible use of EPR spectroscopy (spin labelling) for the study of horse liver alcohol dehydrogenase with a silochrome adsorbent is discussed. The rotatory diffusion of nitroxyl labels chemically linked to the enzyme was studied with reference to the time of the enzyme incubation with the adsorbent and the degree of its accumulation on the adsorbent surface. The mobility of nitroxyl radicals attached to the protein globules was shown to increase with time. It was concluded that the conformation of the enzyme molecules changes during their interaction with the adsorbent.
Park J, Shin YO, Choo HY.The propionylpromazine concentrations in plasma after intramuscular administration to horses were determined using gas chromatography with nitrogen-phosphorus detection. After hydrolysis by beta-glucuronidase/arylsulphatase, the parent drug and three metabolites were detected in urine. The metabolites were identified as 2-(1-hydroxypropyl)promazine, 2-(1-propenyl)promazine and 7-hydroxypropionylpromazine by gas chromatography-mass spectrometry. No N-demethylated or sulphoxidated metabolites of propionylpromazine were observed in the horse urine.
Gunther JD, Foley CW, Gaverick HA, Plotka ED.Progesterone concentrations were measured in milk and blood plasma for 15 mares throughout a normal estrous cycle and early pregnancy to determine the feasibility of utilizing progesterone in milk as an indicator of pregnancy. Samples were obtained daily from foaling until diagnosis of pregnancy by rectal examination at 30 to 35 days of gestation. Progesterone in milk and blood plasma was quantified by radioimmunoassay. Mean progesterone concentrations (+/- SE) in plasma from foaling to foal heat and during estrus, luteal phase and pregnancy were .51 +/- .09 ng/ml, .53 +/- .08 ng/ml, 3.88 +/- ...
Borin G, Filippi B, Cavaggion F, Marchiori F.A solution synthesis is described of the partially protected N alpha-benzyloxycarbonylheptadecapeptide Z-Lys (Tfa)-Thr-Glu-Arg-Glu-Asp-Leu-Ile-Ala-Tyr-Leu-Lys (Tfa)-Lys (Tfa)-Ala-Thr-Asn-Glu (OBu t)-OBu t corresponding to sequence 88-104 of horse heart cytochrome c. The synthesis is achieved through the preparation of two subunits H1 (sequence 88-96) and H2 (sequence 97-104) and their linkage by an azide coupling step.