Urine analysis in horses involves the examination of urine to assess the health and physiological status of the animal. This diagnostic tool provides insights into the renal function, hydration status, and potential presence of systemic diseases. Key parameters evaluated in equine urine analysis include pH, specific gravity, protein levels, glucose, ketones, and the presence of blood or sediment. Variations in these parameters can indicate metabolic disorders, infections, or other health issues. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, findings, and clinical implications of urine analysis in equine veterinary practice.
Fidani M, Casagni E, Montana M, Pasello E, Pecoraro C, Gambaro V.Bacteria frequently found in equine urine samples may cause degradation of 17beta-OH steroids. A simple liquid chromatography/tandem mass spectrometry (LC/MS/MS) method has been developed to evaluate the microbiological contamination of equine urine as a marker of poor storage conditions. Norethandrolone was used as the internal standard, and the linearity, sensitivity, precision and accuracy of the method were evaluated. 17beta-OH oxidation was demonstrated for testosterone, nandrolone, trenbolone and boldenone, but did not occur in alpha-epimers such as alpha-boldenone and epitestosterone, d...
Songsermsakul P, Sontag G, Cichna-Markl M, Zentek J, Razzazi-Fazeli E.The paper describes a method for the sensitive and selective determination of zearalenone and its metabolites in urine, plasma and faeces of horses by high performance liquid chromatography and atmospheric pressure chemical ionisation (APCI) mass spectrometry (MS). While only one step sample clean-up by an immunoaffinity column (IAC) was sufficient for plasma samples, urine and faeces samples had to be prepared by a combination of a solid-phase extraction (SPE) and an immunoaffinity column. The method allows the simultaneous determination of zearalenone and all of its metabolites; alpha-zearal...
Hollis AR, Ousey JC, Palmer L, Stoneham SJ, Corley KT.Fenoldopam mesylate, a dopamine-1 receptor agonist, has dose- and species-dependent effects on hemodynamics and renal function. The effects of this drug in normotensive neonatal foals have not been reported. Objective: Two doses of fenoldopam would result in distinct changes in the systemic circulation, urine output, and creatinine clearance of neonatal foals. Methods: Six Thoroughbred foals. Methods: Each foal received 2 dosages of fenoldopam (low dose, 0.04 microg/kg/min; high dose, 0.4 microg/kg/min) and a control administration of saline, in a masked, placebo-controlled study. Results: Hig...
Ho EN, Leung DK, Wan TS, Yu NH.This paper reports two highly efficient liquid chromatography-mass spectrometry (LC-MS) methods for the screening of anabolic steroids, corticosteroids, and acidic drugs for the purpose of doping control in equine sports. Sample extraction was performed using a mixed-mode C8-SCX solid-phase extraction (SPE) cartridge. The first eluted fraction (acidic/neutral fraction) was base-washed and the resulting organic extract was used for the screening of anabolic steroids and corticosteroids by LC-MS using multiple reaction monitoring (MRM) in the positive electrospray ionisation (ESI) mode. The rema...
Maes A, Baert K, Croubels S, De Clercq D, van Loon G, Deprez P, De Backer P.A rapid method for the quantification of amiodarone and desethylamiodarone in animal plasma using high-performance liquid chromatography combined with UV detection (HPLC-UV) is presented. The sample preparation includes a simple deproteinisation step with acetonitrile. In addition, a sensitive method for the quantification of amiodarone and desethylamiodarone in horse plasma and urine using high-performance liquid chromatography combined with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) is described. The sample preparation includes a solid-phase extraction (SPE) with a SCX c...
Stanley SM, Foo HC.A rapid, selective and robust direct-injection LC/hybrid tandem MS method has been developed for simultaneous screening of more than 250 basic drugs in the supernatant of enzyme hydrolysed equine urine. Analytes, trapped using a short HLB extraction column, are refocused and separated on a Sunfire C(18) analytical column using a controlled differential gradient generated by proportional dilution of the first column's eluent with water. Independent data acquisition (IDA) was configured to trigger a sensitive enhanced product ion (EPI) scan when a multiple reaction monitoring (MRM) survey scan s...
Morresey PR, Mackay RJ.To measure serum polymyxin B concentration after single and repeated IV infusions in horses. Methods: 5 healthy horses. Methods: In study 1, 1 mg (6,000 U) of polymyxin B/kg was given IV and blood samples were collected for 24 hours. In study 2, 1 mg of polymyxin B/kg was given IV every 8 hours for 5 treatments and blood samples were collected until 24 hours after the last dose. Polymyxin B concentration was measured as the ability to suppress nitrite production by murine macrophages stimulated with lipopolysaccharide and interferon-alpha. Urine was collected prior to the first drug infusion a...
Marchiondo AA, TerHune TN, Herrick RL.Pyrantel pamoate paste (19.13% w/w pyrantel base) for the treatment of tapeworm, Anoplocephala spp was evaluated for target animal safety and tolerance in horses treated orally at 0, 1, 3, 5, and 10 times the clinical dose of 13.2 mg pyrantel base/kg body weight administered daily for six consecutive days. Parameters evaluated included clinical signs, food and water consumption, body weights, physical examinations, clinical pathology (hematology, coagulation, serum chemistry, urinalyses, and fecal examinations), complete necropsy, organ weights, and histopathology. No adverse events or test ar...
Lampinen-Salomonsson M, Beckman E, Bondesson U, Hedeland M.Altrenogest (17alpha-allyl-17beta-hydroxyestra-4,9,11-trien-3-one) is a steroid used for the control of estrus in horses. This drug can potentially be abused in racehorses as the occurrence of estrus can alter their performance. This work describes an analytical method based on liquid chromatography-tandem mass spectrometry for the detection of altrenogest in horse urine down to a concentration of 13 pg/mL (0.042 nM). Furthermore, the qualitative aspect of metabolism of altrenogest in the horse has been studied. The main transformations that were found for this species were conjugation with gl...
De Clercq D, Baert K, Croubels S, van Loon G, Maes A, Tavernier R, Deprez P, De Backer P.To determine the clinical effects and pharmacokinetics of amiodarone after single doses of 5 mg/kg administered orally or intravenously. Methods: 6 healthy adult horses. Methods: In a cross over study, clinical signs and electrocardiographic variables were monitored and plasma and urine samples were collected. A liquid chromatography-mass spectrometry method was used to determine the percentage of protein binding and to measure plasma and urine concentrations of amiodarone and the active metabolite desethylamiodarone. Results: No adverse clinical signs were observed. After IV administration, m...
Lasne F, Popot MA, Varlet-Marie E, Martin L, Martin JA, Bonnaire Y, Audran M, de Ceaurriz J.A direct detection method for anti-doping control of recombinant human erythropoietin (rHuEPO) abuse in racehorses is proposed. This method involves screening of plasma (or serum) by an enzyme-linked immunosorbent assay specific for human EPO and confirmation in urine samples by characterization of the urinary EPO isoelectric profile. This method was tested on horses that were administered epoetin alpha (rHuEPO) and the hyper-glycosylated form of this drug (darbepoetin alpha).
Dunkel B, Palmer JE, Olson KN, Boston RC, Wilkins PA.Foals may present to a referral hospital with the primary diagnosis of uroperitoneum (UP), or they may develop UP while hospitalized for other reasons. Historical, physical, laboratory, and diagnostic variables of foals presenting with UP were compared to those developing UP while hospitalized. Emphasis was placed on the presence of electrolyte abnormalities, evidence of sepsis or infection, and development of anesthetic complications during surgical correction of the defect. Foals developing UP while in the hospital frequently had a history of dystocia and presented at a very young age (< ...
Buchanan BR, Sommardahl CS, Rohrbach BW, Andrews FM.To determine the effects of a 24-hour infusion of an isotonic electrolyte replacement fluid (IERF) on weight, serum and urine electrolyte concentrations, and other clinicopathologic variables in healthy neonatal foals. Methods: 4 healthy 4-day-old foals. Methods: Prospective study. Methods: An IERF was administered to each foal at an estimated rate of 80 mL/kg/d (36.4 mL/lb/d) for 24 hours. Body weight was measured before and after the infusion period. Urine was collected via catheter during 4-hour periods; blood samples were collected at 4-hour intervals. Variables including urine production;...
Kaneps AJ, Craig AM, Walker KC, True JE.To determine whether iontophoretic administration of dexamethasone to horses results in detectable concentrations in synovial fluid, plasma, and urine. Methods: 6 adult mares. Methods: Iontophoresis was used to administer dexamethasone. Treatments (4 mA for 20 minutes) were administered to a tarsocrural joint of each mare. The drug electrode contained 3 ml of dexamethasone sodium phosphate at a concentration of 4 or 10 mg/ml. Samples of synovial fluid, blood, and urine were obtained before and 0.5, 4, 8, and 24 hours after each treatment. All samples were tested for dexamethasone using an ELIS...
Schott HC, Axiak SM, Woody KA, Eberhart SW.To determine whether the composition of electrolyte pastes formulated for oral administration influences voluntary water intake (WI) by horses recovering from furosemide-induced dehydration. Methods: 6 horses. Methods: Voluntary WI, body weight, and blood and urine constituents were measured before and after induction of dehydration by furosemide administration and overnight withholding of water; these same variables also were measured during a 36-hour rehydration period. Each horse was evaluated 4 times with random application of 4 treatments (electrolyte pastes) that provided 0.5 g of KCl/kg...
Davis JL, Salmon JH, Papich MG.The purpose of this study was to determine the pharmacokinetics and tissue fluid distribution of cephalexin in the adult horse following oral and i.v. administration. Cephalexin hydrate (10 mg/kg) was administered to horses i.v. and plasma samples were collected. Following a washout period, cephalexin (30 mg/kg) was administered intragastrically. Plasma, interstitial fluid (ISF) aqueous humor, and urine samples were collected. All samples were analyzed by high-pressure liquid chromatography (HPLC). Following i.v. administration, cephalexin had a plasma half-life (t(1/2)) of 2.02 h and volume o...
Adams AR, Haines GR, Brown MP, Gronwall R, Merritt K.Pharmacokinetics of difloxacin and its distribution within the body fluids and endometrium of 6 mares were studied after intragastric (IG) administration of 5 individual doses. Difloxacin concentrations were serially measured in serum, urine, peritoneal fluid, synovial fluid, cerebrospinal fluid, and endometrium over 120 h. Bacterial susceptibility to difloxacin was determined for 174 equine pathogens over a 7-month period. Maximum serum concentration (Cmax) was 2.25 +/- 0.70 microg/mL at 3.12 +/- 2.63 h and Cmax after the 5th dose was 2.41 +/- 0.86 microg/mL at 97.86 +/- 1.45 h. The mean elim...
Dumasia MC.The in vivo biotransformation of metoprolol tartrate in the thoroughbred racehorse was studied after administration of a single oral dose. Metoprolol and its basic and bifunctional phase I metabolites were isolated from urine and plasma using mixed mode solid phase extraction (SPE) cartridges. The isolates were derivatised as trimethylsilyl ethers and analysed by capillary column gas chromatography--positive ion electron ionisation and ammonia chemical ionisation mass spectrometry. Metabolism was primarily confined to the oxidative transformations of the p-(2-methoxy)ethyl substituent. Metopro...
Hungerford NL, Sortais B, Smart CG, McKinney AR, Ridley DD, Stenhouse AM, Suann CJ, Munn KJ, Sillence MN, McLeod MD.Due to the potential for misuse of a wide range of anabolic steroids in horse racing, a screening test to detect multiple compounds, via a common class of metabolites, would be a valuable forensic tool. An enzyme-linked immunosorbent assay (ELISA) has been developed to detect 17alpha-alkyl anabolic steroid metabolites in equine urine. 16beta-Hydroxymestanolone (16beta,17beta-dihydroxy-17alpha-methyl-5alpha-androstan-3-one) was synthesised in six steps from commercially available epiandrosterone (3beta-hydroxy-5alpha-androstan-17-one). Polyclonal antibodies were raised in sheep, employing mesta...
Mirza MH, Seahorn TL, Oliver JL, Hosgood G, Moore RM.The objective of the study was to determine whether nitric oxide (NO) is present in clinically healthy horses (control) under basal conditions, and if it increases secondary to naturally acquired strangulating large colon volvulus (affected). Eleven affected horses and 10 controls were studied. Jugular venous blood, abdominal fluid, and urine were collected. The NO concentrations were standardized to the creatinine concentration in the respective samples. A biopsy specimen collected from the large colon pelvic flexure at surgery was divided into subsections for processing for inducible nitric ...
Soma LR, Uboh CE, Guan F, Luo Y, Moate PJ, Boston RC, Driessen B.Hemoglobin-glutamer-200 (HBOC-200) is a hemoglobin (Hb)-based oxygen carrier (HBOC) comprising glutaraldehyde-polymerized bovine Hb. In this study, we sought to determine the pharmacokinetics of this first generation HBOC after IV infusion of 32.5 g of HBOC-200 solution in horses. Quantification of HBOC-200 in equine plasma and urine was performed using a method recently developed by our laboratory. The elimination from plasma was based on size distribution of the bovine Hb polymer. The decline of plasma concentration-time curve of HBOC-200 was described by a noninterchanging 2-compartmental m...
Anderson D, Kollias-Baker C, Colahan P, Keene RO, Lynn RC, Hepler DI.The liposomal cream formulation of diclofenac, an NSAID, is an effective, safe, and convenient way to treat localized areas of inflammation in horses. The results of this study reveal urinary and serum concentrations of diclofenac following topical administration of 1% liposomal diclofenac cream for 10 days at the labeled dose and at 2X and 4X the labeled dose. These results demonstrate the slow absorption and elimination of 1% liposomal diclofenac cream and may be useful when estimating the withdrawal time needed before a competition in order to prevent an inadvertent positive drug test.
Meyer C, Guthrie AJ, Stevens KB.Haematological variables and selected serum indices, particularly those affected by changes in renal and hepatic function, were examined in 6 healthy ponies following 4 intramuscular doses of 4 mg/kg imidocarb dipropionate administered every 72 hours. This treatment regime has been reported to sterilise experimental Babesia equi infections in horses and may have value in preventing the spread of this disease during exportation of possible carrier horses to non-endemic countries. Serum bile acids and serum gamma glutamyltransferase activity were measured to evaluate the effect of this treatment...
Savage KA, Colahan PT, Tebbett IR, Rice BL, Freshwater LL, Jackson CA.To determine the effects of a dose of caffeine (2.5 mg/kg, IV) administered to physically fit Thoroughbreds during incremental exercise testing to fatigue on a treadmill. Methods: 10 conditioned Thoroughbreds. Methods: Horses were randomly assigned to receive caffeine or a control solution. Each horse received both treatments in a crossover design with a 3-week interval between treatments. Each horse was administered caffeine (2.5 mg/kg) or an equivalent amount of a control solution IV. One hour after injection, each horse performed an incremental exercise test to exhaustion. Hematologic value...
Yu NH, Ho EN, Leung DK, Wan TS.Anabolic steroids have the capability of improving athletic performance and are banned substances in the Olympic games as well as in horseracing and equestrian competitions. The control of their abuse in racehorses is traditionally performed by detecting the presence of anabolic steroids and/or their metabolite(s) in urine samples using gas chromatography-mass spectrometry (GC-MS). However, this approach usually requires tedious sample processing and chemical derivatisation steps and could be very insensitive in detecting certain steroids. This paper describes a high performance liquid chromat...
McKinney AR, Suann CJ, Stenhouse AM.A method has been developed for the detection of modafinil and its major metabolite, modafinil acid, in equine urine by solid-phase extraction and positive ion electrospray ionisation liquid chromatography/mass spectrometry. The method has been applied to the analysis of equine urine samples obtained after the oral administration of modafinil. Modafinil acid was the major component in the urine, and was detected up to 4 days post-administration. Unchanged modafinil was present at substantially lower concentrations, and was detected for only 24 hours.
Kohn RA, Dinneen MM, Russek-Cohen E.The objectives of this study were to evaluate the potential for using blood urea N concentration to predict urinary N excretion rate, and to develop a mathematical model to estimate important variables of N utilization for several different species of farm animals and for rats. Treatment means (n = 251) from 41 research publications were used to develop mathematical relationships. There was a strong linear relationship between blood urea N concentration (mg/100 mL) and rate of N excretion (g x d(-1) x kg BW(-1)) for all animal species investigated. The N clearance rate of the kidney (L of bloo...
Toutain PL, Reymond N, Laroute V, Garcia P, Popot MA, Bonnaire Y, Hirsch A, Narbe R.To determine pharmacokinetic parameters for meloxicam, a nonsteroidal anti-inflammatory drug, in horses. Methods: 8 healthy horses. Methods: In the first phase of the study, horses were administered meloxicam once in accordance with a 2 x 2 crossover design (IV or PO drug administration; horses fed or not fed). The second phase used a multiple-dose regimen (daily oral administration of meloxicam for 14 days), with meloxicam administered at the recommended dosage (0.6 mg/kg). Plasma and urine concentrations of meloxicam were measured by use of validated methods with a limit of quantification of...
Pu F, McKinney AR, Stenhouse AM, Suann CJ, McLeod MD.A study of the equine phase II metabolism of the anabolic agent boldenone is reported. Boldenone sulfate, boldenone glucuronide and their C17-epimers were synthesised as reference standards in our lab and a method was developed for their detection in a horse urine matrix. Solid phase extraction was used to purify the analytes, which were then detected by ion trap LC/MS. Negative and positive ionisation mode MS(2) were used for the detection of sulfate and glucuronide conjugates, respectively. Boldenone sulfate and 17-epiboldenone glucuronide were detected as the major and minor phase II metabo...
Roberts MC, Seawright AA, Ng JC, Norman PD.Chronic mercuric chloride intoxication in an aged horse given 0.8 mg Hg/kg/day for 14 weeks was manifest by signs of progressive respiratory difficulty and renal disease. The effects were not self-limiting after mercury was withdrawn, and the animal was destroyed six weeks later. Renal function changes included heavy glycosuria, modest proteinuria, phosphaturia, reduced urine osmolality, gradually increasing urine production, reduced glomerular filtration rate, and terminally, azotemia. The condition bore similarities to the Fanconi syndrome in man. Urinary gamma-glutamyl transpeptidase, alkal...
Lasne F, Popot MA, Varlet-Marie E, Martin L, Martin JA, Bonnaire Y, Audran M, de Ceaurriz J.A direct detection method for anti-doping control of recombinant human erythropoietin (rHuEPO) abuse in racehorses is proposed. This method involves screening of plasma (or serum) by an enzyme-linked immunosorbent assay specific for human EPO and confirmation in urine samples by characterization of the urinary EPO isoelectric profile. This method was tested on horses that were administered epoetin alpha (rHuEPO) and the hyper-glycosylated form of this drug (darbepoetin alpha).
Brown MP, Stover SM, Kelly RH, Farver TB.Six healthy adult mares were given a single dose of kanamycin sulfate (200 mg/ml) IM at a dosage rate of 5 mg/kg of body weight. Kanamycin concentrations in serum, synovial fluid, peritoneal fluid, and urine were measured serially over a 48-hour period. The mean peak serum kanamycin concentration was 12.55 microgram/ml at 1 hour. Mean peak kanamycin concentrations in synovial fluid and peritoneal fluid were 7.25 microgram/ml and 9.27 microgram/ml at 2 hours and 3 hours, respectively. These concentrations decreased steadily in parallel with serum concentrations and were still measurable at 48 h...
Lindsay FE, Burton FL.Although "urine testing" is said to enable the male equid to assess the sexual status of the mare, there are no reports in the literature of any detailed study of this behavioural response of the stallion. Behavioural response to conspecific urine was studied in two horse stallions and one donkey stallion. The relevant nasopalatine anatomy is described. Events observed during urine testing included head, neck, lip, jaw, tongue movements, penile changes and nasal secretion. Nasal endoscopy indicated that the source of part of the nasal secretion was the secretory glands of the vomeronasal organ...
Hollis AR, Ousey JC, Palmer L, Stephen JO, Stoneham SJ, Boston RC, Corley KT.Norepinephrine increases arterial blood pressure but may have adverse effects on renal blood flow. Fenoldopam, a dopamine-1 receptor agonist, increases urine output in normotensive foals. The combination of norepinephrine and fenoldopam may lead to improved renal perfusion compared with an infusion of norepinephrine alone. The combined effects of these drugs have not been reported in the horse. Objective: Norepinephrine will alter the hemodynamic profile of foals without affecting renal function. Addition of fenoldopam will change the renal profile during the infusions without changing the hem...
Wynne PM, Vine JH, Amiet RG.The influence of sampling variables on the concentration of the dopamine metabolites 3-methoxytyramine (3MT), dihydroxyphenylacetic acid (DOPAC) and homovanilic acid (HVA) was examined in equine urine. A logarithmic transformation of the data for all horses gave distribution which approximated the normal distributions for each metabolite. The mean urinary concentration of 3 MT in horses was 214 ng/mL and the application of a threshold with a probability of 1 in 10,000 gave an actionable level of 4 microg/mL. Environmental variables were not forensically significant in determining the populatio...
Wynne PM, Vine JH, Amiet RG.Protopine was extracted from Fumaria officinalis and purified by column chromatography. Urine samples were collected from horses and a human volunteer that had been administered either F. officinalis or protopine free base. Plant and urine samples were acetylated and analysed by GCMS after solid-phase extraction (SPE). The urinary metabolites of protopine were identified as 4,6,7,13-tetrahydro-9,10-dihydroxy-5-methyl-benzo[e]-l,3-benzodioxolo [4,5-1][2] benzazecin-12(5H)-one, 4,6,7,13-tetrahydro-10-hydroxy-9-methoxy-5-methyl-benzo[e]-1,3-benzodioxolo[4,5-1][2] benzazecin-12(5H)-one and 4,6,7,1...
Sams R, Pizzo P.The possibility exists that ketamine, or ketamine in combination with xylazine, is being used illicitly to affect the performance of racehorses. This study was undertaken to identify the metabolites of ketamine in the urine of adult horses and to evaluate methods for detecting and confirming ketamine administration. Detection of ketamine and two ketamine metabolites is described using thin-layer chromatography (TLC) and their identities are confirmed by comparing their mass spectra and gas chromatographic retention times with those of authentic standards.
Robb EJ, Kronfeld DS.A 3-year-old mare repeatedly had clinical signs of rhabdomyolysis on mild exertion. Serum creatine kinase and aspartate transaminase activities were high at rest. Responses to dietary sodium bicarbonate were tested through 7 alternating periods of supplementation of a basal ration of timothy hay and oats. Physical signs; venous blood pH and gases; blood glucose and lactate; serum electrolytes, enzymes, and creatinine; and urine pH were monitored before and after exercise. Dietary sodium bicarbonate raised resting venous blood pH and bicarbonate slightly and significantly increased urine pH fro...
Jaussaud P, Guieu D, Courtot D, Barbier B, Bonnaire Y.A tolfenamic acid metabolite, a hydroxylated product, has been identified in equine plasma and urine samples using gas chromatography-mass spectrometry in the electron-impact and chemical-ionization modes. The method also allows the qualitative monitoring of the elimination of the drug and its metabolites from plasma. The two compounds are detected up to 48 and 24 h, respectively, after a single oral administration of a 30 mg/kg dose. The simultaneous detection of the two products increases the reliability of anti-doping control analysis.
Wong ASY, Leung GNW, Leung DKK, Wan TSM.Anabolic steroids are banned substances in equine sports. Gas chromatography-mass spectrometry (GC-MS) has been the traditional technique for doping control analysis of anabolic steroids in biological samples. Although liquid chromatography-mass spectrometry (LC/MS) has become an important technique in doping control, the detection of saturated hydroxysteroids by LC-MS remains a problem due to their low ionization efficiency under electrospray. The recent development in fast-scanning gas-chromatography-triple-quadrupole mass spectrometry (GC-MS/MS) has provided a better alternative with a sign...
Alexander F.1. The effect on plasma, urinary and faecal electrolytes of frusemide and hydrochlorthiazide was measured in ponies, mean weight 180 kg. 2. The rapid loss in urine of large quantities of sodium had only a small effect on plasma sodium concentration. 3. Faecal sodium excretion was increased substantially after the administration of frusemide. 4. Frusemide increased faecal potassium during the 48 h following administration and faecal water in the 24/48 h period. It also produced a hypopotassaemia. 5. Hydrochlorthiazide increased faecal chloride during the 24 h after administration. 6. Frusemide ...
Sterk S, Herbold H, Blokland M, van Rossum H, van Ginkel L, Stephany R.For a number of species it is known that nortestosterone, either the alpha- or beta-epimer, can be of endogenous origin. For goats and mares similar results have not yet been published. As a follow-up on the experiments with cattle, a large number of urine samples per animal were collected from pregnant goats, sheep and mares. These samples were analysed for the presence of alpha- and beta-nortestosterone and alpha-estradiol using GC-MS. The results show that in the goats and mares studied alpha-nortestosterone is present during pregnancy. In this study no alpha-nortestosterone could be demons...
Göktaş EF, Kabil E, Arıöz F.Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used in therapeutic doses in human and veterinary medicine for the treatment of inflammation, pain, and fever. A method for the simultaneous determination of nine NSAIDs, known as therapeutic prohibited substances, in equine urine was developed and fully validated according to the European Commission Decision 2002/657/EC and Association of Official Racing Chemists criteria. The validation was performed for naproxen, flunixin, ketoprofen, diclofenac, eltenac, meclofenamic acid, phenylbutazone, vedaprofen, and carprofen in equine urine i...
Chen JW, Uboh CE, Soma LR, Li X, Guan F, You Y.To evaluate whether urine supernatant contains amplifiable DNA and to determine factors that influence genotyping of samples from racehorses after storage and transportation. Methods: 580 urine, 279 whole blood, and 40 plasma samples obtained from 261 Thoroughbreds and Standardbreds. Methods: Genomic DNA was isolated from stored blood and urine samples collected from racehorses after competition. Quantified DNA was evaluated to determine whether 5 equine microsatellite loci (VHL20, HTG4, AHT4, HMS6, and HMS7) could be amplified by use of PCR techniques. Fragment size of each amplified locus wa...
Stucki M, Voegel CD, Binz TM, Kraemer T, Lavaud A, Voelter K.Equine sport agencies list steroids as prohibited substances for competing horses. Objective: The objective of this study was to investigate if the controlled substances dexamethasone and prednisolone are detectable in equine serum and urine samples during and after treatment with eye drops and if this can generate a positive doping test. Methods: Prospective cohort study. Methods: The study cohort included 11 horses. One eye of the horses was treated with either dexamethasone (Maxitrol 0.1%, n = 5 eyes) or prednisolone (Pred forte 1%, n = 6 eyes) eye drops 3 times daily for 14 days. Dexa...
Delbeke FT, Debackere M.A high pressure liquid chromatographic (HPLC) method for measuring the theobromine content in cocoa husks, pelleted food and horse urine is described. Starting with 2 ml of urine, concentrations of 500 ng/ml could easily be detected. When feed containing 38.4 mg of theobromine was given twice daily to horses for 2 1/2 days, two days were needed after the last intake before the theobromine concentrations fell below the threshold value of 2 micrograms/ml. The time at which the peak excretion rate occurred varied from 2 to 12 h after the last administration, while the excretion rate seemed to be ...
Stanley S, Van den Berg K, Foo HC, Deng D.The metabolism of the masking agent tolcapone in the horse has been investigated. This substance was found to have undergone various chemical transformations that produced a large variety of phase I metabolites, as well as glucuronide and sulfate conjugation. Confirmation of the presence of tolcapone and the 3-O-methylated metabolite in the blood samples collected up to 240 minutes and in urine obtained up to 24 hours, was successfully conducted using both gas chromatography- and liquid chromatography-tandem mass spectrometry techniques. The 3-O-methyl tolcapone is the better marker to use i...