The topic of drugs and horses encompasses the study of various pharmacological agents used in equine medicine for therapeutic purposes. This includes the administration of medications for pain management, disease treatment, and performance enhancement. The pharmacokinetics and pharmacodynamics of drugs in horses are key areas of research, as they determine the absorption, distribution, metabolism, and excretion of these substances. Additionally, the topic covers the detection and regulation of substances in competitive equestrian sports to ensure fair play and animal welfare. This page compiles peer-reviewed research studies and scholarly articles that explore the effects, safety, and regulatory aspects of drug use in equine health and performance.
Larsen EA, Lack AC, Wassack E.The use of poloxamer 407 gels have been reported in several studies to prolong the release of drugs at the injection site. Oral lesions unrelated to dental disease are rare but may result in ulceration and sequestration of bone. To date, there have been no reports on the use of penicillin G potassium poloxamer 407 gel and its effect on wound healing. The present case report describes the use of a penicillin G potassium poloxamer 407 gel for the treatment of a sublingual abscess involving the mandible in a 20 year old Arabian mare who initially presented with acute onset of dysphagia, hypersali...
Gupta S, Vohra S, Sethi K, Gupta S, Bera BC, Kumar S, Kumar R.High cytotoxicity and increasing resistance reports of existing chemotherapeutic agents against T. evansi have raised the demand for novel, potent, and high therapeutic index molecules for the treatment of surra in animals. In this regard, repurposing approach of drug discovery has provided an opportunity to explore the therapeutic potential of existing drugs against new organism. With this objective, the macrocyclic lactone representative, ivermectin, has been investigated for the efficacy against T. evansi in the axenic culture medium. To elucidate the potential target of ivermectin in T. ev...
Gupta S, Vohra S, Sethi K, Gupta S, Kumar S, Kumar R.The kinetoplastid protozoan parasite, Trypanosoma evansi causes a fatal disease condition known as Surra in equines throughout the globe. Disease condition being acute in nature, entrust a huge economic and health impact on the equine industry. Till date, quinapyramine methyl sulphate (QPS) is the first line of treatment and a panacea for the T. evansi infection in equines. Still after the >70 years of its discovery, there is no clue about the mode of action of QPS in T. evansi. The establishment of in vitro cultivation of T. evansi in HMI-9 media has provided opportunity to study the alte...
Rabbogliatti V, Amari M, Brioschi FA, Di Cesare F, Zani DD, De Zani D, Di Giancamillo M, Cagnardi P, Ravasio G.A balanced anaesthetic protocol is a common concept in modern veterinary anaesthesia and aims to maintain good intraoperative cardiopulmonary function. In horses, alpha-2-agonists produce sedation and analgesia and have been shown to reduce inhalational anaesthetic requirements when administered intravenously. Furthermore, these drugs can improve recovery quality. Preliminary investigations of subcutaneous dexmedetomidine administration in humans demonstrated a reduced haemodynamic impact if compared with the intravenous route suggesting that dexmedetomidine is adequately absorbed with both ad...
van Spijk JN, Beckmann K, Wehrli Eser M, Boxler M, Stirn M, Rhyner T, Kaelin D, Saleh L, Schoster A.Polymyxin B (PolyB) is used to treat endotoxemia in horses; neurologic and nephrogenic adverse effects occur in humans. Objective: To describe PolyB adverse effects in horses. Methods: Five healthy horses (ataxia 0/5), 1 horse with cervical osteoarthritis (ataxia 1/5). Methods: Prospective blinded randomized cross-over trial; 3-weeks wash out. Horses received PolyB (PolyB 6000 IU/kg IV, 7 doses q12h, n = 6) and PolyB/gentamicin (PolyB 6000 IU/kg IV, q12h 7 doses; gentamicin 10 mg/kg IV q24h 4 doses n = 4, or q12-24 h 5 doses because of an additional erroneous dose, n = 2). Daily n...
Emmerich IU.In 2021, one novel pharmaceutical agent for horses or food-producing animals was released on the German market, making the anti-haemorrhagic etamsylate (Hemosilate) available for horses, cattle, pigs, sheep, goats, dogs and cats, for the first time. The authorization of one established veterinary active ingredient was extended to an additional species: The endectocide eprinomectin (Eprecis) from the group of macrocyclic lactones was also approved for sheeps and goats. Additionally, two veterinary formulations with a new active substance content (bromhexine, tiamulin) and one active ingredient ...
Han L, Lan T, Lu Y, Zhou M, Li H, Lu H, Wang Q, Li X, Du S, Guan C, Zhang Y, Sahu SK, Qian P, Zhang S, Zhou H, Guo W, Chai H, Wang S, Liu Q, Liu H....The evolution of parasites is often directly affected by the host's environment. Studies on the evolution of the same parasites in different hosts are of great interest and are highly relevant to our understanding of divergence. Methods: Here we performed whole-genome sequencing of Parascaris univalens from different Equus hosts (horses, zebras and donkeys). Phylogenetic and selection analyses were performed to study the divergence and adaptability of P. univalens. Results: At the genetic level, multiple lines of evidence indicate that P. univalens is mainly separated into two clades (horse-de...
Vergara-Hernandez FB, Nielsen BD, Colbath AC.Osteoclasts are unique and vital bone cells involved in bone turnover. These cells are active throughout the individual's life and play an intricate role in growth and remodeling. However, extra-label bisphosphonate use may impair osteoclast function, which could result in skeletal microdamage and impaired healing without commonly associated pain, affecting bone remodeling, fracture healing, and growth. These effects could be heightened when administered to growing and exercising animals. Bisphosphonates (BPs) are unevenly distributed in the skeleton; blood supply and bone turnover rate determ...
Bhutia WD, Gupta S, Rani R, Batra K, Sethi K, Kumar S, Kumar R.Trypanosoma evansi is a causative agent of chronic wasting and fatal disease of livestock and wild animals known as surra. In this study, repurposing approach based on drug target was used to investigate the efficacy of kinase inhibitors (Barasertib-HQPA, BAR and Palbociclib isethionate, PAL) and protease inhibitors (Z-pro-prolinal, Z-PRO and Leupeptin hemisulphate, LEU) against T. evansi in HMI-9 medium. BAR, PAL and Z-PRO exhibited IC values of 13.52 µM, 0.6375 µM and 63.20 µM against T. evansi in terms of growth inhibition, in the contrary, LEU failed to exhibit a significant growth i...
Philip M, Karakka Kal AK, Subhahar MB, Karatt TK, Mathew B, Koshy SA.It is important to remember that performance-enhancing agents such as non-peptide growth hormone secretagogues present a significant risk of abuse. Ibutamoren (MK-0677) is a potent, long-acting, selective non-peptide growth hormone secretagogue that can be taken orally. Methods: This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration. Liquid chromatography/high-resolution mass spectrometry was used to determine the probable structures of the detected metabolites. Results: In this study, 22 metabolites of ibutamoren were identified (17 phase I and 5 p...
Reed R, Trenholme N, Skrzypczak H, Chang K, Ishikawa Y, Barletta M, Quandt J, Knych H, Sakai D.To compare the effects of hydromorphone and butorphanol in horses undergoing arthroscopy and describe the pharmacokinetics of hydromorphone in anesthetized horses. Methods: Randomized controlled clinical trial. Methods: A total of 40 adult horses admitted for elective arthroscopy. Methods: Horses were randomly assigned to be administered intravenous hydromorphone (0.04 mg kg-1; group TxH; n = 19) or butorphanol (0.02 mg kg-1; group TxB; n = 21) prior to surgery as part of a standardized anesthetic protocol. Pain was scored by two observers unaware of group assignment using the Equine Utrecht...
Stonex TM, Zibura AE, Andres M, Gilger BC, Oh A.To describe the use of 1% polidocanol as the sole treatment for a superficial orbital venous malformation in a horse. Methods: A 23-year-old Welsh Cobb cross gelding with a distensible swelling affecting the left lower eyelid, and secondary palpebral margin abnormalities and superficial keratitis. Methods: Color flow Doppler ultrasonography revealed non-pulsatile blood flow within the tortuous vascular network most consistent with a superficial orbital venous malformation appearing to involve the lateral palpebral and transverse facial veins. An intravenous catheter was placed within the later...
Hoffmann SL, Seminoff K, McKemie DS, Kass PH, Knych HK.Grapiprant is a prostaglandin E2 receptor antagonist that has been found to be an effective anti-inflammatory in dogs and that is devoid of some of the adverse effects associated with traditional NSAIDs that elicit their effects through inhibition of PGE2 production. Previously published reports have described the pharmacokinetics of this drug in horses when administered at 2 mg/kg; however, pharmacodynamic effects in this species have yet to be described. The objective of the current study was to describe the pharmacokinetics and pharmacodynamics of grapiprant at a higher dose. Eight horses...
Cock G, Blakeney Z, Hernandez JA, DeNotta S.Atlantoaxial (AA) cerebrospinal fluid (CSF) collection in standing horses utilizes the controlled narcotic morphine, thereby limiting feasibility in field practice settings. Objective: To compare AA CSF collection time and reaction scores in horses sedated with morphine-containing and opioid-free sedation protocols: detomidine + morphine (DM), detomidine + xylazine (DX), detomidine + detomidine (DD), detomidine alone (D0); To develop a novel method for assessing sedation in standing horses using open-source motion-tracking software. Methods: Six healthy adult horses. Methods: Randomi...
Knych HK, Stucker K, Gretler SR, Kass PH, McKemie DS.In humans, codeine is a commonly prescribed analgesic that produces its therapeutic effect largely through metabolism to morphine. In some species, analgesic effects of morphine have also been attributed to the morphine-6-glucuronide (M6G) metabolite. Although an effective analgesic, administration of morphine to horses produces dose-dependent neuroexcitation at therapeutic doses. Oral administration of codeine at a dose of 0.6 mg/kg has been shown to generate morphine and M6G concentrations comparable to that observed following administration of clinically effective doses of morphine, witho...
Kondampati KD, Saini SPS, Sidhu PK, Anand A, Kumar D, Beesam S, Bedi JS, Kaur R, Bhardwaj R.The pharmacokinetics of ampicillin-cloxacillin, given as single intravenously dose of 10 mg.kg-1 (5 mg.kg-1 of ampicillin plus 5 mg.kg-1 of cloxacillin) was examined in clinically presented Indian thoroughbred horses (n = 6) in order to design appropriate dosing strategies. Drug concentrations in plasma were determined by high performance liquid chromatography (HPLC) and pharmacokinetic parameters were derived by non-compartmental analysis using WinNonlin software. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ampicillin-cloxacillin against qualit...
Machin J, Brewer K, Morales-Briceno A, Fenger C, Maylin G, Tobin T.Zilpaterol is a β2-adrenergic agonist medication approved in certain countries as a cattle feed additive to improve carcass quality. Trace amounts of Zilpaterol can transfer to horse feed, yielding equine urinary "identifications" of Zilpaterol. These "identifications" occur because Zilpaterol is highly bioavailable in horses, resistant to biotransformation and excreted as unchanged Zilpaterol in urine, where it has a 5 day or so terminal half-life.In horses, urinary steady-state concentrations are reached 25 days (5 half-lives) after exposure to contaminated feed. Zilpaterol readily presen...
Tischmacher A, Wilford S, Allen K, Mitchell RD, Parkin T, Denoix JM.The objective of this retrospective study was to assess the safety and efficacy of a slow IV administration of 1mg/kg tiludronate in a large number of horses. Each horse that received at least one tiludronate-based treatment between 2006 and August 2019 at Virginia Equine Imaging or Fairfield Equine was included in the study. Concomitant medical treatments, preliminary nonsteroidal anti-inflammatory drug injection and potential side effects were recorded after each administration. Horses for which follow-up was available over 1 year were subject to clinical evolution assessment via lameness gr...
López-Sanromán FJ, Montes Freilich G, Gómez-Cisneros D, Izquierdo-Moreno J, Varela Del Arco M, Manso-Díaz G.The objective was to demonstrate walking locomotor pattern alterations after co-administration of acepromazine and morphine in horses. Six mature horses receiving four different treatments were used. Treatments consisted of a single dose of saline solution, 0.2 mg/kg bwt of morphine hydrochloride, 0.02 mg/kg bwt of acepromazine maleate, and a combination of 0.2 mg/kg bwt of morphine hydrochloride with 0.02 mg/kg bwt of acepromazine maleate. A three-dimensional accelerometric device was used to collect data. Walking tests were performed 10 min prior to injection, and then at 5, 10, 15, and 20 m...
Dube F, Hinas A, Roy S, Martin F, Åbrink M, Svärd S, Tydén E.The nematode Parascaris univalens is one of the most prevalent parasitic pathogens infecting horses but anthelmintic resistance undermines treatment approaches. The molecular mechanisms underlying drug activity and resistance remain poorly understood in this parasite since experimental in vitro models are lacking. The aim of this study was to evaluate the use of Caenorhabditis elegans as a model for P. univalens drug metabolism/resistance studies by a comparative gene expression approach after in vitro exposure to the anthelmintic drug ivermectin (IVM). Methods: Twelve adult P. univalens worms...
Ruíz-López P, Morgaz J, Quirós-Carmona S, Navarrete-Calvo R, Domínguez JM, Gómez-Villamandos RJ, Granados MM.Autonomic nervous system (ANS) activity can modify cardiovascular parameters in response to nociceptive stimuli or drugs in anesthetized animals. The aim of this study was to determine if a surgical nociceptive stimulus and morphine, ketamine, and dobutamine administration would modify ANS activity observed as a change in the mean parasympathetic tone activity (PTAm) in anesthetized horses. In 20 anesthetized horses, heart rate (HR), mean arterial pressure (MAP), and PTAm were monitored before and 1, 3, and 5 min after surgical incision, and before and 10 min after the administration of morphi...
Liepman RS, Swink JM, Habing GG, Boyaka PN, Caddey B, Costa M, Gomez DE, Toribio RE.Alterations in the gastrointestinal microbiota after antimicrobial therapy in horses can result in loss of colonization resistance and changes in bacterial metabolic function. It is hypothesized that these changes facilitate gastrointestinal inflammation, pathogen expansion and the development of diarrhea. The objectives of this study were to determine the effect of intravenous administration of antimicrobial drugs (ceftiofur, enrofloxacin, oxytetracycline) on equine fecal bacterial communities over time, to investigate whether those changes are detectable after 5 days of treatment and whether...
Elbourne M, Cawley A, Stanley S, Bowen C, Fu S.Equine urine analysis has evolved over time to detect thousands of urinary compounds for doping control in the horse racing industry. The longitudinal assessment of 3-methoxytyramine to tyramine ratio (3-MT/T) values in equine urine by GC-MS profiling was investigated to support the Racing NSW Equine Biological Passport (EBP) for detection of dopaminergic manipulation in racehorses. This involved comparison of routine urine samples to administration studies of Sinemet, a common Parkinson's disease medication containing levodopa. Using an endogenous reference compound (ERC) in a urinary ratio e...
Fungwithaya P, Boonchuay K, Narinthorn R, Sontigun N, Sansamur C, Petcharat Y, Thomrongsuwannakij T, Wongtawan T.Staphylococci are commensal bacteria and opportunistic pathogens found on the skin and mucosa. Sports animals are more prone to injury and illness, and we believe that antimicrobial agents might be extensively used for the treatment and cause the existence of antimicrobial-resistant (AMR) bacteria. This study aimed to investigate the diversity and AMR profile of staphylococci in sports animals (riding horses, fighting bulls, and fighting cocks) in South Thailand. Unassigned: Nasal (57 fighting bulls and 33 riding horses) and skin swabs (32 fighting cocks) were taken from 122 animals. Staphyloc...
Vercruysse EM, Narinx FP, Rives ACM, Sauvage AC, Grauwels MF, Monclin SJ.To describe bacterial isolates and associated antibiotic resistance from horses with ulcerative keratitis in Belgium. Methods: Medical records from horses with ulcerative keratitis presented to the ophthalmology service of the Veterinary teaching hospital of Liege, Belgium, between 2014 and 2021 were evaluated. Bacterial isolates were identified and VITEK® 2 (Biomérieux) provided antimicrobial susceptibility testing and resistance detection. Results: Two hundred eyes of 196 horses were sampled. Ninety-seven eyes had a positive bacterial culture (48.5%) and 139 bacterial isolates were identif...
Khusro A, Sahibzada MUK, Khan SU, Rajagopal R, Elghandour MMMY, Salem AZM, Kuppusamy P, Alcala-Canto Y, Tirado-González DN.Greenhouse gases emission from livestock is the major concern for the ecosystem. Despite the lower contribution of non-ruminants towards greenhouse gas emission as compared to the ruminants, the emission of methane (CH) gas from equines is expected to be increased in future due to its increasing population. Thus, it is essential to find or screen potential anti-methanogenic agent in a cost-effective and quicker manner. Considering this, the present investigation was aimed to analyze anti-methanogenic characteristic of bioactive compounds of safflower oil by targeting methanogenesis catalyzing ...
Gustafsson K, Tatz AJ, Britzi M, Dahan R, Sutton GA, Kelmer G.Eight horses underwent IVRLP at two occasions through a 23-gauge 2 cm long butterfly catheter. Regional anaesthesia of the ulnar, median and medial cutaneous antebrachial nerves was performed prior, and an 8 cm rubber tourniquet was placed on the proximal radius for 30 minutes following the infusion. The first infusion consisted of 2 g of amikacin sulphate and 10 mg of dexamethasone phosphate diluted with 0.9% NaCl to a total volume of 100 ml. The second perfusion was performed after a 2-week washout period, the same protocol was used but without dexamethasone phosphate. Synovial fluid s...
Porcello A, Gonzalez-Fernandez P, Jordan O, Allémann E.Hyaluronic acid (HA) constitutes a versatile chemical framework for the development of osteoarthritis pain treatment by means of injection in the joints, so-called viscosupplementation. Without appropriate physico-chemical tuning, such preparations are inherently hindered by prompt in vivo degradation, mediated by hyaluronidases and oxidative stress. To prolong hydrogel residence time and confer optimized product functionality, novel thermoresponsive nanoforming HA derivatives were proposed and characterized. Combined use of sulfo-dibenzocyclooctyne-PEG4-amine linkers and poly(N-isopropylacryl...
Ishii H, Shibuya M, So YM, Wong JKY, Ho ENM, Kusano K, Sone Y, Kamiya T, Wakuno A, Ito H, Miyata K, Yamada M, Leung GN.IOX4, a hypoxia-inducible factor stabilizer, is classified as a banned substance for horses in both horse racing and equestrian sports. We recently reported the pharmacokinetic profiles of IOX4 in horse plasma and urine and also identified potential monitoring targets for the doping control purpose. In this study, a long-term longitudinal analysis of IOX4 in horse hair after a nasoesophageal administration of IOX4 (500 mg/day for 3 days) to three thoroughbred mares is presented for the first time for controlling the abuse/misuse of IOX4. Six bunches of mane hair were collected at 0 (pre), ...
Tou K, Cawley A, Bowen C, Sornalingam K, Fu S.The conventional detection of exogenous drugs in equine doping samples has been used for confirmation and subsequent prosecution of participants responsible. In recent years, alternative methods using indirect detection have been investigated due to the expanding number of pharmaceutical agents available with the potential of misuse. The monitoring of endogenous biomarkers such as hydrocortisone (HC) has been studied in equine urine with an international threshold of 1 μg/ml established; however, there is no current threshold for equine plasma. The aim of this research was to investigate pl...
Lyons ET, Drudge JH, Tolliver SC.Experimentally induced infections of Parascaris equorum in worm-free pony foals required 14 to 17 days for migration of the larvae through the liver and lungs, and 79 to 110 days to become gametogenically functional. Treatment of experimentally infected or naturally exposed foals during the parenteral phase of development, using levamisole at 8 mg/kg, a mixture of levamisole at 8 mg/kg plus piperazine at 88 mg base equivalent/kg, or dl-tetramisole at 10 mg/kg, was quite efficacious in (1) reducing the number of P. equorum larvae recovered from the small intestines of the foals at necropsy, or ...
Cohen ND, Slovis NM, Giguère S, Baker S, Chaffin MK, Bernstein LR.Macrolide-resistant isolates of Rhodococcus equi are emerging, prompting the search for clinically effective alternative antimicrobials. Objective: The proportion of foals with ultrasonographic evidence of pneumonia presumed to be caused by R. equi that had a successful outcome when administered gallium maltolate (GaM) PO would not be more than 10% inferior (ie, lower) than that of foals receiving standard treatment. Methods: Fifty-four foals with subclinical pulmonary abscesses among 509 foals at 6 breeding farms in Kentucky. Methods: Controlled, randomized, prospective noninferiority study. ...
Steffey EP, Pascoe PJ, Woliner MJ, Berryman ER.To quantitate dose- and time-related anesthetic-sparing effects of xylazine hydrochloride (XYL) during isoflurane-induced anesthesia in horses and to characterize selected physiologic responses of anesthetized horses to administration of XYL. Methods: 6 healthy adult horses. Methods: Horses were anesthetized 2 times to determine the minimum alveolar concentration (MAC) of isoflurane in O2 and to characterize the anesthetic-sparing effect (MAC reduction) after IV administration of XYL (0.5 and 1 mg/kg of body weight, random order). Selected measures of cardiopulmonary function, blood glucose co...
Zielinski K, Sekula B, Bujacz A, Szymczak I.Serum albumin, the most abundant transport protein of mammalian blood, interacts with various nonsteroidal anti-inflammatory drugs (NSAIDs) affecting their disposition, metabolism, and excretion. A big group of chiral NSAIDs transported by albumin, profens, is created by derivatives of 2-arylpropionic acid. The chiral center in the structures of profens is adjacent to the carboxylate moiety and often determines different pharmacological properties of profen enantiomers. This study describes crystal structures of two albumins, isolated from equine and leporine serum, in complexes with three pro...
Sweeney CR, Soma LR, Maxson AD, Thompson JE, Holcombe SJ, Spencer PA.The effects of furosemide on the racing times of 79 horses without exercise-induced pulmonary hemorrhage (EIPH) and 52 horses with EIPH were investigated. Racing times were adjusted to 1-mile equivalent racing times by 2 speed handicapping methods, and analysis of covariance was used to adjust actual racing times by winning time and distance for each race. All 3 methods of determining racing time indicated that geldings without EIPH had significantly faster racing times (P less than 0.05) when given furosemide before racing than when furosemide was not given before racing. Females and colts wi...
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...
Williams DC, Aleman MR, Brosnan RJ, Fletcher DJ, Holliday TA, Tharp B, Kass PH, Steffey EP, LeCouteur RA.Previous study of the diagnostic validity of electroencephalography (EEG) to detect abnormalities in equine cerebral cortical function relied on the administration of various drugs for sedation, induction, and maintenance of general anesthesia but used identical criteria to interpret recordings. Objective: To determine the effects of 2 inhalation anesthetics on the EEG of healthy horses. Methods: Six healthy horses. Methods: Prospective study. After the sole administration of one of either isoflurane or halothane at 1.2, 1.4, and 1.6 times the minimum alveolar concentration, EEG was recorded d...
Gozalo-Marcilla M, Luna SP, Crosignani N, Filho JNP, Possebon FS, Pelligand L, Taylor PM.To evaluate intravenous (IV) detomidine with methadone in horses to identify a combination which provides sedation and antinociception without adverse effects. Methods: Randomized, placebo-controlled, blinded, crossover. Methods: A group of eight adult healthy horses aged (mean ± standard deviation) 7 ± 2 years and 372 ± 27 kg. Methods: A total of six treatments were administered IV: saline (SAL); detomidine (5 μg kg; DET); methadone (0.2 mg kg; MET) alone or combined with detomidine [2.5 (MLD), 5 (MMD) or 10 (MHD) μg kg]. Thermal, mechanical and electrical nociceptive thresholds were mea...
Shilo Y, Britzi M, Eytan B, Lifschitz T, Soback S, Steinman A.Tramadol is a centrally acting analgesic drug that has been used clinically for the last two decades to treat moderate to moderately severe pain in humans. The present study investigated tramadol administration in horses by intravenous, intramuscular, oral as immediate-release and oral as sustained-release dosage-form routes. Seven horses were used in a four-way crossover study design in which racemic tramadol was administered at 2 mg/kg by each route of administration. Altogether, 23 blood samples were collected between 0 and 2880 min. The concentration of tramadol and its M1 metabolite were ...
Ho EN, Leung DK, Leung GN, Wan TS, Wong AS, Wong CH, Soma LR, Rudy JA, Uboh C, Sams R.Administration studies of levamisole in horses were carried out using two different levamisole preparations, namely, levamisole hydrochloride oral bolus and levamisole phosphate injectable solution. These preparations were analysed in detail for the presence of aminorex-like impurities. Both levamisole preparations were found to contain 1-(2-mercaptoethyl)-4-phenyl-2-imidazolidinone (I) and 4-phenyl-2-imidazolidinone (II) as degradation impurities, but neither aminorex nor rexamino was detected in these preparations. After the administration of these preparations to horses, aminorex, rexamino,...
D'Arcy-Moskwa E, Noble GK, Weston LA, Boston R, Raidal SL.Newer NSAIDs that more selectively target the induced isoform of the cyclooxygenase enzyme (COX2) activity might reduce adverse effects while preserving therapeutic benefits of these drugs. Objective: To compare the effect of oral administration of multiple dose rates of meloxicam and phenylbutazone (PBZ) on gastric mucosal integrity in horses. Methods: Twenty-five light breed horses. Methods: In vivo toxicity study. Horses were randomly assigned to 5 treatment groups, receiving placebo, PBZ (4.4 mg/kg PO q12h day 1, 2.2 mg/kg PO q12h for 4 days, 2.2 mg/kg PO q24h for 9 days), or 3 dose rates ...
Chan GH, Ho EN, Leung DK, Wong KS, Wan TS.The use of anabolic androgenic steroids (AAS) is prohibited in both human and equine sports. The conventional approach in doping control testing for AAS (as well as other prohibited substances) is accomplished by the direct detection of target AAS or their characteristic metabolites in biological samples using hyphenated techniques such as gas chromatography or liquid chromatography coupled with mass spectrometry. Such an approach, however, falls short when dealing with unknown designer steroids where reference materials and their pharmacokinetics are not available. In addition, AASs with fast...
Lyons ET, Tolliver SC, Kuzmina TA, Collins SS.The activity of three anthelmintics (fenbendazole-FBZ; oxibendazole-OBZ; and pyrantel pamoate-PRT) was ascertained against the ascarid Parascaris equorum in horse foals on eight farms in Central Kentucky (2009-2010) in field tests. A total of 316 foals were treated, and 168 (53.2%) were passing ascarid eggs on the day of treatment. Evaluation of drug efficacy was determined qualitatively by comparing the number of foals passing ascarid eggs in their feces before and after treatment. The main purpose was to obtain data on current activity of these compounds against ascarids. Additionally, the o...
Pérez R, Cabezas I, García M, Rubilar L, Sutra JF, Galtier P, Alvinerie M.A study was undertaken in order to evaluate and compare plasma disposition kinetic parameters of moxidectin and ivermectin after oral administration of their commercially available preparations in horses. Ten clinically healthy adult horses, weighing 390-446 kg body weight (b.w.), were allocated to two experimental groups of five horses. Group I was treated with an oral gel formulation of moxidectin (MXD) at the manufacturers recommended therapeutic dose of 0.4 mg/kg bw. Group II was treated with an oral paste formulation of ivermectin (IVM) at the manufacturers recommended dose of 0.2 mg/kg b...
Cooper LG, Caffe G, Cerutti J, Nielsen MK, Anziani OS.Macrocyclic lactones are the most widely used drugs for the control of gastrointestinal nematodes of horses in Argentina. Ivermectin and moxidectin are used as broad spectrum anthelmintics and although there are several international reports on the resistance of Parascaris spp., the resistance status of the local nematode population is largely unknow. This report informs a case of suboptimal efficacy to both drugs to control Parascaris spp in foals in central Argentina. In February 2018, routine fecal parasite egg counts showed a moderate-high number of Parascaris spp eggs (mean = 680 eggs p...
Seo JP, Son WG, Gang S, Lee I.This study was performed to evaluate the sedative and analgesic effects of xylazine (X) and tramadol (T) intravenously (IV) administered to horses. Six thoroughbred saddle horses each received X (1.0 mg/kg), T (2.0 mg/kg), and a combination of XT (1.0 and 2.0 mg/kg, respectively) IV. Heart rate (HR), respiratory rate (RR), rectal temperature (RT), indirect arterial pressure (IAP), capillary refill time (CRT), sedation, and analgesia (using electrical stimulation and pinprick) were measured before and after drug administration. HR and RR significantly decreased from basal values with X and XT t...
Thurmon JC, Steffey EP, Zinkl JG, Woliner M, Howland D.Xylazine given IV at doses of 0.5, 1.0, and 1.5 mg/kg to mares caused a significant (P less than 0.05) dose-related increase in serum glucose concentration and urine volume. Serum glucose concentrations as much as 150 mg/dl were recorded in mares after they were given the largest xylazine dose. The greatest urine volume, similar to changes in peak glucose concentration, always occurred during the first hour after dosing with xylazine and averaged 1.82, 3.93, and 5.68 ml/kg/hour after the 0.5-, 1.0-, and 1.5-mg/kg doses, respectively, were given. Urine osmolality and specific gravity were signi...
Merritt AM, Burrow JA, Hartless CS.To evaluate the effect on equine duodenal motility of some analgesic agents commonly used to treat colic. Methods: 4 healthy adult healthy horses--2 mares and 2 geldings--which were carrying an indwelling gastric cannula made of silastic rubber. One horse also carried 2 long-term indwelling bipolar electrodes that had been sutured onto the duodenum and jejunum. Methods: To ensure an empty stomach, solid food was withheld from horses for around 20 hours prior to an experiment. Using videoendoscopic guidance, an 8-F catheter with 3 small, discrete pressure sensors was passed through the gastric ...
Regan FH, Hockenhull J, Pritchard JC, Waterman-Pearson AE, Whay HR.To identify pain-related behaviour in working donkeys in order to assist their owners and veterinarians to recognise and manage pain. Objective: To identify general and specific behaviours associated with pain or its relief using a trial with the nonsteroidal anti-inflammatory drug meloxicam (Metacam). Methods: Observer-blinded, placebo-controlled trial. Methods: Forty adult male working donkeys with common clinical abnormalities were randomly assigned to receive either a single loading dose of meloxicam (1.2 mg/kg bwt per os; n = 20) or a placebo (30 mg honey/250 ml water per os; n = 20...
Suzuki T, Kobayashi H, Kawasaki Y, Okazuka K, Hatano K, Fujiwara S, Oh I, Ohmine K, Kanda Y.Anti-thymocyte globulin (ATG) is a key drug in immunosuppressive therapy for patients with aplastic anemia. The mainstay of ATG therapy had been a horse ATG (hATG) formulation, Lymphoglobulin or ATGAM, but Lymphoglobulin was recently discontinued, and Thymoglobulin, a rabbit ATG (rATG) formulation, is currently used as the first-line drug in many countries, including Japan. However, a recent randomized clinical trial reported significantly unfavorable outcomes associated with the use of rATG regimens. We retrospectively analyzed clinical outcomes of adult patients with moderate to severe aplas...
Matthews NS, Hartsfield SM, Cornick JL, Williams JD, Beasley A.Six combinations of injectable anesthetic agents were administered to six adult horses in a Latin square design. The drug combinations were xylazine-ketamine, xylazine-butorphanol-ketamine, xylazine-tiletamine-zolazepam, xylazine-butorphanol-tiletamine-zolazepam, detomidine-ketamine, and detomidine-butorphanol-ketamine. Measured variables were heart rate, respiratory rate, systolic blood pressure, arterial pH (pHa), PaCO2, PaO2, recumbency time, and number of attempts necessary to stand. Quality of induction and recovery, muscle relaxation, and response to stimulus were evaluated subjectively....
Ho EN, Yiu KC, Wan TS, Stewart BD, Watkins KL.Anti-diabetics such as sulfonylurea and thiazolidinedione derivatives are hypoglycemic drugs used for the treatment of diabetes. However, they can also be used as a stopper in horseracing. This paper describes a convenient method for the separation and simultaneous detection of 10 anti-diabetic drugs (namely glipizide, glibenclamide, glimepiride, gliclazide, tolazamide, tolbutamide, nateglinide, repaglinide, rosiglitazone and pioglitazone) in equine plasma and urine by LC-MS-MS. Methods: The anti-diabetics were isolated from equine plasma and urine by liquid-liquid extraction with 1,2-dichloro...
Valverde A.Alpha-2 agonists, such as xylazine, clonidine, romifidine, detomidine, medetomidine, and dexmedetomidine, are potent analgesic drugs that also induce physiologic and behavioral changes, such as hypertension, bradycardia, atrioventricular block, excessive sedation and ataxia, all of which can potentially limit their systemic use as analgesics in some clinical cases. The use of medetomidine and dexmetomidine has been introduced for equine anesthesia/analgesia, and although not approved in this species, their increased specificity for alpha-2 receptors may offer some potential advantages over the...
Soma LR, Uboh CE, Liu Y, Li X, Robinson MA, Boston RC, Colahan PT.This study investigated and compared the pharmacokinetics of intra-articular (IA) administration of dexamethasone sodium phosphate (DSP) into three equine joints, femoropatellar (IAS), radiocarpal (IAC), and metacarpophalangeal (IAF), and the intramuscular (IM), oral (PO) and intravenous (IV) administrations. No significant differences in the pharmacokinetic estimates between the three joints were observed with the exception of maximum concentration (Cmax ) and time to maximum concentration (Tmax ). Median (range) Cmax for the IAC, IAF, and IAS were 16.9 (14.6-35.4), 23.4 (13.5-73.0), and 46.9...
Grimmer NM, Gimbar RP, Bursua A, Patel M.The literature regarding rhabdomyolysis secondary to illicit drug use is sparse. Clenbuterol is a bronchodilator approved for veterinary use, which in high doses can increase protein deposition and lipolysis similarly to anabolic steroids, and is thereby abused for bodybuilding and weight loss effects. Clenbuterol has previously been described in case reports to be cardiotoxic, with patient presentations similar to overdoses of sympathomimetic substances, but reports of rhabdomyolysis are limited to a single case series in horses. Methods: We report the first case of rhabdomyolysis secondary t...
Stratton-Phelps M, Wilson WD, Gardner IA.To determine whether foals with pneumonia that were treated with erythromycin, alone or in combination with rifampin or gentamicin, had a higher risk of developing adverse effects, compared with foals treated with trimethoprim-sulfamethoxazole (TMS), penicillin G procaine (PGP), or a combination of TMS and PGP (control foals). Methods: Retrospective study. Methods: 143 foals < 240 days old. Methods: Information on age, sex, breed, primary drug treatment, total days of treatment with the primary drug, and whether the foal developed diarrhea, hyperthermia, or respiratory distress was obtained...
Fungwithaya P, Boonchuay K, Narinthorn R, Sontigun N, Sansamur C, Petcharat Y, Thomrongsuwannakij T, Wongtawan T.Staphylococci are commensal bacteria and opportunistic pathogens found on the skin and mucosa. Sports animals are more prone to injury and illness, and we believe that antimicrobial agents might be extensively used for the treatment and cause the existence of antimicrobial-resistant (AMR) bacteria. This study aimed to investigate the diversity and AMR profile of staphylococci in sports animals (riding horses, fighting bulls, and fighting cocks) in South Thailand. Unassigned: Nasal (57 fighting bulls and 33 riding horses) and skin swabs (32 fighting cocks) were taken from 122 animals. Staphyloc...
Piras C, Gugliandolo E, Castagna F, Palma E, Britti D.Ivermectin has a wide number of many diverse functions. Certainly, it is irreplaceable for the treatment of parasitic pathologies in both human and veterinary medicine, and the latter represents the major field of its application. It has been called the "drug for the world's poor" because of its role as a saviour for those living on the margins of society, in underdeveloped areas afflicted by devastating and debilitating diseases, such as Onchocerciasis and Lymphatic filariasis. It showed huge, unexpected potential as an antibacterial (Chlamydia trachomatis and mycobacteria), and it has antivi...
Kaukinen H, Aspegrén J, Hyyppä S, Tamm L, Salonen JS.The objective of the study was to determine the absorption, bioavailability and sedative effect of detomidine administered to horses as an oromucosal gel compared to intravenous and intramuscular administration of detomidine injectable solution. The study was open and randomized, with three sequences crossover design. Nine healthy horses were given 40 μg/kg detomidine intravenously, intramuscularly or administered under the tongue with a 7-day wash-out period between treatments. Blood samples were collected before and after drug administration for the measurement of detomidine concentration...
Pirie RS, Mueller HW, Engel O, Albrecht B, von Salis-Soglio M.Ciclesonide is a glucocorticoid prodrug, already registered for human use. Due to its mode of action and inhaled route of administration, it was considered an appropriate treatment option for horses with severe equine asthma. Although the efficacy of inhaled ciclesonide has been demonstrated in horses with asthma exacerbations under controlled mouldy hay challenge conditions, it has not yet been reported under field conditions. Objective: To assess the effectiveness and safety of inhaled ciclesonide for the treatment of severe equine asthma. Methods: Prospective, multicentre, placebo-controlle...
