The placebo effect in horses refers to the phenomenon where a horse experiences a perceived or actual improvement in condition following a treatment that has no therapeutic effect. This effect is often observed in clinical trials and studies where control groups receive a placebo treatment to assess the efficacy of a new drug or therapy. Understanding the placebo effect in horses is important for designing rigorous equine research studies, as it helps distinguish between the actual effects of a treatment and psychological or physiological responses that are not directly caused by the treatment itself. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, implications, and methodologies for accounting for the placebo effect in equine research.
Read JR, Boston RC, Abraham G, Bauquier SH, Soma LR, Nolen-Walston RD.To determine whether prolonged administration of clenbuterol results in tachyphylaxis, specifically regarding its bronchoprotective properties and effect on sweating in horses. Methods: 8 Thoroughbreds with inflammatory airway disease. Methods: In a crossover design, horses received clenbuterol (0.8 μg/kg, p.o., q 12 h) or placebo for 21 days, with a washout period of ≥ 30 days between the 2 treatments. Airway reactivity was evaluated by use of flowmetric plethysmography and histamine broncho-provocation before (day 0; baseline) and every 7 days after the start of treatment. Sweat function ...
Nieto JE, Aleman M, Anderson JD, Fiack C, Snyder JR.To assess gene expressions of cyclooxygenase-1 and -2 in oral, glandular gastric, and urinary bladder mucosae and determine the effect of oral administration of phenylbutazone on those gene expressions in horses. Methods: 12 healthy horses. Methods: Horses were allocated to receive phenylbutazone or placebo (6 horses/group); 1 placebo-treated horse with a cystic calculus was subsequently removed from the study, and those data were not analyzed. In each horse, the stomach and urinary bladder were evaluated for ulceration via endoscopy before and after experimental treatment. Oral, glandular gas...
Venner M, Rödiger A, Laemmer M, Giguère S.Mass antimicrobial treatment of foals with small ultrasonographic pulmonary lesions is common on farms with endemic disease caused by Rhodococcus equi. The objectives of this study were to compare the relative efficacy of three antimicrobial protocols for the treatment of pulmonary abscesses on a farm with endemic infections caused by R. equi and to determine the frequency of spontaneous resolution of subclinical pulmonary lesions. Foals with ultrasonographic evidence of pulmonary abscesses ≥ 1.0 cm in diameter (n=128) were randomly allocated to one of four equal treatment groups. Animals wi...
Cayzer J, Hedderley D, Gray S.Lyophilised products from green-lipped mussel (Perna canaliculus[LPPC]) are used to orally treat horses with osteoarthritis (OA). However, no randomised, controlled or double-blinded studies on the efficacy of this treatment in horses have been reported to date. Objective: To investigate the effects of a unique LPPC (Biolane)(1) in improving clinical signs of OA in the fetlock. Methods: Data were analysed from 26 horses with primary fetlock lameness in a controlled, randomised and double-blinded, multi-centre clinical trial. The study design was a partial crossover with a washout period and co...
Chaffin MK, Cohen ND, Martens RJ, O'Conor M, Bernstein LR.To determine the chemoprophylactic effect of gallium maltolate on the cumulative incidence of pneumonia caused by Rhodococcus equi infection in foals. Methods: 483 foals born and raised on 12 equine breeding farms with a history of endemic R equi infections. Methods: Group 1 foals were treated with a placebo and group 2 foals were treated with gallium maltolate (approx 30 mg/kg, PO, q 24 h) during the first 2 weeks after birth. Foals were monitored for development of pneumonia attributable to R equi infection and for adverse effects of gallium maltolate. Results: There were no significant diff...
Fjordbakk CT, Haga HA.To assess the efficacy of a commercially available topical vapocoolant spray in reducing responses to arthrocentesis of the middle carpal (MC) and metacarpophalangeal (MCP) joints and jugular vein catheterization in unsedated horses. Methods: 8 healthy research horses. Methods: Arthrocentesis of both MC and MCP joints and bilateral jugular vein catheterization were performed in each horse. Immediately prior to skin penetration, 1 randomly selected MC joint, MCP joint, and jugular vein were sprayed with a vapocoolant liquid (intervention product), and the contralateral MC joint, MCP joint, and ...
Notin C, Vallon L, Desbordes F, Leleu C.Intense physical exercise produces an excess of reactive oxygen species which can disturb the antioxidant/oxidant balance of the horse in training. Several classes of antioxidant dietary compounds have been suggested to provide health benefits and there is evidence that consumption of these products leads to a reduction in the expression of various pro-inflammatory and/or oxidative stress biomarkers. The recent development of a new galenic system allows the oral delivery of the antioxidant enzyme: superoxide dismutase (SOD). This has been developed from a specific melon variety with a particul...
Buchholz BM, Murdock A, Bayly WM, Sides RH.The antifibrinolytic, 6-aminohexanoic acid, also named aminocaproic acid (ACA), has been used empirically as a treatment for exercise-induced pulmonary haemorrhage (EIPH) on the unsubstantiated basis that transient coagulation dysfunction may contribute to its development. Objective: To assess the effect of ACA on bronchoalveolar lavage fluid (BALF) erythrocyte counts in horses performing treadmill exercise at an intensity greater than that needed to reach maximal oxygen consumption. Methods: Eight Thoroughbreds were exercised to fatigue 3 times on a 10% inclined treadmill at a speed for which...
Gerber V, Schott Ii HC, Robinson NE.Efficacy of medications for recurrent airway obstruction is typically tested using clinical, cytological and lung function examinations of severely affected animals. These trials are technically challenging and may not adequately reflect the spectrum of disease and owner complaints encountered in clinical practice. Objective: To determine if owners of horses with chronic airway disease are better able to detect drug efficacy than a veterinarian who clinically examines horses infrequently. Methods: In a double-blinded randomised controlled trial, owners and a veterinarian compared the efficacy ...
McClure S, Sibert G, Hallberg J, Bade D.The efficacy and safety of sustained release ceftiofur administered twice, 4 days apart, for treatment of horses with naturally acquired Streptococcus equi subsp. zooepidemicus (Strep. zoo.) pneumonia was evaluated in a multicenter, placebo-controlled, double-blinded, randomized clinical trial. The study included 373 horses (278 treated and 95 placebos) with naturally acquired pneumonia. Inclusion in the statistical analyses for treatment efficacy for Strep. zoo. required recovery of ≥10(4) CFU/mL of Strep. zoo. on the primary isolation plate which resulted in 201 cases (145 treated and 56 p...
van den Boom R, Kempenaars M, van Oldruitenborgh-Oosterbaan MM.Insect bite hypersensitivity (IBH) is the most common cause of pruritus in horses and is a serious welfare issue for affected animals. In this study, the effect of a topical phytogenic ointment on the healing of cutaneous lesions was investigated in a double-blind trial involving 26 horses with I B H. The number of lesions and their total surface area were recorded on days 0, 7, and 21 in horses treated for 3 weeks with either verum or placebo ointment. After unblinding of treatment assignment, the horses that had been treated with the placebo ointment received the verum preparation for an add...
Sturgill TL, Giguère S, Franklin RP, Cohen ND, Hagen J, Kalyuzhny AE.The objectives of the present study were to determine if administration of inactivated parapoxvirus ovis (IPPVO) can decrease the cumulative incidence of pneumonia and increase the number of IFN-γ- and IL-4-secreting cells among foals. Fifty-nine foals were randomly assigned to 2 treatment groups (IPPVO or placebo) prior to birth. At 24-48 h of age, foals received 2 ml of either IPPVO or a placebo by intramuscular injection. Injections were repeated 24h and 8 days later. The number of IFN-γ- and IL-4-secreting cells was measured using a validated ELISPOT assay on blood mononuclear cells coll...
Crane MA, Khallaayoune K, Scantlebury C, Christley RM.Gastro-intestinal parasitism has been identified as a significant cause of disease in working equids in many countries. This randomized triple-blind trial was designed to assess the impact of an anthelmintic treatment programme (using oral ivermectin and fenbendazole) comparing treated and placebo control populations of working donkeys, mules and horses in field conditions in Morocco. In particular, we assessed animal body weight and condition score, together with a questionnaire-based owner evaluation of number of subjective animal health parameters. Faecal worm egg count was also measured. R...
Gardner RB, White GW, Ramsey DS, Boucher JF, Kilgore WR, Huhtinen MK.To determine whether sublingual detomidine gel administration to horses would be effective in providing an appropriate degree of sedation and restraint to facilitate completion of veterinary and husbandry procedures under field conditions. Methods: Multicenter, prospective, randomized, blinded, placebo-controlled clinical study. Methods: 270 client-owned horses known to require sedation or strong restraint to enable veterinary and husbandry procedures to be performed. Methods: Horses randomly received a single dose of detomidine gel (0.04 mg/kg [0.018 mg/lb]) or placebo gel administered sublin...
Müller J, Feige K, Wunderlin P, Hödl A, Meli ML, Seltenhammer M, Grest P, Nicolson L, Schelling C, Heinzerling LM.Melanoma is a disease with high incidence in gray horses and has limited therapeutic options in metastatic disease. Gene therapy has shown some success in animal models and human patients. A randomized double-blind, placebo-controlled study was conducted to investigate 2 treatment options using cytokine-encoding plasmid DNA in horses with metastatic melanoma to induce immunologic antitumor effects. Adult gray horses with spontaneously occurring metastatic melanoma (n=26) were included in the study. Treatment of 26 gray horses with metastatic melanoma consisted of interleukin-18-encoding plasmi...
Gorman JK, Gabriel M, MacLachlan NJ, Nieto N, Foley J, Spier S.This pilot study evaluated protection of an equine autogenous bacterin-toxoid vaccine against Corynebacterium pseudotuberculosis infection. Twenty-four BALB/c mice were inoculated with two doses of bacterin-toxoid vaccine or two injections of a placebo. Clinical, microbiologic, and pathologic outcomes were assessed after intradermal infection with one of two equine-origin C. pseudotuberculosis strains. Mice receiving bacterin-toxoid from fast-growing C. pseudotuberculosis showed significant protection from challenge infection, as evidenced by a higher survival rate, fewer gross and histopathol...
Christen-Clottu O, Klocke P, Burger D, Straub R, Gerber V.Equine sarcoids (ES) are common, difficult to treat, and have high recurrence rates. Viscum album extracts (VAE) are used in human cancer treatment. Objective: That therapy with VAE (Iscador P) is effective in the treatment of ES. Methods: Fifty-three horses (444 ES); 42 were treated with VAE or placebo as monotherapy; 11 were treated with VAE or placebo after selective excision of ES. Methods: Prospective, randomised, blinded, clinical trial. Horses were randomly assigned to treatment (VAE; n=32) or control group (Placebo; n=21). One milliliter of VAE (Iscador P) in increasing concentrations ...
van den Boom R, Driessen F, Streumer SJ, Sloet van Oldruitenborgh-Oosterbaan MM.Insect bite hypersensitivity (IBH) is most often caused by Culicoides spp., although other insect species are also thought to play a role in causing this disease. The disease has been reported to occur in most countries, with a prevalence of up to 28% in some countries in some breeds. The only truly effective therapy currently available is to prevent horses from coming into contact with Culicoides midges, which can be achieved by stabling horses during certain times of the day or by covering them with insect blankets. The effect of a new dietary supplement containing vitamins, polypeptides, an...
Gough MR, Thibaud D, Smith RK.Tiludronate regulates bone remodelling through a decrease of the resorptive process and should therefore ameliorate the remodelling processes active in osteoarthritis of the distal tarsal joints ('bone spavin') and alleviate pain associated with abnormal bone lysis. Objective: To confirm the efficacy of tiludronate, administered as a single infusion at a dose of 1 mg/kg bwt, in the treatment of bone spavin in the horse. Methods: A double blind placebo controlled trial on 108 clinical cases of bone spavin was undertaken. The lameness score of the lamest limb was assessed following distal tarsal...
Rüfenacht S, Roosje PJ, Sager H, Doherr MG, Straub R, Goldinger-Müller P, Gerber V.Chorioptes bovis infestation is a common cause of pastern dermatitis in the horse, with a predilection in draft horses and other horses with thick hair 'feathers' on the distal limbs. The treatment of this superficial mite is challenging; treatment failure and relapse are common. Furthermore, C. bovis infestation may affect the progression of chronic pastern dermatitis (also known as chronic proliferative pastern dermatitis, chronic progressive lymphoedema and dermatitis verrucosa) in draft horses, manifesting with oedema, lichenification and excessive skin folds that can progress to verruci...
Petersson KH, Burr DB, Gomez-Chiarri M, Petersson-Wolfe CS.Horses have an increased susceptibility to infection because of a decline in immune function with advancing age. Vitamin E has been found to play a key role in normal immune system function. The purpose of the study was to examine the effect of vitamin E supplementation on immune function and response to vaccination in older horses. Predominantly older horses (18.9 +/- 1.3 yr, range 7 to 26 yr; 523 +/- 38 kg of BW) were supplemented orally once daily for 16 wk with either all-rac-alpha-tocopheryl acetate (15 IU/kg of BW; n = 8) or a placebo (n = 8). One horse from each group was removed from t...
Gupta RC, Canerdy TD, Skaggs P, Stocker A, Zyrkowski G, Burke R, Wegford K, Goad JT, Rohde K, Barnett D, DeWees W, Bagchi M, Bagchi D.The present investigation evaluated arthritic pain in horses receiving daily placebo, undenatured type II collagen (UC-II) at 320, 480, or 640 mg (providing 80, 120, and 160 mg active UC-II, respectively), and glucosamine and chondroitin (5.4 and 1.8 g, respectively, bid for the first month, and thereafter once daily) for 150 days. Horses were evaluated for overall pain, pain upon limb manipulation, physical examination, and liver and kidney functions. Evaluation of overall pain was based upon a consistent observation of all subjects during a walk and a trot in the same pattern on the same sur...
Bosch G, Moleman M, Barneveld A, van Weeren PR, van Schie HT.The repair process of tendon injuries, which are common in both human and equine athletes, is slow and the quality of the repair tissue is often inferior to the original tendon tissue, which frequently leads to re-injury. The relatively poor vascularization of tendons is considered to be one of the reasons for their limited healing potential. Recently, platelet-rich plasma (PRP), an autologous concentrate of platelets, rich in growth factors, has been shown to enhance the repair process of injured tendons. This effect has been ascribed to the high levels of growth factors in PRP, several of wh...
Olsén L, Bondesson U, Broström H, Olsson U, Mazogi B, Sundqvist M, Tjälve H, Ingvast-Larsson C.Horses with insect bite hypersensitivity (IBH) have difficulty in completely avoiding allergens, so effective treatment options are required. A randomised, placebo controlled and double blinded field study was conducted to determine the pharmacokinetics and efficacy in reducing dermatitis of the antihistamine cetirizine given orally at 0.4 mg/kg twice daily for 3 weeks. The influence of protection blankets and stabling were also investigated. The estimated maximum plasma concentration (C(max)) and trough plasma concentration of cetirizine were 135 ng/mL and 18 ng/mL, respectively. There was no...
Bosch G, René van Weeren P, Barneveld A, van Schie HT.The effectiveness of new therapies to treat tendon injuries is difficult to determine and is often based on semi-quantitative methods, such as grey level analysis of ultrasonographic images or subjective pain scores. The alternatives are costly and long-lasting end-stage studies using experimental animals. In this study, a method of ultrasonographic tissue characterisation (UTC), using mathematical analysis of contiguous transverse ultrasonographic images, was used for intra-vital monitoring of the healing trajectory of standardised tendon lesions treated with platelet rich plasma (PRP) or pla...
Perez-Moreno CI, Couëtil LL, Pratt SM, Ochoa-Acuña HG, Raskin RE, Russell MA.The objective was to quantify the effect of furosemide and carbazochrome on exercise-induced pulmonary hemorrhage (EIPH) in Standardbred horses using red blood cell count and hemoglobin concentration in bronchoalveolar lavage (BAL) fluid. Six healthy Standardbred horses with prior evidence of EIPH performed a standardized treadmill test 4 h after administration of placebo, furosemide, or furosemide-carbazochrome combination. Red blood cell (RBC) counts and hemoglobin concentrations were determined on the BAL fluid. The RBC count in BAL ranges were (2903-26,025 cells/microL), (45-24,060 cells/m...
Levine DG, Epstein KL, Neelis DA, Ross MW.To determine whether topical application of 1% diclofenac sodium cream would decrease inflammation at sites of IV regional limb perfusion (IVRLP) in healthy horses. Methods: 6 healthy adult horses (12 forelimbs). Methods: Bilateral IVRLP with 2.5 g of amikacin sulfate was performed twice in each horse, with 24 hours between each session. Horses were treated with topical 1% diclofenac liposomal cream (treated limbs) or a placebo cream (control limbs). All injection sites were evaluated before the first IVRLP session and 24 hours after the second session by means of ultrasonographic examination ...
Carmona JU, Argüelles D, Deulofeu R, Martínez-Puig D, Prades M.The aim of this study was to evaluate the clinical and biochemical effects of the administration of oral hyaluronan (Hyal-Joint [HJ]) on young horses with osteochondrosis (OC). Our hypotheses were that HJ administration is safe, would decrease the degree of synovial effusion and the concentration of nitric oxide (NO) and prostaglandin E2 (PGE2) in synovial fluid, and would increase the concentration of hyaluronic acid (HA) in plasma and synovial fluid. Eleven young horses with tarsocrural OC were included in a randomised, double-blinded, placebo-controlled pilot clinical trial. Six horses rece...
Block JA, Oegema TR, Sandy JD, Plaas A.Oral glucosamine (GlcN) has been widely studied for its potential therapeutic benefits in alleviating the pain and disability of osteoarthritis (OA). Its popularity has grown despite ongoing controversy regarding its effectiveness vs placebo in clinical trials, and lack of information regarding possible mechanisms of action. Here, we review the state of knowledge concerning the biology of GlcN as it relates to OA, and discuss a framework for future research directions. Methods: An editorial "narrative" review of peer-reviewed publications is organized into four topics (1) Chemistry and pharmac...
Hinchcliff KW, Morley PS, Guthrie AJ.To evaluate the efficacy of furosemide for prevention of exercise-induced pulmonary hemorrhage (EIPH) in Thoroughbred racehorses under typical racing conditions. Methods: Randomized, placebo-controlled, blinded, crossover field trial. Methods: 167 Thoroughbred racehorses. Methods: Horses were allocated to race fields of 9 to 16 horses each and raced twice, 1 week apart, with each of the 2 races consisting of the same race field and distance. Each horse received furosemide (500 mg, IV) before one race and a placebo (saline solution) before the other, with the order of treatments randomly determ...
Farag AMM, Ibrahim HMM.The current study was undertaken to investigate the effect of intravenous administration of ondansetron on the small and large intestinal motility in donkeys (Equus asinus) using non-invasive transabdominal ultrasonography. The current prospective, randomized, placebo-controlled, crossover study was conducted on thirty healthy donkeys (15 males and 15 females). The selected donkeys underwent two trials; the first was performed by intravenous administration of saline solution as a placebo, while the second was carried out by intravenous administration of ondansetron hydrochloride. The contracti...
Sturgill TL, Giguère S, Franklin RP, Cohen ND, Hagen J, Kalyuzhny AE.The objectives of the present study were to determine if administration of inactivated parapoxvirus ovis (IPPVO) can decrease the cumulative incidence of pneumonia and increase the number of IFN-γ- and IL-4-secreting cells among foals. Fifty-nine foals were randomly assigned to 2 treatment groups (IPPVO or placebo) prior to birth. At 24-48 h of age, foals received 2 ml of either IPPVO or a placebo by intramuscular injection. Injections were repeated 24h and 8 days later. The number of IFN-γ- and IL-4-secreting cells was measured using a validated ELISPOT assay on blood mononuclear cells coll...
van Loon JP, Menke ES, Doornenbal A, Back W, Hellebrekers LJ.The objective of this study was to evaluate the safety and efficacy of low dose lumbosacral epidural ropivacaine in ponies. Antinociceptive effects of epidural ropivacaine were evaluated by means of mechanical nociceptive thresholds (MNTs) at several spinal levels in conscious ponies. The effects of ropivacaine on nociceptive afferent transmission to the spinal cord were also assessed by measuring spinal cord somatosensory evoked potentials (SSEPs) in anaesthetised ponies. Ataxia scores were determined in conscious ponies to assess the effects on motor function. A randomised, placebo controlle...
Starzonek J, Roscher K, Blüher M, Blaue D, Schedlbauer C, Hirz M, Raila J, Vervuert I.In horses and ponies numerous medical conditions are known to be linked with inflammation in different tissues, especially in the liver. Besides affecting other metabolic pathways such as the expression of certain interleukins (IL), inflammation is associated with stress of the endoplasmic reticulum (ER). In particular, ER stress leads to adaptive stress response and can be measured by several markers of inflammatory and stress signalling pathways, like nuclear factor κB (NF-kB). Objective: To investigate lipopolysaccharide (LPS)-induced inflammatory reactions and their modulation in horses a...
Pascoe DR, Pascoe RR, Hughes JP, Stabenfeldt GH, Kindahl H.One hundred mares carrying twin conceptuses between gestation days (GD) 12 and 30 were assigned to 4 groups. Group-1 mares (n = 20) were given a placebo (sterile saline solution, IV, and sesame oil, IM). Group-2 mares (n = 32) were given a single dose of progesterone (625 mg, IM) in sesame oil. Group-3 mares (n = 28) were given multiple progesterone treatments (625 mg, IM) at 6-day intervals until GD 42. Group-4 mares (n = 20) were given a single treatment of flunixin meglumine (500 mg, IV) and progesterone (625 mg, IM). Each group was further assigned to equal subgroups A and B according to t...
Johnson LM, Holcombe SJ, Shearer TR, Watson V, Gandy J, Southwood LL, Lynch TM, Schroeder EL, Fogle CA, Sordillo LM.Identifying therapies that mitigate ischemic colonic injury and improve mucosal healing and intestinal viability are crucial to improving survival in horses with ≥360° large colon volvulus (LCV). Ethyl pyruvate is the ethyl ester of pyruvate with diverse pharmacologic effects that limit ischemic injury and hasten intestinal mucosal repair in preclinical rodents, sheep and swine models. The objective of this study was to determine the effects of ethyl pyruvate on systemic indices of colon viability, expression of inflammatory genes in whole blood, morbidity and survival after surgical correc...
Morresey PR, White GW, Poole HM, Hu T, Yin M, Sundman EA.OBJECTIVE To evaluate the effectiveness and safety of dipyrone to control pyrexia in horses with naturally occurring disease under field conditions. ANIMALS 138 horses with pyrexia and various infections evaluated at 14 veterinary sites in 12 states. PROCEDURES In the first (effectiveness) phase of this 2-phase study, horses were randomly assigned 3:1 to receive 1 dose of dipyrone (30 mg/kg [13.6 mg/lb], IV) or an equivalent amount of placebo. Effectiveness was defined as a decrease in rectal temperature ≥ 1.1°C (2°F), compared with the pretreatment value, or a rectal temperature of ≤ 38...
Jacquet-Guibon S, Dupays AG, Coudry V, Crevier-Denoix N, Leroy S, Siñeriz F, Chiappini F, Barritault D, Denoix JM.A randomized controlled trial was performed on racing horses, to evaluate the efficacy of a new class of therapeutic agents in regenerative medicine-ReGeneraTing Agents® (RGTA®), to treat tendinopathies. Preliminary uncontrolled studies on tendon healing in racing horses with RGTA® (OTR4131)-Equitend® showed encouraging results, justifying performing a randomized, controlled, multicenter study with a two-year racing performance follow up. The objective of this study was to evaluate the effect of Equitend® versus placebo on acute superficial digital flexor tendonitis in racing French Stand...
Johansson AM, Gardner SY, Levine JF, Papich MG, Lafevers DH, Goldman RB, Sheets MK, Atkins CE.Furosemide is the most common diuretic drug used in horses. Furosemide is routinely administered as IV or IM bolus doses 3-4 times a day. Administration PO is often suggested as an alternative, even though documentation of absorption and efficacy in horses is lacking. This study was carried out in a randomized, crossover design and compared 8-hour urine volume among control horses that received placebo, horses that received furosemide at 1 mg/kg PO, and horses that received furosemide at 1 mg/kg IV. Blood samples for analysis of plasma furosemide concentrations, PCV, and total solids were obta...
Hodge E, Kowalski A, Torcivia C, Lindborg S, Stefanovski D, Hart K, Frank N, van Eps A.The use of parallel dynamic tests to identify insulin dysregulation (ID) and pituitary pars intermedia dysfunction (PPID) in horses could have better diagnostic utility than measuring baseline hormone concentrations, if the tests do not alter diagnostic interpretation of one another. Objective: Performing a thyrotropin-releasing hormone (TRH) stimulation test before an oral sugar test (OST) would not affect results of OST. Methods: Twenty-six healthy university-owned horses. Methods: A prospective randomized placebo-controlled, crossover design was used to evaluate 3 OST protocols: OST alone, ...
Rothschild CM, Sellon DC, Bryan GM, Gay JM, Hines MT.The objectives of this study were to observe the effects of trimethoprim-sulfadiazine on equine tear production and to determine normal fluctuations in Schirmer tear test (STT) values in horses. A randomized, placebo-controlled, blinded clinical trial measuring STT values in 15 horses over an 8-week period was performed. The treatment group (eight horses) received 30 mg/kg trimethoprim-sulfadiazine orally once a day and the control group (seven horses) received placebo (flour) at the same time. All horses were housed outdoors throughout the study. Schirmer tear test values were measured at 0, ...
Huxford KE, Dart AJ, Perkins NR, Bell R, Jeffcott LB.AIMS To compare the efficacy of an enteric coated esomeprazole paste with an enteric coated omeprazole paste to increase gastric pH after oral administration in horses. METHODS Nine adult Standardbred horses were randomly assigned to three groups, each containing three horses, for a study comprising three phases of 10 days, with an 18-day washout period between each phase. In each phase, three horses received either 0.5 mg/kg esomeprazole, 1 mg/kg omeprazole or a placebo, as an oral paste, once daily for 10 days (Days 0-9). Over the course of study all horses received all three treatments....
Nieto JE, Aleman M, Anderson JD, Fiack C, Snyder JR.To assess gene expressions of cyclooxygenase-1 and -2 in oral, glandular gastric, and urinary bladder mucosae and determine the effect of oral administration of phenylbutazone on those gene expressions in horses. Methods: 12 healthy horses. Methods: Horses were allocated to receive phenylbutazone or placebo (6 horses/group); 1 placebo-treated horse with a cystic calculus was subsequently removed from the study, and those data were not analyzed. In each horse, the stomach and urinary bladder were evaluated for ulceration via endoscopy before and after experimental treatment. Oral, glandular gas...
Busechian S, Conti MB, Sgorbini M, Conte G, Marchesi MC, Pieramati C, Zappulla F, Vitale V, Rueca F.Equine gastric ulcer syndrome (EGUS) is the most common disease of the stomach in horses and treatment is based on the oral administration of omeprazole for at least 28 days. Aim of this study was to compare the efficacy of two formulations of oral omeprazole-powder paste and gastro-enteric resistant granules-in the treatment of naturally occurring gastric ulcers in racehorses. Thirty-two adult racehorses, aged between 2 and 10 years old, with clinical signs of EGUS were included in this blinded, randomized clinical trial. Two gastroscopies were performed to evaluate gastric lesions in the squ...
Beermann A, Clottu O, Reif M, Biegel U, Unger L, Koch C.Equine sarcoids (ES) are the most common cutaneous tumors in equids. Systemic treatment options are sparse. Subcutaneous (SC) injections of Viscum album extract (VAE) demonstrate efficacy as a systemic treatment directed against ES. Objective: To critically assess the therapeutic efficacy of orally administered VAE. Methods: Forty-five ES-affected, privately owned, 3-12 year-old horses. Methods: A 3-armed randomized placebo-controlled, double-blinded study was conducted in a double-dummy design. Horses were subjected to oral administration and SC injections of either VAE or placebo (VAE oral...
Scholl PJ, Chapman MR, French DD, Klei TR.In a trial designed to evaluate the efficacy of the recommended dosage of moxidectin 2% oral gel against the gastric stages of Gasterophilus spp., 14 ponies were selected from a herd on the basis of the inclusion criterion of the presence of Gasterophilus spp. eggs attached to their hair coats. After random allocation, the ponies were treated with 1 of 2 treatments, moxidectin 2% equine gel in a single dose at the commercial dosage of 400 microg moxidectin/kg body weight or placebo gel. The animals were necropsied 14 days posttreatment. Efficacies against second- and third-instar Gasterophilus...
The Journal of nutritionJune 4, 2002
Volume 132, Issue 6 Suppl 2 1628S-31S doi: 10.1093/jn/132.6.1628S
Williams CA, Hoffman RM, Kronfeld DS, Hess TM, Saker KE, Harris PA.alpha-Lipoic acid (LA) has demonstrated antioxidant effects in humans and laboratory animals. The objective of this study was to determine whether the effects of LA are similar in horses. Five Thoroughbred geldings were supplemented with 10 mg/kg/d DL-alpha-lipoic acid in a molasses and sweet feed carrier and five received only the carrier as a placebo (CON). Blood samples were obtained at baseline (0 d), after 7 and 14 d of supplementation, and 48 h postsupplementation (16 d). Blood fractions of red and white blood cells (RBC and WBC, respectively) and plasma were analyzed for glutathione (GS...
O'Banion MP, Sundman E, Edmonds M, Davis J.Dipyrone is a non-opioid, nonsteroidal anti-inflammatory drug with antipyretic and analgesic properties commonly used in horses. Dipyrone is rapidly hydrolyzed to the primary active metabolite 4-methylaminoantipyrine (4-MAA). The purpose of this study was to determine the pharmacokinetic profile of 4-MAA following repeated and escalating doses of intravenously administered dipyrone. Twenty-six horses were randomly allocated to five treatment groups (one placebo group and four dipyrone groups [30 mg/kg q8h, 30 mg/kg q12h, 60 mg/kg q8h, and 90 mg/kg q12h]) and treated for nine consecutive da...
Dai F, Costa ED, Giordano A, Heinzl EUL, Giongo P, Pagnozzi G, Cannas S, Minozzi G, Minero M.Horses preparation for competition may cause psychological and physical stress. Physical vascular therapy BEMER® is reported to increase vasomotion and microcirculation, supporting body healing. This study aimed at assessing whether BEMER® physical vascular therapy in horses influences recovery rate of hematological and biochemical blood parameters within 1 h after moderate exercise and reduces stress measured by physiological and behavioral indicators. This prospective, randomized, double blinded, placebo-controlled crossover study included twelve warmblood horses (3 mares, 8 geldings, 1 s...
Rohrbach BW, Sheerin PC, Cantrell CK, Matthews PM, Steiner JV, Dodds LE.To determine whether treatment with a preparation of Propionibacterium acnes would improve pregnancy and live foal rates in mares with persistent endometritis. Methods: Randomized placebo-controlled clinical trial. Methods: 95 mares with a cytologic diagnosis of persistent endometritis. Methods: Mares were treated with P acnes or placebo (both administered IV) on days 0, 2, and 6. No attempt was made to alter additional treatments administered by attending veterinarians. Information on breeding history, physical examination findings, results of cytologic examination and microbial culture of ut...
Schatzmann U, Gugelmann M, Von Cranach J, Ludwig BM, Rehm WF.Carprofen, flunixin meglumine and placebo in the form of a physiological solution of sodium chloride were tested in an open randomised cross-over trial for analgesic efficacy in horses with two external skin-stimulation systems. Both systems, the withers model and the "heating element" model, were compared in order to find an optimal way to measure pain perception after stimulating the skin with high temperature. No analgesic effect of flunixin or carprofen could be demonstrated when using the withers model. In the "heating element" model, a 1.1 mg/kg i.v. dose of flunixin meglumine failed to ...
Faghihi H, Rajaei SM, Mehrazin H, Golabdar S, Brooks DE.The aim of this study was to evaluate the effect of topical 1% tetracaine hydrochloride on the intraocular pressure (IOP) in ophthalmologically normal horses. Thirty eyes of 15 clinically normal horses were used for this study. The animals were randomly assigned to two groups (treatment and control). Prior to the instillation of 1% tetracaine or placebo, the baseline IOPs (T0) of each animal were recorded in both groups. Then one drop of tetracaine was instilled randomly into one eye of each horse in the treatment group (8 horses). In the control group (7 horses), one drop of artificial tear w...
Grady SE, Lescun TB, Moore GE, Cooper BR, Davern AJ, Brunner TJ, Taylor SD.The objective was to compare the analgesic efficacy of ketorolac tromethamine (KT) and two other nonsteroidal anti-inflammatory drugs (NSAIDs), including flunixin meglumine (FM) and phenylbutazone (PB), using a heart bar shoe (HBS) model of reversible foot lameness in horses. Nine adult horses were used in a blinded, randomized, placebo-controlled crossover study. After induction of left front limb lameness using a modified HBS model, one of three NSAIDs (KT, 2.0 mg/kg IV; FM, 1.1 mg/kg IV; PB, 4.4 mg/kg IV) or saline (placebo) was administered IV as a single dose. Lameness was assessed eve...
Wijekoon S, Tsogbadrakh M, Sunaga T, Wang Y, Mwale C, Kim S, Alimaa D, Okumura M.The aim of this study was to investigate the anti-hepcidin effect of pentosan polysulfate (PPS) in Mongolian horses. Twenty-six healthy horses were randomly allocated in to two-groups; one group was treated with a PPS once a week for 4-weeks while another group keeping as placebo. Blood samples at day 0 (D0), before race (BR; day 28) and after race (AR; day 28) were analyzed for serum biochemistry, hepcidin and iron concentrations. Significant reduction of hepcidin was observed at AR in PPS group when compared with BR placebo (P<0.05) and AR placebo (P<0.01). Mean hepcidin concentration differ...
Ural K, Ulutas B, Kar S.The purpose of this prospective, double-blinded, placebo-controlled clinical trial was to investigate the efficacy of topical eprinomectin for the treatment of psoroptic mange infestation in horses. 24 privately owned hunter/jumper and dressage horses were diagnosed with psoroptic mange infestation based on physical findings and skin scraping results were enrolled and randomly assigned to either topical eprinomectin pour-on solution (at a dose of 500microg/kg body weight weekly once for four applications) treatment group or a placebo group (purified water). Clinical evaluations and skin scrapi...
Bonneau S, Maynard L, Tomczuk K, Kok D, Eun HM.In this blinded randomized and controlled study, the anthelmintic efficacy of a tablet formula of ivermectin-praziquantel was evaluated in horses experimentally infected with three species of Strongylus larvae. Eighteen previously dewormed horses were inoculated on study day 0 with third-stage larvae of Strongylus vulgaris, Strongylus equinus, and Strongylus edentatus. The horses were randomly allocated to three groups (n = 6): test-drug (tablet formula), positive-control (reference gel), and negative-control (placebo tablet). On day 56, the horses were treated once with the respective drugs. ...
Craig JM, Lloyd DH, Roger D Jones CP.Clinical status and plasma phospholipid fatty acids of 33 horses with seasonal pruritus were investigated following fatty acid supplementation. Principal areas affected by pruritus were mane, tail, head and rump. There were no significant differences in clinical status between horses receiving test and placebo capsules. Horses receiving the test preparation showed significant reduction (weeks 0-12) in linoleic acid (P < 0.05) and significant increases (weeks 0-24) in dihomogammalinolenic acid and alpha linolenic acid (P < 0.05). Placebo-treated horses showed significant reductions (wee...
Milne DW, Gabel AA, Muir WW, Skarda RT, Hamlin RL, Pipers FS.In a double-blind study under simulated racing conditions, six Standardbred horses, which had been trained for 12 weeks, were given 1 mg of furosemide/kg of body weight or saline solution IV 15 minutes before the first of two warm-up workouts (1.6 km at 60-minute intervals). Sixty minutes later, 135 minutes after drug or placebo injection, these horses were driven 1.6 km at maximum speed. Heart rate, respiratory rate, cardiac output, pulmonary trunk pressure, body temperature, PCV, arterial oxygen, and plasma lactic acid were recorded during and after the first warm-up workout and after a simu...
Serrano-Rodríguez JM, Gómez-Díez M, Esgueva M, Castejón-Riber C, Mena-Bravo A, Priego-Capote F, Ayala N, Caballero JMS, Muñoz A.Pharmacokinetic and pharmacodynamic (PK/PD) properties of the angiotensin-converting enzyme inhibitor (ACEI) benazeprilat have not been evaluated in horses. This study was designed to establish PK profiles for benazepril and benazeprilat after intravenous (IV) and oral (PO) administration of benazepril using a PK/PD model. This study also aims to determine the effects of benazeprilat on serum angiotensin converting enzyme (ACE), selecting the most appropriate dose that suppresses ACE activity. Six healthy horses in a crossover design received IV benazepril at 0.50mg/kg and PO at doses 0 (place...
