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.
Whitfield-Cargile CM, Chung HC, Coleman MC, Cohen ND, Chamoun-Emanuelli AM, Ivanov I, Goldsby JS, Davidson LA, Gaynanova I, Ni Y, Chapkin RS.The equine gastrointestinal (GI) microbiome has been described in the context of various diseases. The observed changes, however, have not been linked to host function and therefore it remains unclear how specific changes in the microbiome alter cellular and molecular pathways within the GI tract. Further, non-invasive techniques to examine the host gene expression profile of the GI mucosa have been described in horses but not evaluated in response to interventions. Therefore, the objectives of our study were to (1) profile gene expression and metabolomic changes in an equine model of non-ster...
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...
Terpeluk ER, Schäfer J, Finkler-Schade C, Schuberth HJ.Feed supplements supporting animal welfare and performance are becoming increasingly important. Immunomodulatory effects of such products have been observed in many species. The aim of this study was to analyze whether food supplementation with a fermentation product (SCFP) affects the occurrence of foal diarrhea in early life, and whether the SCFP feeding has an impact on the immediate response to a parenteral vaccination at the age of 6-9 months. Eleven foals received the SCFP (OLI) and eleven foals were fed a placebo (PLA) for 29 days. Growth, diarrhea, and diarrhea severity were observed ...
Reed RA, Berghaus LJ, Reynolds RM, Holmes BT, Krikorian AM, Sakai DM, Ishikawa Y, Knych HK.Understanding the pharmacokinetics and pharmacodynamics of fentanyl in horses is crucial for optimizing pain management strategies in veterinary medicine. Unassigned: Six adult horses were enrolled in a randomized crossover design. Treatments included: placebo, two 100 mcg/h patches (LDF), four 100 mcg/h patches (MDF), and six 100 mcg/h patches (HDF). Patches were in place for 72 h. Blood was obtained for fentanyl plasma concentration determination, thermal threshold, mechanical threshold, heart rate, respiratory rate, and rectal temperature were obtained prior patch placement and at m...
Kemp KL, Skinner JE, Bertin FR.Phenylbutazone is often prescribed to manage pain caused by hyperinsulinemia-associated laminitis, but in diabetic people nonsteroidal anti-inflammatory drugs increase insulin secretion and pancreatic activity. Objective: Investigate the effect of phenylbutazone administration on insulin secretion in horses. It was hypothesized that phenylbutazone will increase insulin secretion in horses with insulin dysregulation (ID). Methods: Sixteen light breed horses, including 7 with ID. Methods: Randomized cross-over study design. Horses underwent an oral glucose test (OGT) after 9 days of treatment ...
Tavanaeimanesh H, Alinia Z, Sadeghian Chaleshtori S, Moosavian H, Mohebi Z, Daneshi M.During transportation many horses develop post-transportation infection, which can be life-threatening and end their sport career. Preventing mucus accumulation and inflammation during transportation is vital, emphasizing the need for effective strategies to enhance overall horse health welfare. Objective: Assess the impact of N-acetylcysteine (NAC) on mucus accumulation and inflammation in horses subjected to 18 hours of head confinement. Methods: Six healthy crossbred horses, 5.3 ± 2.1 years of age and weighing 387 ± 30 kg. Methods: Prospective placebo-controlled cross-over d...
Wood MK, Mason RM, Burk SV, Birmingham SSW.The goal of this study was to determine whether oral administration of α-casozepine (Zylkene) supplementation decreases the risk of disease in foals, as measured through salivary cortisol levels, temperature, clinical signs of disease, and body weight before and after weaning. Methods: 20 Thoroughbred foals were observed over 10 weeks, beginning 14 days prior to the time of weaning. Methods: Experimental foals were randomly selected and given α-casozepine daily for 10 weeks, while the controls received a placebo with the same frequency as the experimental group. The average daily height and ...
Pinnell EF, Hostnik LD, Watts MR, Timko KJ, Thriffiley AA, Stover MR, Koenig LE, Gorman OM, Toribio RE, Burns TA.5'-adenosine monophosphate-activated protein kinase (AMPK) agonists, particularly resveratrol (RES), have not been extensively evaluated for their effect on insulin dysregulation (ID) in horses. Objective: Evaluate the effects of treatment with RES (10 mg/kg PO q12h), metformin (MET; 30 mg/kg PO q12h), and aspirin (ASP; 20 mg/kg PO q24h) on experimentally induced ID. Methods: Thirty-three healthy, adult, light-breed horses. Methods: Unblinded, placebo-controlled, experimental trial evaluating effects of AMPK agonists (RES, MET, and ASP) on experimentally induced ID. Horses were randomly ...
Mallicote MF, Medina CI, Xie H, Zilberschtein J, Atria S, Manzie M, Hernandez JA, MacKay RJ.To assess the therapeutic efficacy of acupuncture in combination with Chinese herbs for treatment of horses affected with anhidrosis. Methods: 44 horses affected with anhidrosis for up to 3 years' duration were enrolled. Inclusion required both compatible clinical signs and results of a quantitative intradermal terbutaline sweat test. Methods: Study horses were randomly allocated into 2 groups. Group 1 (n = 19) was treated with daily Chinese herbs and 4 weekly acupuncture sessions. Group 2 (n = 25) was given daily hay powder as a placebo and 4 weekly sham acupuncture sessions. Horses were test...
Arias-Esquivel AM, Vasco ACCM, Lance J, Warren LK, Rodriguez-Campos LA, Lee MC, Rodriguez CN, Wickens CL.Cribbing, a stereotypic oral behavior observed in horses, involves placing incisors on a fixed object, arching the neck, pulling against the object, and emitting an audible grunt. This behavior has been associated with gastrointestinal (GI) dysfunction and gastric ulceration. In this randomized crossover study, we investigated the impact of a GI support supplement (SPL) on the GI environment and physiology of four cribbing (CB) and four non-cribbing horses (NCB). Mature Quarter Horses, acclimated to individual stalls for 16 hours daily with paddock turnout in pairs for 8 hours per day, were ra...
Watanabe T, Tahara K, Hirano E.Placental extract has been mostly used in skin care for cosmetic purposes. However, the use of various placental extracts has been limited due to the lack of established and effective application methods. Objective: In this study, we investigated the antiwrinkle effect of a cream formulation-LNC wrinkle eye cream (LNC-EC)-containing horse placental extract as the main ingredient. Methods: A total of 24 healthy women, aged 37-54 years, with wrinkle grades 1-3, were treated with LNC-EC for 2 weeks. The cream was applied on one-half of the participants' faces, and the results were compared with t...
Taylor SD, Hart KA, Vaughn S, Giancola SC, Serpa PBS, Santos AP.Ascorbic acid (AA) is an antioxidant that might be beneficial for adjunctive treatment of sepsis in horses. The optimal dose and effects on oxidative status are unknown. Objective: Ascorbic acid administration will increase plasma AA concentrations and decrease determinants of reactive oxygen metabolites (dROM), basal and stimulant-induced intraerythrocytic reactive oxygen species (ROS) concentrations, and stimulant-induced neutrophil ROS production, and increase plasma antioxidant capacity (PAC) in a dose-dependent manner. Methods: Eight healthy horses. Methods: Randomized placebo-controlled ...
Brys M, Claerebout E, Chiers K.The aim of this prospective, randomized, single-blinded, and placebo-controlled clinical trial was to investigate the efficacy of a moxidectin pour-on solution for the treatment of Chorioptes bovis infestation in Belgian draft horses, and in addition, to evaluate the effect of this treatment on the clinical signs and lesions associated with chronic progressive lymphedema (CPL). Nineteen privately owned Belgian draft horses were randomly assigned to either a treatment group (moxidectin pour-on formulation, n = 10) or a placebo group (phosphate-buffered saline (PBS), n = 9). On Day 0, all 19...
Testicular degeneration (TD) is the most frequent cause of sub or infertility in stallions. Currently, mesenchymal stem cells (MSC) have been studied as a therapeutic option for several diseases including induced-TD in laboratory animals. Therefore, this study aimed to evaluate the effect of intratesticular MSC therapy on the testicular histology of stallions submitted to scrotal heat stress. Ten healthy Miniature-horse stallions were submitted to testicular heat stress induced by a heating wrap device (42-45°C). Afterward, the stallions were divided into two groups and treated seven days lat...
Lindåse S, Nostell K, Forslund A, Bergsten P, Bröjer J.Decreasing hyperinsulinemia is crucial in preventing laminitis in insulin dysregulated (ID) horses. Complementary pharmacological treatments that efficiently decrease postprandial hyperinsulinemia in ID horses are needed. Objective: Compare short-term effects of canagliflozin vs placebo on glucose and insulin responses to an oral sugar test (OST) as well as the effects on body weight and triglyceride concentrations in horses with ID. Methods: Sixteen privately-owned ID horses. Methods: A single-center, randomized, double-blind, placebo-controlled, parallel design study. The horses were randomi...
Carlier S, Depuydt E, Suls M, Bocqué C, Thys J, Vandenberghe A, Martens A, Saunders J, Hellmann K, Braun G, Beerts C, Spaas JH.Mesenchymal stem cells are an innovative therapeutic for various equine orthopaedic diseases, including soft tissue injuries. Objective: To evaluate the safety and efficacy of tenogenic primed equine allogeneic peripheral blood-derived mesenchymal stem cells (tpMSCs) in horses with naturally occurring superficial digital flexor tendon (SDFT) and suspensory ligament (SL) injuries. Methods: Multicentre, blinded, randomised, placebo-controlled clinical trial. Methods: One hundred client-owned horses with SDFT and SL injuries were randomised to receive an intralesional tpMSC (66) or saline (34) in...
Alshut F, Venner M, Martinsson G, Vervuert I.Electrolyte supplementation may be a risk factor for gastric mucosal lesions, but relevant evidence is limited in horses. Objective: Investigate the effects of PO sodium chloride (NaCl) supplementation on the gastric mucosa of exercising horses. We hypothesized that NaCl supplementation would neither cause nor exacerbate existing gastric mucosal damage. Methods: Fifteen 3-year-old healthy Warmblood stallions from a stud farm. Methods: Placebo-controlled study with a crossover design. Horses were fed either a NaCl pellet at a dosage adequate to replace the electrolyte losses in 10 L sweat or ...
O'Brien M, Mochel JP, Kersh K, Wang C, Troy J.Pain management is critical to equine welfare with non-steroidal anti-inflammatory drugs (NSAID) commonly used in horses. However, systemic NSAID use is limited by harmful gastrointestinal and renal side effects. Intravenous regional limb perfusion (IVRLP) is a technique used in horses that produces high, local antibiotic concentrations while limiting systemic circulation. NSAID-IVRLP would be a novel method of local pain management while limiting systemic NSAID side effects. To date, NSAID-IVRLP administration has not been reported in horses. This study aimed to identify the pharmacokinetics ...
Hobbs K, Luethy D, Davis J, Mallicote M, Torcivia C, Kulp J, Stefanovski D, Futterman C, Cooper F, van Eps A.Trazodone, a serotonin receptor antagonist and reuptake inhibitor, might be a useful adjunctive treatment in the initial management of horses with acute laminitis if it minimizes ambulation or encourages recumbency. Objective: (1) Evaluate the effects of PO trazodone on ambulatory activity and recumbency in healthy horses; and (2) assess the pharmacokinetics of multiple PO doses of trazodone. Methods: In a randomized cross-over design, 8 healthy horses received placebo or trazodone at 2 doses (2.5 and 7.5 mg/kg) PO q12h for 48 hours with a 14-day washout period between treatments. Forelimb...
Marshall K, Marsella R.Increased antimicrobial resistance highlights the need for alternatives to antibiotics. Bacteriophages, which are benign viruses that kill bacteria, are promising. We studied the efficacy of topical bacteriophages for treating equine staphylococcal superficial pyodermas. Eight isolates were tested against a bacteriophage bank, and a cocktail consisting of two bacteriophages was prepared. Twenty horses with clinical and cytological evidence of superficial pyoderma and confirmed infection based on swabbed culture were enrolled in the study. Each horse received both the bacteriophage cocktail a...
Punzón E, García-Castillo M, Rico MA, Padilla L, Pradera A.Mesenchymal stem cells are multipotent cells with a wide range of therapeutic applications, including, among others, tissue regeneration. This work aims to test the safety (EUC-MSC) of intra-articular administration of equine umbilical cord mesenchymal stem cells in young healthy dogs under field conditions following single and repeated administration. This was compared with the safety profile of allogenic canine adipose derived mesenchymal stem cells (CAD-MSC) and placebo in order to define the safety of xenogeneic use of mesenchymal stem cells when administered intra-articular. Twenty-four p...
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...
Mercer MA, Davis JL, McKenzie HC, Messenger KM, Schaefer E, Council-Troche RM, Werre SR.Acetaminophen has been evaluated in horses for treatment of musculoskeletal pain but not as an antipyretic. Objective: To determine the pharmacokinetics and efficacy of acetaminophen compared to placebo and flunixin meglumine in adult horses with experimentally induced endotoxemia. Methods: Eight university owned research horses with experimentally induced endotoxemia. Methods: Randomized placebo controlled crossover study. Horses were treated with acetaminophen (30 mg/kg PO; APAP), flunixin meglumine (1.1 mg/kg, PO; FLU), and placebo (PO; PLAC) 2 hours after administration of LPS. Plasma ...
Urayama S, Tanaka A, Kusano K, Sato H, Muranaka M, Mita H, Nagashima T, Matsuda H.Flunixin meglumine (FM), a nonselective cyclooxygenase (COX) inhibitor, is most frequently selected for the treatment of equine systemic inflammatory response syndrome (SIRS)/endotoxemia. However, FM has considerable adverse effects on gastrointestinal function. The aims of this study were to compare the effect of meloxicam (MX), a COX-2 selective inhibitor commonly used in equine clinical practice, with FM, and to investigate the potential for clinical application in horses with SIRS/endotoxemia. Fifteen horses were divided into three groups of five and orally administered MX (0.6 mg/kg), FM ...
Repac J, Mangan E, Xie H.Acupuncture is an inexpensive nonpharmacological modality that has a variety of musculoskeletal, neurologic, and internal medicine applications for the equine practitioner. Common uses include back pain colic, laminitis, laryngeal hemiplegia, and suprascapular neuropathy. Although there is a growing body of literature supporting the use of acupuncture in equids, there remains a need for further robust, double-blinded, placebo-controlled clinical efficacy trials.
Hoeberg E, Haga HA, Lervik A.To investigate whether morphine causes a change in mean arterial blood pressure (MAP) heart rate (HR) and oxygen extraction (OE) rate in healthy horses anesthetized with isoflurane and a dexmedetomidine infusion. Unassigned: The study design was prospective clinical, randomized, blinded two groups including 33 horses. All horses were sedated with romifidine IV, and anesthesia was induced with midazolam IV and ketamine IV and maintained with isoflurane in oxygen and medical air and a dexmedetomidine infusion. As a baseline venous and arterial blood, HR and MAP were sampled. Thereafter either mo...
Rhiner T, Fettelschoss V, Schoster A, Birkmann K, Fettelschoss-Gabriel A.Previously, virus-like particle (VLP)-based self-vaccinations targeting interleukin (IL)-5 or IL-31 have been suggested to treat equine insect bite hypersensitivity (IBH), a seasonal recurrent allergic dermatitis in horses. The IL-5-targeting equine vaccine significantly reduced blood eosinophil counts in horses, similar to human monoclonal antibodies targeting IL-5 or the IL-5 receptor alpha (IL-5Rα). Previous studies in humans have also reported an additional effect on reduction of basophil counts. The aim of the present study was to evaluate whether an equine anti-IL-5 vaccine affected blo...
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...
Taylor SD, Serpa PBS, Santos AP, Hart KA, Vaughn SA, Moore GE, Mukhopadhyay A, Page AE.A systemic and dysregulated immune response to infection contributes to morbidity and mortality associated with sepsis. Peripheral blood-derived mesenchymal stromal cells (PB-MSC) mitigate inflammation in animal models of sepsis. Allogeneic PB-MSC administered IV to horses is well-tolerated but therapeutic benefits are unknown. Objective: After IV lipopolysaccharide (LPS) infusion, horses treated with PB-MSC would have less severe clinical signs, clinicopathological abnormalities, inflammatory cytokine gene expression, and oxidative stress compared to controls administered a placebo. Methods: ...
Lucassen A, Hankel J, Finkler-Schade C, Osbelt L, Strowig T, Visscher C, Schuberth HJ.Feed supplements such as fermentation products (SCFP) alter immune responses in horses. The purpose of this study was to analyze whether a prebiotic activity of the SCFP alters the gut microbiome in horses. Racehorses were fed either SCFP (Olimond BB, OLI, = 6) or placebo pellets (PLA, = 5) for 43 days. Fecal microbiota analysis was performed using 16S rRNA gene sequencing. The numbers and function of circulating immune cell subpopulations were analyzed by flow cytometry. SCFP supplementation resulted in non-consistent differences in fecal microbiota between the PLA and OLI during the feedi...
Watts AE, Millar NL, Platt J, Kitson SM, Akbar M, Rech R, Griffin J, Pool R, Hughes T, McInnes IB, Gilchrist DS.Tendon injuries (tendinopathies) are common in human and equine athletes and characterized by dysregulated collagen matrix, resulting in tendon damage. We have previously demonstrated a functional role for microRNA29a (miR29a) as a post-transcriptional regulator of collagen 3 expression in murine and human tendon injury. Given the translational potential, we designed a randomized, blinded trial to evaluate the potential of a miR29a replacement therapy as a therapeutic option to treat tendinopathy in an equine model that closely mimics human disease. Tendon injury was induced in the superficial...
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...
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...
Venner M, Astheimer K, Lämmer M, Giguère S.Mass antimicrobial treatment of foals with small subclinical ultrasonographic pulmonary lesions is empirical practice on many farms with endemic disease caused by Rhodococcus equi. Objective: Mass antimicrobial treatment of foals with subclinical ultrasonographic pulmonary lesions is unnecessary. Methods: One hundred and eight foals on a farm endemic for infections caused by R. equi. Methods: Controlled, randomized, and double-blinded prospective study. Foals with ultrasonographic evidence of pulmonary abscesses 5.0-10 cm in diameter (n = 108) were randomly allocated in 5 treatment groups: (1)...
Broeckx SY, Martens AM, Bertone AL, Van Brantegem L, Duchateau L, Van Hecke L, Dumoulin M, Oosterlinck M, Chiers K, Hussein H, Pille F, Spaas JH.There is a need to improve therapies for osteoarthritis in horses. Objective: To assess the efficacy of equine allogeneic chondrogenic-induced mesenchymal stem cells combined with equine allogeneic plasma as a novel therapy for osteoarthritis in horses. Methods: Randomised, double-blinded, placebo-controlled experiment. Methods: In 12 healthy horses, osteoarthritis was induced in the metacarpophalangeal joint using an osteochondral fragment-groove model. Five weeks after surgery, horses were randomly assigned to either an intra-articular injection with chondrogenic-induced mesenchymal stem cel...
Frisbie DD, Kawcak CE, McIlwraith CW.OBJECTIVE-To assess the clinical, biochemical, and histologic effects of extracorporeal shock wave therapy (ESWT) in the treatment of horses with experimentally induced osteoarthritis (OA). ANIMALS-Twenty-four 2- to 3-year-old horses without evidence of lameness. PROCEDURES-OA was induced arthroscopically in 1 middle carpal joint of each horse. Fourteen days after induction of OA, horses were treated with a sham ESWT probe (placebo; n = 8), polysulfated glycosaminoglycan (PSGAG) administered IM every 4 days for 28 days as a positive control treatment (8), or ESWT administered on days 14 and 28...
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...
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...
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...
Giguère S.Pneumonia caused by Rhodococcus equi remains an important cause of disease and death in foals. The combination of a macrolide (erythromycin, azithromycin, or clarithromycin) with rifampin remains the recommended therapy for foals with clinical signs of infection caused by R equi. Most foals with small, subclinical ultrasonographic pulmonary lesions associated with R equi recover without therapy, and administration of antimicrobial agents to these subclinically affected foals does not hasten lesion resolution relative to administration of a placebo. Resistance to macrolides and rifampin in isol...
Lavoie JP, Bullone M, Rodrigues N, Germim P, Albrecht B, von Salis-Soglio M.Inhaled corticosteroids are effective for the treatment of equine asthma but they induce cortisol suppression with potential side effects. Objective: To study the efficacy of ciclesonide, an inhaled corticosteroid with an improved safety profile, on lung function, clinical signs related to airway obstruction, and serum cortisol levels in asthmatic horses exposed to a mouldy hay challenge. Methods: Cross-over placebo controlled, blinded, randomised experiment. Methods: Sixteen horses were enrolled in three subsequent dose-titration studies (8 horses/study) to investigate the effects of inhaled ...
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 ...
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 ...
Raekallio M, Taylor PM, Bennett RC.Twenty-five horses undergoing arthroscopic surgery were studied to develop a scheme for assessing pain in horses while investigating the effects of phenylbutazone (PBZ) analgesia. Fifteen of the 25 horses received PBZ 4 mg/kg intravenously (IV) before surgery and 2 mg/kg (IV) every 12 hours thereafter until 60 hours; the remaining 10 (placebo group) were given a corresponding volume of saline. In both groups, venous blood samples were collected for catecholamine, beta-endorphin, and cortisol assays before premedication and up to 72 hours after surgery. Postoperative pain was evaluated by measu...
Yamazaki M, Kusano K, Ishibashi T, Kiuchi M, Koyama K.Upon intensive, exhaustive exercise, exercise-induced reactive oxygen species may exceed the antioxidant defence threshold, consequently resulting in muscular damage or late-onset chronic inflammation. Recently, the therapeutic antioxidant and anti-inflammatory effects of molecular hydrogen (H2) for human rheumatoid arthritis have been demonstrated. However, it is also important to clarify the effects of administrating H2 in large animals other than humans, as H2 is thought to reach the target organ by passive diffusion upon delivery from the blood flow, indicating that the distance from the a...
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...
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...
Schoster A, Guardabassi L, Staempfli HR, Abrahams M, Jalali M, Weese JS.The microbiota plays a key role in health and disease. Probiotics are a potential way to therapeutically modify the intestinal microbiota and prevent disease. Objective: The aim of this study was to investigate the effects of probiotics on the bacterial microbiota of foals during and after administration. Methods: Randomised placebo controlled field trial. Methods: Thirty-eight healthy neonatal foals enrolled in a previous study were selected. The foals had received a multi-strain probiotic (four Lactobacillus spp. 3-4 × 10 colony-forming units (cfu)/g each, Bifidobacterium animalis spp. lact...
Klier J, Lehmann B, Fuchs S, Reese S, Hirschmann A, Coester C, Winter G, Gehlen H.Recurrent airway obstruction (RAO), an asthma-like disease, is 1 of the most common allergic diseases in horses in the northern hemisphere. Hypersensitivity reactions to environmental antigens cause an allergic inflammatory response in the equine airways. Cytosine-phosphate-guanosine-oligodeoxynucleotides (CpG-ODN) are known to direct the immune system toward a Th1-pathway, and away from the pro-allergic Th2-line (Th2/Th1-shift). Gelatin nanoparticles (GNPs) are biocompatible and biodegradable immunological inert drug delivery systems that protect CpG-ODN against nuclease degeneration. Prelimi...
Vardy MD, Gardner TR, Cosman F, Scotti RJ, Mikhail MS, Preiss-Bloom AO, Williams JK, Cline JM, Lindsay R.The purpose of this study was to determine effects of ovariectomy (OVX) and conjugated equine estrogens plus medroxyprogesterone acetate (CEE/MPA), or ethinyl estradiol plus norethindrone acetate (EE/NA) on biomechanics of uterosacral (USL) and round (RL) ligaments in postmenopausal (PMP) monkeys. Methods: This was a randomized, triple blind, placebo-controlled study. OVX monkeys received 12 months no treatment (Pbo) (n = 19), CEE/MPA (n = 19), or EE/NA (n = 21). USL and RL step strains and stress-relaxation data were curve-fitted, giving strain-dependent tensile modulus (TM) from 0% to 30%. R...
Ziebell KL, Steinmann H, Kretzdorn D, Schlapp T, Failing K, Schmeer N.The efficacy of an immunomodulator, Baypamun N, was tested in 4-10-month-old horses which were exposed to stress by weaning, transport and commingling with yearlings from different breeders (crowding). Verum (n = 26) and placebo animals (n = 27) received three intramuscular injections of the investigational preparations (days 0, 2, 9) starting at the day of commingling in one stable. The incidence of acute respiratory disease was high during the first 4 weeks after commingling. Approximately 50% of all horses showed seroconversion due to field infection by EHV1 and EHV4 during the observation ...
Venner M, Credner N, Lämmer M, Giguère S.The objectives of the present study were to determine the relative efficacy of tulathromycin, azithromycin, or azithromycin with rifampin for the treatment of pulmonary abscesses on a farm with endemic infections caused by Rhodococcus equi. Foals with ultrasonographic evidence of pulmonary abscesses (abscess score 8.0-15 cm; n=120) were randomly allocated in four equal treatment groups: (1) tulathromycin intramuscularly; (2) azithromycin monotherapy, orally; (3) azithromycin with rifampin, orally; (4) saline intramuscularly as a placebo. Physical examination and thoracic ultrasonography were p...
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...
John J, Roediger K, Schroedl W, Aldaher N, Vervuert I.Almost all foals develop transient diarrhoea within the first weeks of life. Studies indicated different viral, bacterial, and parasitic causes, such as rotavirus, Clostridium perfringens, Escherichia coli, and Cryptosporidium are discussed. But little is known about the development of intestinal microflora in foals. The present study investigated whether the supplementation with Bacillus cereus var. toyoi would modify the developing intestinal microflora and consequently reduce diarrhoea in foals. From birth, the foals were randomly assigned to three treatment groups: placebo (10 mL isotonic...
Pedersen SK, Cribb AE, Read EK, French D, Banse HE.In equids, phenylbutazone at high doses induces gastric disease, primarily in the glandular portion of the stomach. However, the mechanism of nonsteroidal anti-inflammatory drug (NSAID)-induced gastric disease in horses has yet to be determined. While phenylbutazone-associated ulceration is often attributed to a decrease in basal gastric prostaglandins, this has not been demonstrated in the horse. Twelve horses were randomly assigned to treatment (n = 6; 4.4 mg/kg phenylbutazone PO in 20 ml molasses q 12 hr for 7 days) or placebo (n = 6; 20 ml molasses PO q 12 hr for 7 days) groups....
Foreman JH, Barange A, Lawrence LM, Hungerford LL.The objective was to test the hypothesis that phenylbutazone (PBZ) alleviates lameness in an adjustable heart bar shoe model of equine foot pain. Eight Quarter Horse mares underwent 4-weekly treatments randomly: 0.9% saline placebo (SAL: 1 mL/45 kg body weight i.v.) with no lameness; SAL with lameness; PBZ (4.4 mg/kg body weight i.v.) with no lameness; and PBZ with lameness. Blinded heart rate (HR) and lameness score (LS) were assessed every 20 min for 2 h and then hourly through 9 h. At 1 h SAL or PBZ was administered. Jugular venous samples were obtained at hours 0, 1, 2, 4, 6, and 8 and wer...
DePuy T, Howard R, Keegan K, Wilson D, Kramer J, Cook JL, Childers MK.To test the hypothesis that botulinum toxin type A (BoNT-A) can attenuate lameness associated with acute synovitis in an equine model. Methods: Four horses 2-6 yrs of age with clinically normal carpi were studied for 15 days. Kinematic gait analysis and clinical measures of lameness were conducted before and after experimental interventions. Horses were randomly assigned to either placebo (saline) or treatment (BoNT-A) groups. On day 0 of the intervention, 50 units of BoNT-A or an equivalent volume of saline (0.09%) was given into the middle carpal joints. On day 14, acute synovitis was induce...
Ashrafi GH, Piuko K, Burden F, Yuan Z, Gault EA, Müller M, Trawford A, Reid SWJ, Nasir L, Campo MS.Equine sarcoids are fibroblastic skin tumours affecting equids worldwide. While the pathogenesis is not entirely understood, infection with bovine papillomavirus (BPV) type 1 (and less commonly type 2) has been implicated as a major factor in the disease process. Sarcoids very seldom regress and in fact often recrudesce following therapy. Nothing is known about the immune response of the equine host to BPV. Given that the viral genes are expressed in sarcoids, it is reasonable to assume that vaccination of animals against the expressed viral proteins would lead to the induction of an immune re...
Rush BR, Raub ES, Thomsen MM, Davis EG, Matson CJ, Hakala JE.To evaluate clinical response, pulmonary function, and adrenal gland response to incremental doses of beclomethasone dipropionate in horses with recurrent airway obstruction. Methods: Crossover trial. Methods: 8 horses with recurrent airway obstruction. Methods: Horses randomly assigned to 4 groups were treated twice daily via aerosol administration of placebo or 500, 1,000, or 1,500 micrograms of beclomethasone dipropionate in a crossover design with a 10-day minimum washout period. Subjective assessment of airway obstruction, serum cortisol concentration, and maximum change in pleural pressu...
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...
