Disease treatment in horses encompasses a range of medical interventions and management strategies aimed at addressing various health conditions affecting equine species. These treatments can include pharmacological approaches, such as the administration of antibiotics, anti-inflammatory drugs, and antiparasitic medications, as well as non-pharmacological methods like physical therapy, dietary adjustments, and surgical procedures. The selection of appropriate treatments depends on the specific disease, its severity, and the individual needs of the horse. This topic brings together peer-reviewed research studies and scholarly articles that explore the efficacy, safety, and advancements in therapeutic options for equine diseases, providing insights into best practices and emerging trends in equine veterinary medicine.
Rothschild CM, Hines MT, Breuhaus B, Gay J, Sellon DC.Trimethoprim-sulfadiazine was administered to horses in a randomized, placebo controlled study to determine the effects of potentiated sulfonamides on thyroid function in normal horses. The treatment group included eight horses that received trimethoprim-sulfadiazine mixed with molasses orally at 30 mg/kg once daily for eight weeks. The control group included 8 horses that received an oral placebo (flour mixed with molasses) once daily for the same period. Thyroid function was evaluated prior to initiation of treatment and after 8 weeks of treatment. Serum concentrations of total and free trii...
Lehner AF, Hughes CG, Harkins JD, Nickerson C, Mollett B, Dirikolu L, Bosken J, Camargo F, Boyles J, Troppmann A, Karpiesiuk WW, Woods WE, Tobin T.We have investigated the detection, confirmation, and metabolism of the beta-adrenergic agonist ractopamine administered as Paylean to the horse. A Testing Components Corporation enzyme-linked imunosorbent assay (ELISA) kit for ractopamine displayed linear response between 1.0 and 100 ng/mL with an I-50 of 10 ng/mL and an effective screening limit of detection of 50 ng/mL. The kit was readily able to detect ractopamine equivalents in unhydrolyzed urine up to 24 h following a 300-mg oral dose. Gas chromatography-mass spectrometry (GC-MS) confirmation comprised glucuronidase treatment, solid-pha...
Wijnberg ID, Ververs FF.Five adult horses with ventricular extra systoles (VES) and 2 with ventricular tachycardia (VT) refractory to treatment with rest, anti-inflammatory drugs, lidocaine, or procainamide were treated with phenytoin sodium p.o. q12h. The starting dosage of phenytoin was 20 or 22 mg/kg body weight (BW) q12h, and the maintenance dosage varied from 8 to 17 mg/kg BW q12h. The mean +/- standard deviation therapeutic blood concentration of total phenytoin was 8.8 +/- 2.1 mg/L, and the mean concentration of free phenytoin of 2.5 +/- 0.5 mg/L was relatively constant at a range of 24 to 29% of the total phe...
Slocombe JO.Aims of this study with 13 equids naturally infected with Anoplocephala perfoliata were to document (i) a critical test with a period of 48 h from treatment to necropsy to assess the efficacy of an anthelmintic against the tapeworm, (ii) the efficacy of pyrantel pamoate oral paste at 13.2 mg pyrantel base/kg body weight, and (iii) the time after treatment when fecal egg counts would best estimate the tapeworm's prevalence in a herd. Feces passed in successive 12-h periods after treatment were examined for tapeworms. At necropsy, tapeworms in equids were identified as attached to the mucosa or ...
Pellegrini-Masini A, Poppenga RH, Sweeney RW.An injectable preparation of flunixin meglumine was administered orally and intravenously at a dose of 1.1 mg/kg to six healthy adult horses in a cross-over design. Flunixin meglumine was detected in plasma within 15 min of administration and peak plasma concentrations were observed 45-60 min after oral administration. Mean bioavailability of the oral drug was 71.9 +/- 26.0%, with an absorption half-life of 0.76 h. The apparent elimination half-life after oral administration was 2.4 h. The injectable preparation of flunixin meglumine is suitable for oral administration to horses.
Lescun TB, Morisset SM, Fugaro MN, Blevins WE.A 3-month-old Quarter Horse colt sustained a penetrating injury over the coronary band on the right forelimb resulting in an articular bone sequestrum and septic arthritis of the distal interphalangeal joint. Despite aggressive treatment for septic arthritis, severe osteoarthritis and ongoing sepsis resulted in persistent lameness. Facilitated ankylosis of the distal interphalangeal joint was performed using a combination of open surgical debridement, placement of an autogenous cancellous bone graft and stabilisation within a transfixation cast. Bony ankylosis of the joint was observed radiogr...
Weese JS, Anderson ME, Lowe A, Penno R, da Costa TM, Button L, Goth KC.Probiotics have not been demonstrated to provide any beneficial health effects in horses, possibly because of improper selection of probiotic organisms. This study was designed to identify lactic acid bacteria of equine origin with predetermined beneficial properties which might make them useful as therapeutic probiotics. Objective: A small percentage of lactic acid bacteria that are native to the intestinal tract of horses possess properties that may be useful in the treatment and/or prevention of gastrointestinal disease in horses. Methods: Faecal samples were collected from healthy mature h...
Story MR, Bramlage LR.Historically, there has been a consensus that conservative management of subchondral cystic lesions of the distal phalanx carries a poor prognosis. Surgical management has been advocated; however, there are no reports documenting its routine use and successful surgical treatment. Objective: To describe arthroscopically-guided curettage of distal phalangeal subchondral cystic lesions (SCLs) and report the qualitative and quantitative results in 11 affected horses age 16-33 months. Methods: Medical records of horses with previously treated lameness resulting from SCLs of the third phalanx were r...
Crowe OM, Dyson SJ, Wright IM, Schramme MC, Smith RK.Proximal suspensory desmitis (PSD) is diagnosed with increasing frequency in horses and radial pressure wave therapy (RPWT) is a widely used therapy for painful orthopaedic conditions in man and dogs. There are, however, few published data as to the outcome of its use in PSD. Objective: To evaluate the use of RPWT in the treatment of chronic or recurrent PSD in the horse, an injury which carries a poor prognosis for return to athletic function with conservative management alone. Objective: RPWT and controlled exercise improves the prognosis of chronic or recurrent PSD in the horse when compare...
Engeli E, Haussler KK, Erb HN.Sacroiliac joint osteoarthritis has been recognised as a significant cause of poor performance in competition and racehorses. Reliable diagnostic tools are currently lacking. The diagnosis has been based typically on exclusion of other possible causes of poor performance, back pain and hindlimb lameness. Objective: To develop a safe, reliable and minimally invasive periarticular or intra-articular injection technique of potential use for diagnosis and therapy of sacroiliac joint disease in horses. Methods: Twenty-six horses were used to develop and assess a medial approach to the sacroiliac jo...
Shoemaker R, Bailey J, Janzen E, Wilson DG.Castration is one of the most common routine surgical procedures performed in the horse, from which a number of potential complications can arise. We undertook a prospective evaluation of short-term complications associated with castration of draught colts over a 3-year period (1998-2000). Objective: To compare castration complications in a large number of draught foals with previously published literature. Methods: Five hundred and sixty-eight draught colts, age 4 or 5 months, were castrated in field conditions. Foals were observed for complications for 24 h post operatively. Results: There w...
van der Velden MA, van der Harst MR.A literature review is given concerning the occurrence, clinical signs and possible treatment of the different types of inguinal herniation in foals. A six-week old filly with a reducible inguinal hernia is described in detail.
Lepage OM, Perron MF, Cadoré JL.Advances in the understanding of guttural pouch physiology and novel therapeutic approaches to mycotic infections in the horse are reviewed. It is suggested that the guttural pouches may contribute to the regulation of arterial blood temperature, cooling the circulation to the brain to below body temperature. Aspergillus spp. is the major organism found in a guttural pouch affected with mycosis but it is unclear why this agent becomes aggressive. Conventional therapy aims to prevent fatal haemorrhage and to treat any neurological lesions but it is desirable to try to prevent the disease. A tec...
Deprez P, Vercruysse J.The results of the treatment with moxidectin or ivermectin of 20 horses with clinical cyathostominosis were studied during a 3-week observation period. Both treatments were effective in completely eliminating larvae from the faeces within 1 or 2 weeks, but no significant improvement in body weight or clinical parameters could be demonstrated over the observation period. The poor short time results of the treatment support the need for an adequate prevention of cyathostominosis in horses.
Flock M, Jacobsson K, Frykberg L, Hirst TR, Franklin A, Guss B, Flock JI.Horses that have undergone infection caused by Streptococcus equi subspecies equi (strangles) were found to have significantly increased serum antibody titers against three previously characterized proteins, FNZ (cell surface-bound fibronectin binding protein), SFS (secreted fibronectin binding protein), and EAG (alpha2-macroglobulin, albumin, and immunoglobulin G [IgG] binding protein) from S. equi. To assess the protective efficacy of vaccination with these three proteins, a mouse model of equine strangles was utilized. Parts of the three recombinant proteins were used to immunize mice, eith...
Alexander GR, Chester Z.To assess the effectiveness of free conjunctival grafts in the treatment of horses with a range of keratopathies. Methods: A retrospective clinical study of ten client-owned horses treated at Murdoch University Veterinary Hospital from May 1996 to September 2001. Methods: The suitability of patients for the surgical procedure was assessed using a slit lamp biomicroscope and by direct and indirect ophthalmoscopy. Surgery was performed with the aid of an operating microscope, under general anaesthesia. A subpalpebral ocular lavage catheter was used for administration of topical atropine and anti...
Marsh AE, Lakritz J, Johnson PJ, Miller MA, Chiang YW, Chu HJ.Clinically normal horses developed cellular immunity to Sarcocystis neurona following IM vaccination with a commercial killed S. neurona vaccine, as indicated by the development of measurable anti-S. neurona IgG antibodies and additional intradermal skin testing. Large-scale independent assessments of the vaccine's performance and safety are in progress under field conditions. The next step in the evaluation of this vaccine would be to attempt experimental challenge after a reproducible reliable equine model of S. neurona encephalitis has been established that allows for reisolation of the pat...
French KR, Pollitt CC.The key lesion of laminitis is separation at the hoof lamellar dermal-epidermal interface. For this to happen the structural and adhesion proteins of the basement membrane zone must be altered. Which proteins and how damage to them leads to the lamellar separation of laminitis is unknown. Objective: To investigate lamellar hemidesmosome and cytoskeleton damage and basement membrane dysadhesion using light microscopy (LM) and immunofluorescence microscopy (IFM). Methods: Cryostat sections of lamellar tissues from 2 control and 6 Standardbred horses with oligofructose induced laminitis were stud...
French KR, Pollitt CC.Light microscopical studies show that the key lesion of laminitis is separation at the hoof lamellar dermal-epidermal interface. More precise knowledge of the damage occurring in the lamellar basement membrane zone may result if laminitis affected tissue is examined with the transmission electron microscope. This could lead to better understanding of the pathogenesis of lesions and the means of treatment or prevention. Objective: To investigate the ultrastructure of acute laminitis as disease of greater severity is induced by increasing oligofructose (OF) dosage. Methods: Three pairs of normal...
Kyaw-Tanner M, Pollitt CC.The dysadhesion and destruction of lamellar basement membrane of laminitis may be due to increased lamellar metalloproteinase activity. Characterising lamellar metalloproteinase-2 (MMP-2) and locating it in lamellar tissues may help determine if laminitis pathology is associated with increased MMP-2 transcription. Objective: To clone and sequence the cDNA encoding lamellar MMP-2, develop antibody and in situ hybridisation probes to locate lamellar MMP-2 and quantitate MMP-2 transcription in normal and laminitis tissue. Methods: Total RNA was isolated, fragmented by RT-PCR, cloned into vector a...
Pollitt CC, Daradka M.Surgical stripping of the hoof wall results in a wound that heals remarkabley well. In contrast, lamellae recovering from laminitis are often deformed. Investigating lamellar wound healing may aid understanding of laminitis. Objective: To document temporal changes in the lamellar basement membrane (BM), dermis and epidermis after surgery. Methods: Wall strips were made in the dorsal hoof wall midline of 6 mature horses. Immunohistochemistry was used to document changes in the basement membrane (BM) and detect proliferation of epidermal cells in lamellar tissues harvested at intervals. A confor...
Daradka M, Pollitt CC.Current theories explaining how the hoof wall 'grows' and moves past the stationary distal phalanx are speculative and based on incomplete evidence. Movement in the lamellar region could occur by cell proliferation or an enzyme-based remodelling process. Since laminitis pathogenesis appears to involve increased transcription and activation of enzymes normally involved in tissue remodelling, it is important to know precisely which process dominates the lamellar region of the hoof.. Objective: To investigate epidermal cell proliferation in the equine hoof wall and calculate a proliferative index...
McGowan CM, Frost R, Pfeiffer DU, Neiger R.Serum insulin concentration and its use as a prognostic indicator in horses with equine Cushing's syndrome (ECS) have been poorly documented. Objective: To examine daily insulin variations in horses with ECS and the effect of treatment using trilostane, a competitive inhibitor of 3beta-hydroxysteroid dehydrogenase. Further, we aimed to examine the relationship between baseline serum insulin concentration and survival in horses with ECS. Methods: Basal serum insulin concentrations were measured in 20 confirmed ECS cases by taking blood at regular 4 h intervals for 24 h (1200, 1600, 2000, 2400, ...
van Eps AW, Pollitt CC.The hypometabolic and vasoconstrictive effects of cryotherapy could prevent the development of laminitis. Objective: To use distal limb cryotherapy to prevent laminitis induced by alimentary carbohydrate overload. Methods: Laminitis was induced in 6 Standardbred horses that had one front limb continuously cooled in an ice/water mixture. Lameness evaluation, blinded lamellar histological grading and analysis for lamellar matrix metalloproteinase-2 (MMP-2) mRNA expression were used to evaluate the severity of laminitis. Results: Cryotherapy was well tolerated and effective in cooling the feet. I...
French KR, Pollitt CC.Acute laminitis is characterised by hoof lamellar dermal-epidermal separation at the basement membrane (BM) zone. Hoof lamellar explants cultured in vitro can also be made to separate at the basement membrane zone and investigating how this occurs may give insight into the poorly understood pathophysiology of laminitis. Objective: To investigate why glucose deprivation and metalloproteinase (MMP) activation in cultured lamellar explants leads to dermo-epidermal separation. Methods: Explants, cultured without glucose or with the MMP activator p-amino-phenol-mercuric acetate (APMA), were subject...
Moore RM, Eades SC, Stokes AM.To date, there is a substantial amount of data to support the hypotheses that vascular and enzymatic changes are ongoing in experimental laminitis. Furthermore, there is substantial in vitro evidence that the enzymatic changes weaken the dermo-epidermal attachments leading to mechanical failure of the hoof-bone interface of the equine digit. However, investigators of both the vascular and enzymatic theories have, to date, been unable to substantiate the effects of these pathophysiological changes in vivo on laminar tissues of horses afflicted with experimentally induced or naturally acquired l...
Lansdowne JL, Bouré LP, Pearce SG, Kerr CL, Caswell JL.To compare laparoscopic dissection with-laparoscopic dissection combined with abdominal instillation of ferric hyaluronate gel for the treatment of experimentally induced adhesions in pony foals. Methods: 12 healthy pony foals. Methods: A serosal abrasion method was used to create adhesions at 4 sites on the jejunum (day 0). At day 7 laparoscopy was performed and the adhesions observed in each foal were recorded. In group-1 foals (n = 6), the adhesions were separated laparoscopically (treatment 1). In group-2 foals (n = 6), 300 mL of 0.5% ferric hyaluronate gel was infused into the abdomen aft...
Lopes MA, White NA, Donaldson L, Crisman MV, Ward DL.To assess changes in systemic hydration, concentrations of electrolytes in plasma, hydration of colonic contents and feces, and gastrointestinal transit in horses treated with IV fluid therapy or enteral administration of magnesium sulfate (MgSO4), sodium sulfate (NaSO4), water, or a balanced electrolyte solution. Methods: 7 horses with fistulas in the right dorsal colon (RDC). Methods: In a crossover design, horses alternately received 1 of 6 treatments: no treatment (control); IV fluid therapy with lactated Ringer's solution; or enteral administration of MgSO4, Na2SO4, water, or a balanced e...
Livengood JL, Lanka S, Maddox C, Tewari D.Streptococcus equi subspecies equi (S. equi), the causative agent of strangles, is an important equine pathogen. Strangles is a highly contagious disease and a commercial modified live vaccine (MLV) is used for protection, which although effective, may also result in clinical signs of the disease. A rapid means to differentiate between the MLV and wild-type infection is crucial for quarantine release and limiting the disease spread. This study describes the use of a pyrosequencing assay targeting a single nucleotide deletion upstream of the SzPSe gene to distinguish between the wild-type and v...
Drudge JH, Lyons ET, Swerczek TW, Tolliver SC.Cambendazole (CBZ) treatments (20 mg/kg) given at 8-week intervals were used for parasite control in a breeding band of ponies (n = 33 to 43) during the period July 1974 to August 1978. Pre- and posttreatment worm egg counts on feces were used to evaluate efficacy of treatments after every 2nd treatment interval by monitoring changes in strongyle egg counts. Initially, effective reductions (expressed as 92% to 96% fewer worm eggs) were lessened to 70% by the 9th treatment (18 months) and to 28% by the 12th treatment, and thereafter, they fluctuated between 0% and 38%. Critical tests on animals...
Hawkins JF, Tulleners EP.Epiglottitis was diagnosed and treated in 20 horses (13 Thoroughbreds and 7 Standardbreds) over a 5-year period. Eighteen horses were used for racing, and 2 Standardbreds were broodmares. Primary clinical signs were exercise intolerance, respiratory noise, and coughing. The most common endoscopic diagnosis made by referring veterinarians was epiglottic entrapment (11 horses). In 19 horses, endoscopic evaluation at admission revealed mucosal ulceration and thickening of the lingual surface of the epiglottis. Other endoscopic findings included dorsal displacement of the soft palate (14 horses), ...
Moore BR.Lower respiratory tract disease is an important source of poor performance and exercise intolerance in racehorses and middle-aged sport horses. Horses that perform high-intensity exercise are predisposed to development of infectious and noninfectious respiratory disease. Diagnostic aids for investigation of lower respiratory tract disease include thorough thoracic auscultation with rebreathing, endoscopic examination, bronchoalveolar lavage (BAL), and thoracic radiographic examination. The therapeutic approach for horses with lower respiratory tract diseases often can be directed by cytologic ...
Cox A, Wood K, Coleman G, Stewart AJ, Bertin FR, Owen H, Suen WW, Medina-Torres CE.To assess the efficacy of an herbal spray combining various essential oils, with a claim of mast cell stabilisation, antipruritic, anti-inflammatory, and insect repellent effects on the clinical presentation of insect bite hypersensitivity (IBH) in horses. Methods: Double-blinded, placebo-controlled, randomised, cross-over clinical trial. Methods: Twenty adult horses with clinical IBH were treated with a daily application of herbal spray or placebo for 28 days in a randomised, cross-over fashion, separated by a>28-day washout period. Horses were examined and scored prior to and after the co...
Lakritz J, Madigan J, Carlson GP.Hypovolemic hyponatremia attributable to severe fluid and electrolyte alterations was diagnosed in a foal with diarrhea. Subsequent consumption of water resulted in rapid reduction of serum sodium concentration and serum osmolar depression. Clinical signs of neurologic disease developed including blindness, loss of menace response, and seizures. Treatment of this condition with IV administered fluids included hypertonic saline solution (7.2%; 2 ml/kg of body weight), and frequent monitoring of serum electrolyte concentrations and osmolality resulted in gradual correction of the fluid and elect...
Nolen-Walston RD, Parente EJ, Madigan JE, David F, Knafo SE, Engiles JB.This clinical report describes 8 cases of branchial remnant cysts (BRC) in the horse. The horses presented with bimodal age distribution, with 5 cases in mature horses (age 8-21 years) and 3 in foals (age 1, 6 and 10 months). Mature cases presented for dysphagia or intermittent oesophageal obstruction (2/5), and retropharyngeal swelling (3/5), whereas respiratory stridor and visible mass were presenting complaints in the foals. Presence of a right-sided (5/8) or dorsally located (2/8) palpable retropharyngeal mass of 3-35 cm diameter was noted clinically; one left-sided mass was identified as ...
Imhasly A, Frey CF, Mathis A, Straub R, Gerber V.The protozoon parasite Cryptosporidium parvum is an important cause of diarrhea in farm animals, but it can also infect other animals and humans. In this case report, oocysts of Cryptosporidium spp. were microscopically detected by modified Ziehl-Neelsen staining in the feces of a 9 day old Arabian colt presented with yellowish, foul smelling, diarrhea and fever of 40 degrees C. PCR and sequencing of the isolate revealed C. parvum (bovine genotype). Hemato-chemical analysis of the foals blood revealed a marked hypogammaglobulinaemia (IgG 108mg/dl). The colt responded well to a supportive thera...
Ronéus B, Lindblad A, Lindholm A, Jones B.Hyaluronate and cartilage proteoglycan fragments in synovial fluid from normal equine joints were determined after repeated intraarticular injections of beta-methasone, methylprednisolone, hyaluronate, saline and a combination of beta-methasone + hyaluronate and methylprednisolone + hyaluronate. The experimental intraarticular treatments were given at the beginning of the study and after one and two weeks. Synovial samples were obtained at the onset of the study and after 1, 2, 3, 4, 6, and 8 weeks. The synovial volume was determined and showed no significant changes after the repeated arthroc...
Hübers E, Bauer N, Fey K, Moritz A, Roscher K.The retrospective study aimed to evaluate the prevalence of true thrombocytopenia and ethylenediaminetetraacetic acid (EDTA)-induced pseudothrombocytopenia in horses and ponies and to assess the diagnostic and prognostic utility of true thrombocytopenia. Methods: In 3592 patients (2008-2015) hematological data (ADVIA® 2120, Siemens) were reviewed. Inclusion criteria were platelet counts < 90 x 109/l (EDTA-blood) and/or < 84 x 109/l (citrate blood). Thrombocytopenia was classified as true, EDTA-induced, and questionable. Patients with true thrombocytopenia were assigned to nine groups ac...
Weinhart G, Götz E, Götz HJ.Polydactylism, an excess deformity in a foal is described. The hereditary pathology and etiopathogenesis are discussed. A method of surgical correction of the deformed extremity is introduced. Indication and prognosis of the surgical correction of polydactylism and aspects concerning the breeding management are discussed.
Adair HS, Goble DO, Vanhooser S, Blackford JT, Rohrbach BW.The antebrachiocarpal and tarsocrural joints of 10 adult horses were randomly assigned to 1 of 4 groups. Groups were formulated and were treated as follows: group 1, control (arthrocentesis only); group 2, buffered lactated Ringer solution; group 3, 10% dimethyl sulfoxide (DMSO; w/v) in lactated Ringer solution; and group 4, 30% DMSO (w/v) in lactated Ringer solution. Joints were lavaged once with the respective solution. Prior to lavage and on days 1, 4, and 8 after lavage, all horses were evaluated for lameness and joint effusion; synovial fluid total and differential WBC counts, synovial fl...
Wong D.The clinical signs of horses diagnosed with equine influenza (EI) at Centennial Parklands Equestrian Centre (CPEC) and the events surrounding their diagnosis are described. This was the site of the first case of EI diagnosed outside of the Eastern Creek Animal Quarantine Station. The clinical data demonstrate the rapid spread of the disease after a sufficient viral load had developed from the initial cases within CPEC.
Vallone LV, Neaderland MH, Ledbetter EC, Dubielzig RR.To describe clinical, in vivo confocal microscopic, histopathologic, polymerase chain reaction assay for antigen receptor rearrangement (PARR) and immunohistochemical features of a horse with suspected malignant transformation of corneal B lymphocytes in immune-mediated keratitis (IMMK) and to also report surgical management and adjunctive treatment including topical and radiation therapies. Methods: A 15-year-old Oldenburg gelding was examined for presumptive progressive stromal IMMK of the right eye which became refractory to medical management. Corneal in vivo confocal microscopy revealed...
Davis JL, Gardner SY, Jones SL, Schwabenton BA, Papich MG.The properties of azithromycin suggest that it may be an alternative to erythromycin for treatment of Rhodococcus equi pneumonia in foals. To investigate this possibility, the disposition of azithromycin in plasma, polymorphonuclear leukocytes (PMN), and alveolar cells was examined after a single administration in foals. Azithromycin suspension was administered orally (p.o.) at a dose of 10 mg/kg to five healthy 2-3-month-old foals. Two weeks later, azithromycin for injection was administered by intravenous (i.v.) infusion at a dose of 5 mg/kg to the same foals. Plasma samples were collected a...
Murphy JR, McPherson EA, Lawson GH.80 mg sodium cromoglycate (SCG) was administered by inhalation to two COPD-affected animals known to have respiratory hypersensitivity to Micropolyspora faeni. SCG treatment 20-30 minutes prior to inhalation challenge with M. faeni prevented exacerbation of respiratory disease, usually seen 4-8 hours after challenge. duration of protection against antigen challenge after a single SCG treatment was 4-5 days. The duration of protection was not prolonged by reducing the frequency of antigen challenge. Multiple antigen challenge, using M. faeni and Aspergillus fumigatus, shortened the protective p...
Moore RM, Muir WW, Bertone AL, Beard WL.Effects of low-flow ischemia and reperfusion of the large colon on systemic and colonic hemodynamic and metabolic variables were determined in horses. Twenty-four adult horses were randomly allocated to 3 groups: sham-operated (n = 6), 6 hours of ischemia (n = 9), and 3 hours of ischemia and 3 hours of reperfusion (n = 9). Low-flow ischemia was induced in groups 2 and 3 by reducing colonic arterial blood flow to 20% of baseline. Heart rate, arterial blood pressures, cardiac index, pulmonary artery pressure, right atrial pressure, and colonic blood flow were monitored. Arterial, mixed-venous, a...
James S, Daffy J, Cook J, Samiric T.Fluoroquinolone antibiotics are associated with increased risk of tendinopathy and tendon rupture, which can occur well after cessation of treatment. We have previously reported that the fluoroquinolone ciprofloxacin (CPX) reduced proteoglycan synthesis in equine tendon explants. This study aimed to determine the effects of CPX on proteoglycan catabolism and whether any observed effects are reversible. Equine superficial digital flexor tendon explant cultures were treated for 4 days with 1, 10, 100 or 300 µg/mL CPX followed by 8 days without CPX. The loss of [S]-labelled proteoglycans and che...
Carlson GP, O'Brien MA.Anaerobic bacterial pneumonia with septicemia was diagnosed in 2 Thoroughbred racehorses referred with respiratory tract disease that had failed to respond to initial treatment with various antibiotics including penicillin and trimethoprim-sulfamethoxazole. Multiple anaerobic organisms, including Bacteroides spp and Fusobacterium spp, were isolated from blood and transtracheal aspirates obtained from both horses and from aspirates of cutaneous nodules obtained from 1 horse. The latter horse responded to metronidazole treatment followed by procaine penicillin G administration and regained its h...
Amaral A, Fernandes C, Szóstek-Mioduchowska A, Lukasik K, Rebordão MR, Pinto-Bravo P, Skarzynski DJ, Ferreira-Dias G.Cathepsin G (CAT) is a protease released by neutrophils when forming neutrophil extracellular traps that was already associated with inducing type I collagen (COL1) in equine endometrium in vitro. Endometrosis is a fibrotic condition mainly characterized by COL1 deposition in the equine endometrium. The objective was to evaluate if noscapine (an alkaloid for cough treatment with anti-neoplastic and anti-fibrotic properties) would reduce transcription (evaluated by qPCR) and COL1 protein relative abundance (evaluated by western blot) induced by CAT in equine endometrial explants from follicula...
Vullo V, Mastroianni CM, Lichtner M, Mengoni F, Chiappini E, D'Agostino C, Delia S.Thirty healthy blood donors, 15 workers from horse-breeding farms, 69 human immunodeficiency virus (HIV)-negative persons at risk for HIV infection, 125 HIV-infected subjects without Rhodococcus equi infection, and nine HIV-infected patients with Rhodococcus equi pneumonia were evaluated in order to detect serum antibodies to Rhodococcus equi precipitate-soluble antigen by an enzyme immunoassay (EIA). Whereas EIA values for healthy donors, horse farm workers, individuals at risk for HIV infection, and HIV-positive subjects without Rhodococcus equi infection were comparable, HIV-infected patien...
Diel de Amorim M, Chenier TS, Card C, Back B, McClure JT, Hanna P.Hydropsical conditions are exceedingly rare in the horse. However, when they occur, they are true emergencies due to the severe enlargement of the pregnant uterus, which can result in clinical signs, such as an enlarged round abdomen, dyspnea, reluctance to walk, and colic, and may lead to the development of abdominal wall disease. The pathogenesis of hydropsical conditions is not fully elucidated, but they have been associated with placentitis and fetal abnormalities. This report describes six cases of hydropsical conditions in mares with or without concurrent abdominal wall disease. Five out...
Harman J, Ward M.Equine Cushing's syndrome, a relatively common and complex condition, is difficult to treat with conventional medicine. Cushing's syndrome involves a hyperplasia or adenoma of the anterior pituitary gland. Biochemical alterations include increased endogenous cortisol, insulin resistance, elevated adrenocorticotrophic hormone, and decreased thyroid hormone levels. Symptoms include hirsutism with no loss of the winter coat in summer, refractory laminitis, weight problems (over- or underweight), polyuria/polydipsia (Pu/Pd), frequent infections, lowered immunity to intestinal parasites, decreased ...
Steffey EP, Woliner MJ, Puschner B, Galey FD.To quantitate the effects of desflurane and mode of ventilation on cardiovascular and respiratory functions and identify changes in selected clinicopathologic variables and serum fluoride values associated with desflurane anesthesia in horses. Methods: 6 healthy adult horses. Methods: Horses were anesthetized on 2 occasions: first, to determine the minimum alveolar concentration (MAC) of desflurane in O2 and second, to characterize cardiopulmonary and clinicopathologic responses to 1X, 1.5X, and 1.75X desflurane MAC during both controlled and spontaneous ventilation. Results: Mean +/- SEM MAC ...
Van Hoogmoed LM.Intestinal stasis or ileus is a significant cause of mortality and morbidity in horses and has been attributed to a variety of causes, including loss of intrinsic or extrinsic electrical activity, incoordination of contractile activity from regional stimuli, and dissociation between electrical and mechanical activity. Proposed mechanisms include systemic shock, electrolyte disturbances, persistent luminal distention, ischemia, inflammation, peritonitis, endotoxemia, and anesthesia. Because the cause of ileus is likely multifactorial, a variety of pharmaceutics have been used to target specific...
Jukic CC, Cowling NR, Perkins NR, van Eps AW, Ahern BJ.Laser salpingopharyngostomy has been used as an adjunct to primary medical therapy allowing for topical debridement, topical treatment or to potentially alter the guttural pouch environment in horses with guttural pouch disease. Objective: To evaluate the effect of a laser salpingopharyngostomy on the guttural pouch environment in healthy horses. Methods: Experimental study. Methods: In six adult Standardbred female horses, under standing sedation a stab incision was made ventral to the sternocephalicus tendon and a customised trocar inserted into the medial guttural pouch compartment. Baselin...
Freeman DE, Schaeffer DJ.Although experimental studies have demonstrated differences in performance between methods for handsewn jejunojejunostomy in horses, information on clinical results after different methods of anastomosis are rare. Objective: A continuous Lembert pattern wrapped in a carboxymethylcellulose and hyaluronate membrane would perform better than an interrupted Lembert pattern for jejunojejunostomy in horses. Methods: Data was reviewed on 32 horses that underwent jejunojejunostomy from 1993-2002. Kaplan-Meier analyses and rates for post operative colic and death were used to compare outcomes after an ...
Gibson KT, McIlwraith CW, Park RD, Norrdin RW.Medial patellar desmotomy was performed on one (treated) hindlimb, and a sham operation on the other (control) hindlimb, of 12 normal horses. The horses were examined for lameness before medial patellar desmotomy and at months 1, 2, and 3. The femoropatellar joints were examined radiographically and arthroscopically at month 3. All horses were lame on the treated limb at months 1, 2, or 3. Radiographic changes, including fragment formation at the distal aspect of the patella and bone production at the attachment of the middle patellar ligament on the patella, were present in 11 horses at month...
Willingham-Lane JM, Berghaus LJ, Berghaus RD, Hart KA, Giguère S.The soil-dwelling, saprophytic actinomycete is a facultative intracellular pathogen of macrophages and causes severe bronchopneumonia when inhaled by susceptible foals. Standard treatment for disease is dual-antimicrobial therapy with a macrolide and rifampin. Thoracic ultrasonography and early treatment with antimicrobials prior to the development of clinical signs are used as means of controlling endemic infection on many farms. Concurrently with the increased use of macrolides and rifampin for chemoprophylaxis and the treatment of subclinically affected foals, a significant increase in t...
Douthit TL, Bormann JM, Gradert KC, Lomas LW, DeWitt SF, Kouba JM.This experiment was conducted to evaluate if consumption of endophyte-infected fescue alters digital circulation in the distal thoracic limb of the horse and to assess if soundness of the hooves of horses is affected by consumption of endophyte-infected fescue. Twelve American Quarter Horses (mean initial BW 459 ± 31 kg), 6 mares and 6 geldings, were used in this 90-d study that comprised high-endophyte (E+) and low-endophyte (E-) treatment groups. Fescue seed was integrated into the E+ diet at a rate sufficient to bring total ergovaline to 200 μg/kg, and endophyte-free fescue seed was incor...
