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.
Schneider M, Fey K, Tellhelm B, Litzke LF, Sasse HH.This article reports a case of guttural pouch bleeding which was managed successfully by using intravascular embolisation systems to occlude the damaged vessels. Percutaneous catheterisation of the common carotid artery allowed angiographic visualisation of the main head arteries: A. carotis externa, A. carotis interna and A. occipitalis, which showed no abnormalities angiographically. Originating from the A. occipitalis, one artery sent smaller, extensively branching and tortuous vessels to the guttural pouch area. This branching was interpreted as a sign of inflammatory hypervascularization....
Brashier MK, Geor RJ, Ames TR, O'Leary TP.To determine whether supplemental i.v. calcium administration would attenuate or prevent gentamicin-induced acute renal failure, defined as an increase in serum creatinine concentration > or = 50% above baseline. Methods: 10 healthy pony mares. Methods: Pony mares were randomly assigned to receive calcium at a dosage of 20 mg/kg of body weight or saline solution i.v., twice daily for 14 days. All pony mares received gentamicin at a dosage of 20 mg/kg i.v. every 8 hours for 14 days. Gentamicin pharmacokinetic, serum biochemical, and urinalysis data were measured every other day for the 14-da...
Rush BR, Flaminio MJ, Matson CJ, Hakala JE, Shuman W.To determine cytologic changes in horses with recurrent airway obstruction (heaves) after administration of aerosolized beclomethasone dipropionate and dexamethasone parenterally. Methods: 6 horses with inducible and reversible heaves. Methods: Episodes of heaves were induced by exposure to moldy hay and straw for 7 days. Horses were assigned to treatment groups (aerosolized beclomethasone, parenterally administered dexamethasone, aerosolized propellant), and pulmonary inflammation was evaluated by serial cytologic examination of bronchoalveolar lavage (BAL) fluid samples obtained on days 0, 7...
Rush BR, Raub ES, Rhoads WS, Flaminio MJ, Matson CJ, Hakala JE, Gillespie JR.To determine changes in clinical signs of disease and response to pulmonary function testing in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. Methods: 6 horses with inducible and reversible heaves. Methods: Episodes of heaves were induced by exposure (challenge) to moldy hay and straw for 7 days. Horses were assigned to treatment groups (aerosolized beclomethasone dipropionate, parenterally administered dexamethasone, aerosolized propellant [control]), and respiratory frequency and s...
Young LE, Blissitt KJ, Clutton RE, Molony V.To evaluate temporal hemodynamic effects of dobutamine in horses anesthetized with halothane. Methods: 8 adult Thoroughbreds. Methods: Anesthesia was induced by i.v. administration of romifidine and ketamine and maintained using halothane in oxygen. After 60 minutes, dobutamine was administered i.v. for 60 minutes at 4 micrograms/kg of body weight/min. Measurements of left ventricular function were obtained by transesophageal echocardiography and cardiac catheterization. Results: Mean, systolic, diastolic, aortic, pulmonary arterial, and left and right ventricular end-diastolic and systolic pr...
Rush BR, Worster AA, Flaminio MJ, Matson CJ, Hakala JE.To determine alteration in adrenocortical function in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. Methods: 6 horses with inducible and reversible heaves. Methods: Episodes of heaves were induced by exposure to moldy hay and straw for 7 days (natural challenge). Horses then underwent treatment (aerosolized beclomethasone, parenterally administered dexamethasone, and aerosolized propellant) for 7 days. Horses remained in the mold-contaminated environment for 7 days after discontinuat...
Sprayberry KA, Madigan J, LeCouteur RA, Valentine BA.A Thoroughbred-Percheron crossbred gelding developed a fulminant cascade of sequelae following a severe episode of rhabdomyolysis. Complications may occur with rhabdomyolysis of any etiology. In warmblood horses with Percheron bloodlines, rhabdomyolysis may be secondary to polysaccharide storage disease, and aggressive therapy should be undertaken promptly to avoid the complications.
Valk N, Doherty TJ, Blackford JT, Abraha TW, Frazier DL.The effect of cisapride pretreatment on gastric emptying in horses was determined by measuring serum concentrations of acetaminophen, a drug known to be readily absorbed in the small intestine but not in the stomach. The time to reach maximum serum acetaminophen concentrations (Tmax), the maximum serum concentrations (Cmax) and the area under the serum acetaminophen concentration vs. time curves (AUC) were compared among treatment groups. In the first part of the study, the effect of orally administered cisapride (0.1, 0.2 and 0.4 mg/kg bwt) on gastric emptying was examined in 6 normal fasted ...
Craven J, Bjørn H, Henriksen SA, Nansen P, Larsen M, Lendal S.This study reports on the prevalence of anthelmintic resistance in strongyles of horses in Denmark. Of 5 methods used for the calculation of faecal egg count reduction (FECR) the method recommended by the World Association for the Advancement of Veterinary Parasitology, for the detection of resistance in sheep was the most sensitive procedure for detecting resistance. Using this method benzimidazole resistance was detected on 33 of 42 farms (79%) examined. Pyrantel was tested on 15 farms and FECR tests indicate resistance on 3 (30%) farms. On 2 farms on which resistance to pyrantel was detecte...
Raisis AL, Hodgson JL, Hodgson DR.Twenty-one compromised neonatal foals hospitalised at the Rural Veterinary Centre (RVC) during 1993 were studied to determine i) serum gentamicin concentrations obtained when gentamicin was administered at 3.3 mg/kg bwt twice daily i.m.; ii) factors which contributed to inter-foal variation in serum gentamicin concentrations achieved and iii) clinical efficacy of gentamicin therapy in foals with confirmed septicaemia. Septicaemia was confirmed in 7 foals with positive blood cultures and suspected in 8 foals with a sepsis score > 11. Peak serum concentrations (Ps) were > 6 microg/ml in al...
Fecteau KA, Haffner JC, Eiler H.The purpose of this study was to determine to what degree bacterial collagenase may digest human placentae compared to equine and bovine placentae. Placenta samples from human, equine and bovine were incubated with bacterial collagenase solution at various concentrations. The degree of hydrolysis and collagen breakdown was measured by the release of total proteins and hydroxyproline into the incubation media. Also, whole placentae were injected via umbilical cord arteries with collagenase solution (200 U/ml, 200 ml total volume in human and 1000 ml in equine) and hydrolysis determined chemical...
Soliman GA.The pharmacokinetic behaviour of gentamicin sulphate (3.4 mg/kg bwt) was studied following its intramuscular injection to a group of horses and to another group of horses premedicated with sodium methyl arsinate (2 mg/kg bwt) or imidocarb dipropionate (4.8 mg/kg bwt). Considerable differences were observed in the pharmacokinetics of gentamicin in pre-medicated horses and in horses which had received the antibiotic alone. Peak serum concentration of gentamicin (9.85 +/- 0.05 and 11.15 +/- 0.15 micrograms/ml) were attained within 1.45 +/- 0.05 and 0.92 +/- 0.04 h in arsinate and imidocarb-medica...
Murray RC, DeBowes RM, Gaughan EM, Zhu CF, Athanasiou KA.Intra-articular corticosteroids are widely used as anti-inflammatory agents for symptomatic management of arthritis, but their administration with concurrent exercise remains controversial. Biochemical and morphologic analysis of treated cartilage has revealed conflicting results, but previous biomechanical assessment has not been undertaken. Objective: To compare the biomechanical properties of intra-articular methylprednisolone acetate (MPA) and diluent treated cartilage in treadmill exercised horses. Methods: Eight 2-year-old female horses had MPA or diluent administered into contralateral ...
Marr KA, Lees P, Page CP, Cunningham FM.Leukotrienes have been shown to mimic many of the pathophysiological processes in allergic airway disease. In this study the bronchoconstrictor effect of inhaled LTD4, and radiolabelled neutrophil accumulation in response to inhalation of LTB4, have been examined in the horse. In separate studies, solutions of LTD4 and LTB4 were administered to the airways of normal animals by nebulisation. LTD4, but not LTB4, caused a dose-dependent increase in pleural pressure which was maximal at three to four minutes and had returned to baseline by 15 to 20 minutes. On a molar basis LTD4 was 305 to 970 tim...
Nelson KM, Schram BR, McGregor MW, Sheoran AS, Olsen CW, Lunn DP.Inactivated alum-adjuvanted conventional equine influenza virus vaccines are of poor efficacy and offer limited short-term protection against infection. In sharp contrast, natural infection with equine influenza virus confers long-term protective immunity. In order to identify the protective immune responses to equine influenza virus, the influenza virus-specific IgA, IgGa, IgGb, IgGc and IgG(T) antibody responses in nasal secretions and serum induced by natural infection and a commercial vaccine were studied by ELISA. Two groups of four influenza-naive ponies were established. In the natural ...
Kelley LC, Mahaffey EA.Gross lesions, microscopic appearance, and immunophenotyping are reported in a retrospective study of 31 cases of equine malignant lymphoma. Immunohistochemical studies were performed on archived formalin-fixed, paraffin-embedded tissues. Monoclonal antibodies to surface glycoprotein BLA.36 and intracytoplasmic domains of mb-1 and B29 were used to document the presence of B lymphocytes in the equine tumors. Polyclonal antibody to CD3 and monoclonal antibodies to T-lymphocyte markers CD3 and CD5 revealed the presence of variable numbers of T cells within the equine lymphomas. The neoplastic com...
Paterson DL, Murray PK, McCormack JG.Twenty-three horses and three humans in Queensland, Australia, were infected with a novel member of the Paramyxoviridae family of viruses in two geographically distinct outbreaks. Two of the humans died-one died of rapid-onset respiratory illness, and the other died of encephalitis. The third infected human developed an influenza-like illness and made a complete recovery. All infected humans had close contact with sick horses. Since the two outbreaks occurred at sites 1,000 km apart and no known contact between the two groups of humans and horses occurred, extensive testing of animals and bird...
Marr KA, Lees P, Page CP, Cunningham FM.The leukotrienes (LT) LTD4 and LTB4 have been shown to cause bronchoconstriction and neutrophil accumulation, respectively, in horse lungs. Such changes are characteristic of the equine allergic respiratory disease, chronic obstructive pulmonary disease (COPD). To further investigate the role of these putative mediators in the pathogenesis of equine COPD the effect of a 5-lipoxygenase inhibitor, fenleuton, on antigen-induced changes in horses with this condition has been examined. Six horses with COPD underwent a series of four antigen challenges, one month apart, with placebo pre-treatment on...
Biswas B, Vemulapalli R, Dutta SK.Ehrlichia risticii, the causative agent of Potomac horse fever, has recently been isolated from many vaccinated horses with typical clinical signs of the disease. The heterogeneity of the E. risticii isolates obtained from the vaccinated horses necessitates the identification of the molecular basis of strain variations to elucidate the vaccine failure and to aid in the development of an efficient vaccine against this disease. As an attempt, two major cross-reacting surface antigen genes of 50- and 85-kDa antigens, present separately in strains 25-D (isolated in 1984) and 90-12 (isolated in 199...
Newton SA.Bacterial infections (such as meningitis or meningoencephalitis) of the central nervous system are rare in horses. They are most prevalent in neonates as a result of septicaemia. A few cases have been reported in the adult and most have been fatal. Streptococcal species appear to be the organism most commonly identified in these cases. Thus, this disease may be a secondary complication of upper respiratory tract infections. Clinical signs are extremely variable making diagnosis difficult. In most cases, postmortem has been the definite diagnostic procedure. This paper describes the clinical co...
Palmer JL, Bertone AL, Malemud CJ, Mansour J.To determine if arthroscopic synovectomy in normal and inflamed joints had temporal or site-related effects on articular cartilage. Methods: Alterations in equine third carpal bone articular cartilage were studied at two time periods: groups 1 and 2 (6 weeks) and groups 3 and 4 (2 weeks) after synovectomy in normal (groups 2 and 4) and inflamed carpi (groups 1 and 3). Methods: 16 carpi from eight horses. Methods: Biochemical and biomechanical properties of dorsal and palmar articular cartilage were determined by radioloabeling, proteoglycan (PG) extraction, chromatography, electrophoresis, and...
Watt BC, Foerner JJ, Haines GR.To describe incomplete oblique sagittal dorsal cortical fractures of the equine third metacarpal bone, their surgical repair, and subsequent performance of the horses. Methods: Retrospective examination of medical records and racing performance. Methods: Six Thoroughbred race horses, 2 to 4 years of age. Methods: Radiographic confirmation of all fractures preceded general anesthesia and surgical correction. Three fractures were treated by intracortical compression using screws placed in lag fashion, and five fractures were treated by osteostixis. Race records were reviewed for each horse to de...
Doyle AJ, Saab ME, Lewis K, McClure JT.Alcohol-based antisepsis has been extensively studied in human health care, but only little information is available regarding efficacy and tolerance in other species. The purpose of this study was to determine if an alcohol-based antiseptic is effective at reducing bacterial counts on equine skin and the appropriate contact time to do so, without causing any adverse skin reactions. Samples were collected before and after preparation from clipped sites over both jugular veins of horses and were plated on 3M Petrifilm Aerobic Count Plates in duplicate. Trial 1 tested an alcohol-based product (E...
Malalana F.Ocular abnormalities are a common finding in aged horses. Although these seldom cause overt visual deficits detected by their owners, they can be a source of chronic or acute discomfort so early detection, and treatment when available, is essential. Some of these abnormalities are specific to old horses, whereas others are a result of ongoing disease or inflammation that started earlier in life but that becomes more evident when the damage sustained to the eye is advanced. If vision is significantly affected, consideration of human safety and animal welfare is paramount.
Valdez RA, DiPietro JA, Paul AJ, Lock TF, Hungerford LL, Todd KS.The bioequivalence of Strongid C and generic pyrantel tartrate was determined in a controlled study using 30 horses with naturally acquired endoparasitic infections. Three horses were randomly allocated to each of ten replicates based on quantitative nematode and ascarid egg counts and fecal larvae culture results. Horses within each replicate were randomly assigned to one of three treatment groups. Horses in Treatment Group 1 received only oats; horses in Treatment Group 2 received generic pyrantel tartrate pellets (2.65 mg pyrantel tartrate kg-1) mixed with oats; horses in Treatment Group 3 ...
Bertone AL, Jones RL, McIlwraith CW.The tarsocrural joints of 11 horses were inoculated with 1.2 to 2.16 x 10(6) viable Staphylococcus aureus organisms susceptible to a trimethoprim-sulfadiazine (TMP-SDZ) combination with minimal inhibitory concentration (MIC) of 0.25 micrograms of TMP/ml and 4.75 micrograms of SDZ/ml. Antimicrobial treatment consisted of oral administration of a TMP-SDZ combination--30 mg/kg of body weight given once daily (group-1 horses) or 60 mg/kg given as 30 mg/kg every 12 hours (group-2 horses). Paired serum and synovial fluid samples were obtained before intra-articular inoculation with the S aureus, aft...
Bookbinder LC, Mani R, Carr EA.Contemporary data reflecting local pathogens and their antibiograms is necessary to select empirical antimicrobial therapy for equine neonates. Objective: Describe bacterial isolates associated with equine neonatal infection and their antibiograms in the Midwestern United States. An increase in gram-positive infection and antibiotic resistance compared to previous literature was expected. Methods: Data from 149 fluid samples from 133 foals <30 days of age submitted for bacterial culture between January 2007 and December 2018. Methods: A retrospective evaluation of equine neonatal fluid cu...
Ogilvie GK.The importance of paraneoplastic syndromes is often underestimated in the horse. Clinically, paraneoplastic syndromes can cause greater morbidity than the actual physical presence of the malignant tumor. The appearance may be the first sign of a malignancy and may be so severe that appropriate therapy for the underlying cancer is not initiated. This article reviews some of the most common paraneoplastic syndromes that are likely to occur in the horse.
Koenig JB, Sawhney S, Cote N, LaMarre J.To determine whether inflammation of the jejunum of horses decreases the number of motilin receptors and amounts of motilin receptor mRNA and alters erythromycin lactobionate binding affinity to the motilin receptor in jejunal tissues. Methods: Jejunal segments in 6 adult horses. Methods: Each horse was anesthetized, and a ventral median celiotomy was performed; 2 segments of jejunum underwent a sham operation, 2 segments underwent ischemic strangulation obstruction (ISO), and 2 segments underwent intraluminal distension (ILD). Treatments were maintained for 120 minutes. From each segment, ful...
Amann RP, Bowen JM, Pickett BW, Berndtson WE, Stashak RS, Voss JL.Twenty stallions were used to determine if the anthelmintic cambendazole affected seminal characteristics, spermatogenesis, concentration of testosterone in blood serum, or weights of the reproductive orgrans. With minor exceptions, significant differences were not found between values for 10 control and 10 stallions treated with a single oral dose (40 mg/kg body weight) of cambendazole. The treatment did not affect reproductive function and it was concluded that the drug should have no effect on the fertility of stallions.
May SA, Hooke RE, Lees P.There is increasing evidence that the chondrocyte is capable of considerable anabolic and catabolic activity. In the case of equine chondrocytes, this study demonstrates that a variety of factors involved in the pathogenesis of joint disease stimulate the production of prostaglandin E2. These include exposure to IL-1, bone fragments and LPS. In addition, an IL-1-like factor was shown to be produced by the chondrocyte itself, when stimulated by LPS, providing a possible mechanism for amplification of extra-cartilagenous signals and even autocrine control. Considered together with evidence of in...
Miller PJ, Holmes JR.Beat-to-beat variation in the amplitude of the QRS waveform from 13 horses with second degree partial atrioventricular block was examined using an orthogonal lead (X,Y,Z) system. The peak positive deflections (XR, YR and ZR) and peak negative deflections (XQS, YS and ZQ) were regressed against PR and RR intervals. XQS was used to indicate that the peak negative deflection in X could have been a Q or S wave. XR and YR were directly related to PR (P less than 0.001) and XQS and YS were inversely related to PR (P less than 0.001). YR was also directly related to RR (P less than 0.001) but not so ...
Vatistas NJ, Meagher DM, Gillis CL, Neves JW.Twenty-two horses were examined because of firearm injuries. Nine had been shot with .22-caliber bullets, 2 with BB pellets, 6 with buckshot, 1 with a .35-caliber bullet, and 1 with an airgun pellet. Injury was confined to the skin or skeletal muscles in 8 horses. Of these, 7 returned to their previous use. In 14 horses, injuries to additional structures were incurred, including the sinus and pharynx (n = 2), mandible (n = 1), tooth (n = 1), aorta (n = 1), eye (n = 3), tibia (n = 1), gastrointestinal tract (n = 3), joint (n = 1), and trachea (n = 1). The 3 horses that had only eye injuries wer...