Caprine serum fraction immunomodulator as supplemental treatment of lower respiratory disease in the horse

Suppurative lower airway disease is a common debilitating disease in performance horses and, while rarely fatal, is often recalcitrant to conventional therapy. A variety of treatments have been used to combat this condition and we conducted two types of studies to determine if caprine serum fraction--immunomodulator (CSFI), a nonspecific immunomodulator, improved recovery from lower respiratory disease. Two dose response studies were performed to ascertain the efficacy of CSFI. Horses were maintained daily on conventional antibiotic therapy. Respiratory tract exudate, nasal discharge, dyspnoea, chest auscultation and cough frequency were monitored weekly. One hundred percent of the horses treated with 2 i.m. injections of either 60 or 120 mg CSFI one week apart showed significant improvement with each weekly evaluation and were fully recovered by week 3. Horses treated with 15 or 30 mg CSFI did not differ significantly from the control group. Only 10% of the control horses responded to conventional antibiotic therapy. An expanded field trial utilising 80 horses diagnosed with lower respiratory disease and housed at 4 equine clinics was conducted. Thirty-five percent of the 40 control horses, treated solely by conventional antibiotic therapies, recovered while 75% of the horses treated with a supplemental administration of 60 mg CSFI as described above recovered. The combined data from these studies showed that CSFI was able to promote an overall recovery from lower respiratory disease of 86%.     

Efficacy of a 2-dose regimen of a sustained release ceftiofur suspension in horses with Streptococcus equi subsp. zooepidemicus bronchopneumonia

The efficacy and safety of sustained release ceftiofur administered twice, 4 days apart, for treatment of horses with naturally acquired Streptococcus equi subsp. zooepidemicus (Strep. zoo.) pneumonia was evaluated in a multicenter, placebo-controlled, double-blinded, randomized clinical trial. The study included 373 horses (278 treated and 95 placebos) with naturally acquired pneumonia. Inclusion in the statistical analyses for treatment efficacy for Strep. zoo. required recovery of ≥10(4) CFU/mL of Strep. zoo. on the primary isolation plate which resulted in 201 cases (145 treated and 56 placebos) with confirmed Strep. zoo. pneumonia evaluable for treatment success. Therapeutic success was defined by clinical improvement of lower respiratory tract infection at 4 and 9 days after initial dosing, resolution of clinical signs by 15 days, and no recurrence by 25 days. Of the 278 treated horses, 239 (85.9%) completed the 25 day study without additional therapy compared to 50 of the 95 (53.6%) placebo horses. In confirmed Strep. zoo. cases, a clinical cure was achieved in 66.9% of 145 treated horses compared to 32.1% of 56 placebo horses (P = 0.0286). Two doses of sustained release ceftiofur suspension were effective and safe in the treatment of naturally acquired lower respiratory tract infection associated with Strep. zoo. in horses under field use conditions.     

The efficacy of systemically administered anti-arthritic drugs in an induced equine carpitis model

The efficacy of two systemically administered drugs for the treatment of equine joint injuries was assessed in a randomized blinded trial using the chemically induced equine carpitis model previously used to determine the dose and efficacy of both products. After a 10-day acclimation period, carpitis was induced by intracarpal injection of Complete Freund's Adjuvant (CFA) in twenty mature horses free of clinical and radiographic evidence of synovitis or DJD. Five days after model induction, the horses were stratified based on lameness evaluation and randomly assigned to 2 groups of 10 horses each.Parameters evaluated included lameness score, maximum range of carpal flexion, carpal circumference, stride length, and synovial fluid protein. These parameters were measured prior to model induction, 5 days after model induction (immediately prior to initial treatment) and once weekly for 6 weeks. Radiographs of the carpus were taken prior to model induction and 6 weeks. after treatment began. Treatment began 5 days after model induction. One group of 10 horses received 40 mg sodium hyaluronate by intravenous injection weekly for 3 weeks and the other group of 10 horses received intramuscular injections of 500 mg PSGAG every 4 days for 7 treatments.Both treatment groups showed significant improvement from pretreatment baseline values (based upon percent recovery to normal pre-model induction values) for lameness score, stride length and maximum carpal flexion (p<0.05) at each post treatment evaluation. The PSGAG treated group had significant improvement in synovial fluid protein at post treatment weeks 2 and 3. The improvement (percent recovery) in the PSGAG treated group was significantly (p<0.05) better than that of the intravenous sodium hyaluronate treated group for stride and flexion at post treatment weeks 1 through 6, for lameness score at post treatment weeks 1 through 3 and for carpal circumference at post treatment week 4.Both intravenous sodium hyaluronate and intramuscular PSGAG induced significant improvement in clinical lameness parameters; intramuscular PSGAG yielded consistently better results in this experimental model.     

Retropharyngeal lymph node infection in horses: 46 cases (1977–1992)

SUMMARY A retrospective study of 46 horses with retropharyngeal lymph node (RPLN) infection presented to the Rural Veterinary Centre between 1977 and 1992 was undertaken. Horses aged less than one year were most commonly represented (46%). Thirty-nine percent of cases had been exposed to horses with confirmed or suspected strangles (Streptococcus equi subsp equi infection) within the previous 8 weeks. Most frequent signs were unilateral or bilateral swelling of the throat region (65%), respiratory stertor/dyspnoea (35%), purulent nasal discharge (20%), inappetence and signs of depression (15%), and dysphagia (9%). All horses had a soft tissue density in the retropharyngeal region on radiographs. Rhinopharyngoscopy, ultrasonography, haematology as well as cytological and microbial analysis of material aspirated from the soft tissue swelling facilitated diagnosis in some horses. Fifteen horses (33%) were treated with procaine penicillin intramuscularly for 4 to 7 days followed by oral trimethoprim-sulphadimidine for 7 to 14 days. Non-steroidal anti-inflammatory drugs were administered to 6 horses. Four required tracheostomy for severe respiratory distress. The 15 horses treated medically responded to treatment and were discharged from hospital. Three horses (6%) with mild signs received no treatment and recovered uneventfully. Twenty-eight horses (61%) underwent general anaesthesia and surgical drainage of a RPLN abscess. Nineteen received procaine penicillin G for 4 to 7 days. Four of the nine horses that did not receive antibiotic treatment after surgery required further surgical drainage 10 days to 7 weeks after the initial surgery . Limited follow-up information was available for 37 horses. Thirty-two horses were considered to have made complete recovery, 3 horses had died through misadventure and 2 had been euthanased because of chronic ill-thrift .     

Polysaccharide Treatment Reduces Gastric Ulceration in Active Horses

Equine gastric ulceration effects condition, performance, and behavior. Prevalence of ulcers in horses can reach 80% to 100%. After reviewing the literature, we propose an oral polysaccharide preparation will be effective in treating equine gastric ulceration. Ten adult horses with gastric ulceration were used to evaluate the clinical efficacy of a polysaccharide gel containing a blend of hyaluronan and schizophyllan for 30 days. Posttreatment gastroscopies were conducted to determine treatment findings, and images were scored. Percent healing was assessed comparing initial images to posttreatment findings. Of the horses treated with the combinational therapy, 90% showed complete resolution and/or improvement in ulcerative areas, increased appetite, weight gain, and positive behavioral changes. This study provides evidence that gastric ulceration in active horses can be successfully treated with a naturally safe and effective polysaccharide blend of hyaluronan and schizophyllan.     

Treatment with pergolide or cyproheptadine of pituitary pars intermedia dysfunction (equine Cushing's disease)

Medical records of 27 horses (including 13 ponies) treated with pergolide or cyproheptadine for pituitary pars intermedia dysfunction were reviewed to determine the effect of treatment on plasma ACTH, insulin, and glucose concentrations and clinical signs. Prior to treatment, the most common clinical signs were laminitis, hirsutism, and abnormal body fat distribution. The median pergolide dose was 3.0 microg/kg p.o. q24h (range, 1.7-5.5 microg/kg). All horses treated with cyproheptadine were given 0.25 mg/kg p.o. q24h. After pergolide treatment, ACTH concentrations (n = 20; median = 30.4 pg/ml; range, 4.2-173) were significantly lower (P < .01) than those in horses treated with cyproheptadine (n = 7; median = 141.0 pg/ml: range, 10-1,230). Among horses treated with pergolide, there was a correlation between ACTH concentration after treatment and the duration of treatment (P < .001) and pergolide dose (P = .04). Significantly (P = .02) more owners of horses treated with pergolide (85%, 17/20) reported an improvement in clinical signs compared to owners of horses treated with cyproheptadine (28%, 2/7).     

Comparison of the effects of an intravenous lidocaine infusion combined with 1% isoflurane versus 2% isoflurane alone on selected cardiovascular variables and recovery characteristics during equine general anaesthesia

Objectives

To compare the effects of a lidocaine constant rate infusion (CRI) combined with 1% isoflurane versus those of 2% isoflurane alone on cardiovascular variables in anaesthetized horses, and to estimate the sample size required to detect a difference in recovery quality.

Retinal detachment in horses: 40 cases (1998-2005)

OBJECTIVE: To determine clinical features, ophthalmic examination findings, etiology, treatment, and outcome of horses diagnosed with retinal detachment (RD). ANIMALS STUDIED: Forty horses, presented to the North Carolina State University and The Ohio State University Veterinary Teaching Hospitals from 1998 to 2005 that were diagnosed with RD. PROCEDURE(S): Horses with documented RD, confirmed either on ophthalmic examination or by ultrasonography, and with a complete medical record were included. Information retrieved from the medical records included signalment, presenting complaint, duration of clinical signs, ophthalmologic examination findings, diagnostics performed, identified cause of the retinal detachment, treatment given, and outcome. RESULTS: Forty horses (46 eyes) were diagnosed with RD. Mean +/- SD duration of clinical signs of ocular disease was 10.5 +/- 14.7 months. Thirty-four horses presented with unilateral involvement, 6 with bilateral, 14 with partial and 32 with complete RD. Ultrasonography was used to make the diagnosis in 26 eyes, while RD was diagnosed on routine ocular examination in 20 eyes. Bullous RD was the only type of RD observed, although small vitreal traction bands were considered secondary to the underlying inflammation or trauma. RD caused by equine recurrent uveitis (ERU) was diagnosed in 27 of 40 (67.5%) horses. Trauma-induced RD involved 10 of the 40 horses (25%). Presenting problems included known ERU (n = 16), acute or progressive vision loss (n = 9), known ocular trauma (n = 6), cataract (n = 6), and a cloudy cornea (n = 3). No horses regained vision after RD despite therapy. Many eyes were enucleated or eviscerated, or the horses were euthanized. Seven eyes with complete RD were noted to be unchanged and comfortable with medical therapy. CONCLUSIONS: The visual prognosis of RD in horses is grave; however, horses with nontraumatic RD (most commonly ERU) may be able to maintain a comfortable but blind globe with anti-inflammatory medical therapy.     

Infusion of guaifenesin,ketamine, and medetomidine in combination with inhalation of sevoflurane versus inhalation of sevoflurane alone for anesthesia of horses

OBJECTIVE: To evaluate effects of infusion of guaifenesin, ketamine, and medetomidine in combination with inhalation of sevoflurane versus inhalation of sevoflurane alone for anesthesia of horses. DESIGN: Randomized clinical trial. ANIMALS: 40 horses. PROCEDURE: Horses were premedicated with xylazine and anesthetized with diazepam and ketamine. Anesthesia was maintained by infusion of guaifenesin, ketamine, and medetomidine and inhalation of sevoflurane (20 horses) or by inhalation of sevoflurane (20 horses). A surgical plane of anesthesia was maintained by controlling the inhaled concentration of sevoflurane. Sodium pentothal was administered as necessary to prevent movement in response to surgical stimulation. Hypotension was treated with dobutamine; hypoxemia and hypercarbia were treated with intermittent positive-pressure ventilation. The quality of anesthetic induction, maintenance, and recovery and the quality of the transition to inhalation anesthesia were scored. RESULTS: The delivered concentration of sevoflurane (ie, the vaporizer dial setting) was significantly lower and the quality of transition to inhalation anesthesia and of anesthetic maintenance were significantly better in horses that received the guaifenesin-ketamine-medetomidine infusion than in horses that did not. Five horses, all of which received sevoflurane alone, required administration of pentothal. Recovery time and quality of recovery were not significantly different between groups, but horses that received the guaifenesin-ketamine-medetomidine infusion required fewer attempts to stand. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in horses, the combination of a guaifenesin-ketamine-medetomidine infusion and inhalation of sevoflurane resulted in better transition and maintenance phases while improving cardiovascular function and reducing the number of attempts needed to stand after the completion of anesthesia, compared with inhalation of sevoflurane.     

Treatment of respiratory infections in horses with ceftiofur sodium.

Ceftiofur sodium was evaluated as a therapy for respiratory infections in horses. This cephalosporin antimicrobial was administered intramuscularly every 24 h and at a dose of 2.2 mg/kg (1.0 mg/lb) of body weight. The efficacy of ceftiofur sodium was compared with that of a positive control drug, ampicillin sodium (recommended dose of 6.6 mg/kg [3 mg/lb], given every 12 h). Both treatments were continued for 48 h after clinical symptoms were no longer evident (maximum of 10 days). Fifty-five (55) horses with naturally acquired respiratory infections were included in the study; 28 were treated with ceftiofur and 27 with ampicillin. Clinical improvement was recorded for 92.9% of the patients treated with ceftiofur and 92.6% of the animals receiving ampicillin. Both therapies reduced body temperatures to an afebrile level after 2 days of treatment. Complete recovery/cure was noted for 78.6% of the ceftiofur patients and 59.3% of the horses treated with ampicillin. Supporting variables (depression/malaise, respiration/dyspnoea, nasal discharge) were assessed and these also substantiated the effectiveness of the treatments. Both antibiotics were well tolerated. Neither pain nor swelling were noted at the ceftiofur injection site(s). None of the animals developed diarrhoea. Data from this study indicated that ceftiofur sodium is an effective and safe treatment for respiratory infections in horses.     

Osteoarthritis of the talocalcaneal joint in 18 horses

REASONS FOR PERFORMING STUDY: Talocalcaneal osteoarthritis (TO) is an uncommon cause of moderate to severe hindlimb lameness, on which only isolated case reports have been published to date. OBJECTIVES: To review the clinical features of TO and determine optimal methods for diagnosis, management and prognosis. METHODS: The case records from 4 referral centres of 18 horses showing hindlimb lameness considered, as a result of clinical investigation, to be caused by TO, were reviewed. RESULTS: TO affected mature sports and pleasure horses (age 7-16 years) and caused moderate to severe lameness, usually of sudden onset with no obvious inciting cause. There were few localising signs, other than worsening of lameness by hock flexion. Tarsocrural joint analgesia produced improvement in lameness in 6/11 horses (55%) and perineural analgesia of the tibial and fibular nerves complete soundness in 6/14 horses (43%) in which it was performed; 7/14 horses (50%) showed a further substantial improvement. Radiological findings included subchondral bone lysis and sclerosis and irregular joint space width, seen most obviously in a lateromedial view. Nuclear scintigraphy revealed marked uptake of radiopharmaceutical predominantly plantaromedially in the region of the talus in the 7 horses in which it was performed. Fourteen horses were treated conservatively with box- or pasture-rest, with or without intra-articular corticosteroids, hyaluronic acid or polysulphated glycosaminoglycan, and all remained lame. Intra-articular corticosteroids appeared to have no effect in any horse. Of 10 horses receiving conservative management only, 6 were subjected to euthanasia, 3 were retired and 1 remained in light work, but was still lame. Two horses treated by either partial tibial and fibular neurectomy or subchondral forage failed to regain soundness and were retired. Six horses were treated by surgical arthrodesis of the talocalcaneal joint with 2 or three 5.5 mm AO screws introduced obliquely across the joint from the plantarolateral aspect of the calcaneus, which resulted in improvement in lameness in all cases. CONCLUSIONS: Osteoarthritis of the talocalcaneal joint causes acute onset severe lameness, but clinical findings and diagnostic analgesia often fail to identify precisely the site of pain. Consistent radiographic changes suggested TO was contributing to the lameness and this diagnosis was supported by nuclear scintigraphy. The poor success of conservative treatment (including intra-articular medication) suggests that surgical arthrodesis is the treatment of choice, although the prognosis is still poor for a return to full soundness. POTENTIAL RELEVANCE: The clinical features described should facilitate more accurate diagnosis and prognosis. A novel surgical treatment is described which appears to offer significant improvement in the lameness. Further work is necessary to determine the causes of this condition and more effective management.     

Diagnostic evaluation and short-term outcome as indicators of long-term prognosis in horses with findings suggestive of inflammatory bowel disease treated with corticosteroids and anthelmintics

Background

Recurrent colic and unexplained weight loss despite good appetite and adequate feeding and management practices are common conditions in the horse. However, little information has been published on the systematic diagnostic evaluation, response to treatment, prognostic factors or outcome of either presentation. The aims of this study were to 1) identify possible prognostic indicators and 2) report the short- and long-term response to treatment with corticosteroid therapy of a variety of horses with a presumptive diagnosis of inflammatory bowel disease (IBD).Thirty-six horses with a history of recurrent colic and/or unexplained weight loss were screened with a detailed clinical, clinicopathological and diagnostic imaging examination. Twenty horses were subsequently selected that had findings consistent with inflammatory bowel disease based on the fulfilment of one or more of the following additional inclusion criteria: hypoproteinaemia, hypoalbuminaemia, malabsorption, an increased intestinal wall thickness on ultrasonographic examination or histopathological changes in rectal biopsy. These 20 horses were treated with a standardized larvicidal anthelmintic regime and a minimum of three weeks of corticosteroid therapy.

Results

The initial response to treatment was good in 75% (15/20) of horses, with a 3-year survival rate of 65% (13/20). The overall 3-year survival in horses that responded to initial treatment (12/15) was significantly higher (P = 0.031) than in those that did not respond to initial treatment (1/5). The peak xylose concentration was significantly (P = 0.048) higher in survivors (1.36 ± 0.44 mmol/L) than non-survivors (0.94 ± 0.36 mmol/L).

Conclusions

The overall prognosis for long-term survival in horses with a presumptive diagnosis of IBD appears to be fair to moderate, and the initial response to anthelmintic and corticosteroid therapy could be a useful prognostic indicator. The findings of the present study suggest that a low peak xylose concentration in absorption testing is associated with a less favourable prognosis, supporting the use of this test.     

Neodymium:yttrium-aluminum-garnet laser-assisted excision of progressive ethmoid hematomas in horses: 20 cases (1986-1996)

OBJECTIVE: To describe a technique of contact neodymium:yttrium-aluminum-garnet (Nd:YAG) laser-assisted excision of progressive ethmoid hematoma (PEH) in horses, to determine the recurrence rate of clinical signs of PEH in horses with follow-up time of a minimum of 12 months, and to compare this result with reported results achieved by using conventional techniques. DESIGN: Retrospective study. ANIMALS: 21 horses with 26 PEH. PROCEDURE: Medical records of all horses with PEH treated by Nd:YAG laser excision from December 1986 through August 1996 were analyzed. Twenty-one horses underwent unilateral (18 surgeries) or bilateral (14) frontonasal bone flap with excision of the mass, using an Nd:YAG laser. One horse with bilateral PEH underwent a unilateral bone flap twice, 1 year apart. RESULTS: 1 horse died. Four of 20 horses with followup times of 12 months or longer had recurrence of PEH. The PEH recurrence rate was 20% (5/25 PEH). Three of 6 horses with bilateral lesions had recurrence of PEH. Recurrence rate for horses that had bilateral PEH (3/6 horses) was greater than for horses with unilateral PEH (1/14 horses). CLINICAL IMPLICATIONS: Treatment of PEH by Nd:YAG laser excision through a frontonasal bone flap results in a recurrence rate comparable with that reported for conventional techniques. Horses with bilateral lesions are more likely to have a recurrence of PEH.     

Magnetic resonance imaging findings of bone marrow lesions in the equine distal tarsus

Three horses with sudden onset severe lameness were admitted for further diagnostic investigation. All horses had variable changes on radiographs in the distal tarsal region. Because of the sudden onset and severe degree of lameness, a magnetic resonance imaging (MRI) examination was performed. All horses showed areas of increased signal intensity in short tau inversion recovery (STIR) images involving the central and/or third tarsal bones. These lesions involved both the subchondral bone and bone marrow and are currently defined as bone marrow lesions (BML). Two horses were treated with shockwave therapy, one received intra‐articular medication. Two of the horses returned to previous athletic level and one is still in rehabilitation.     

Immunization with Trichophyton verrucosum Vaccine in Hunter/Jumper and Dressage Horses with Naturally Occurring Trichophyton equinum Infection: A Prospective,Randomized, Double-Blinded,Placebo-Controlled Clinical Trial

The aim of the current study was to investigate the efficacy of Trichophyton verrucosum vaccine in hunter/jumper and dressage horses with trichophytosis caused by Trichophyton equinum (cross immunity). A total of 25 hunter/jumper and dressage horses between the ages of 2 and 14 years, naturally infected with Trichophyton equinum, were enrolled and randomly assigned to either a placebo or an intramuscular lyophilized Trichophyton verrucosum vaccine group. Clinical evaluations were done by the same investigator, who scored clinical healing at the beginning, during, and at the end of the treatment and was blinded to allocation to the groups. At the end of the trial, vaccine treatment significantly decreased the investigator's clinical scores (P < .001), and no significant changes were detected in the placebo treatment group. In all of the horses vaccinated, the lesions improved gradually within 7 to 12 days after vaccination. Complete clinical remission was detected within 28 to 42 days, and all treated horses became culture negative within 25 days of starting treatment. No clinical healing was observed in nine untreated control horses throughout the study. No recurrence was observed in treated horses within 10 months after therapy. Results of the current study indicate that inactivated Trichophyton verrucosum vaccine may be a safe and effective therapy for horses with Trichophyton equinum infection.     

Effects of the ACE inhibitor quinapril on echocardiographic variables in horses with mitral valve insufficiency

Twenty horses with mitral valve insufficiency, but without signs of congestive heart failure, and five horses without signs of heart disease were examined before and after medication with an angiotensin-converting enzyme (ACE) inhibitor. The examination included echocardiography assessment as well as heart catheterization. The echocardiographic examination included B-mode, M-mode, conventional and colour Doppler techniques. For 8 weeks, all horses were treated with Accupro 20 (active substance: Quinapril) at an oral dose rate of 120 mg/horse/day. A follow-up of the horses with mitral valve insufficiency after 8 weeks revealed a statistically significant increase in the stroke volume and the cardiac output as well as a decrease in regurgitation velocity time integral (VTI). The regurgitation blood velocity remained the same. The severity of mitral valve insufficiencies revealed a moderate improvement in five horses, from moderate to mild, after therapy. Significant changes of cardiac dimension (B-mode) and shortening fraction (M-mode) before and after treatment could not be observed. The owners' judgement of the horses' performance was that of a minor improvement. In the horses without clinical findings the results of examination before and after treatment remained the same.     

Clinical effects of betamethasone and hyaluronan,and of defocalized carbon dioxide laser treatment on traumatic arthritis in the fetlock joints of horses

The clinical effects of intra-articular betamethasone together with hyaluronan (betaM/HA) and treatment with a defocalized carbon dioxide laser on acute traumatic arthritis of the fetlock joint were assessed. The horses in these studies were selected using a thorough lameness examination, including intra-articular anaesthesia abolishing the lameness. This investigation comprised an observer-blind study, including 10 sport horses (10 joints), and a prospective study, including 180 sport horses (333 joints). In both studies, the material was divided into two groups treated with either betaM/HA or a carbon dioxide laser. The treatment doses were 12 mg of betaM, 20 mg of HA or 60 J/cm2 of treated area. Convalescence before training was 21 days for both groups in the observer-blind study. In the prospective study, convalescence in the betaM/HA group was 21 days but was only 7 days for the laser-treated group. In the observer-blind study, three of five treated joints recovered in both cohorts. In the prospective study, the groups had significantly different recovery rates--68% of the betaM/HA-treated joints and 80% of the carbon dioxide laser-treated joints. These results indicate that the defocalized carbon dioxide laser should be an applicable mode of treatment of acute traumatic synovitis in horses. However, the biochemical functions related to carbon dioxide laser treatment require further elucidation.     

Septic arthritis in 15 standardbred racehorses after intra-articular injection.

Case histories, results of synovial fluid analyses, treatment regimens and outcome are described for 15 adult Standardbred horses with confirmed post-injection septic arthritis. Joint sepsis followed injection of corticosteroids, hyaluronic acid, polysulphated glycosaminoglycan, or local anaesthetic. The median interval from injection to appearance of clinical signs was 2.5 days, and median interval from injection to referral was 9 days. The median initial synovial leucocyte count on admission was 57 x 10(9)/litre, but there was a wide range of values (18-258 x 10(9)/litre). The median synovial neutrophil percentage was 95% (77-99%). All bacterial isolates were Gram-positive cocci, 86% of which were staphylococci. All treated horses (12/15) initially received broad-spectrum parenteral antibiotic therapy, and the articulations of all horses except one were lavaged, either with non-surgical through-and-through techniques only (N = 3), or surgically with arthrotomy (N = 1) or arthroscopy (N = 7). The owners of all treated horses were contacted and racing records were consulted. Eleven of 12 horses returned to racing. Outcome was judged as either satisfactory (3/12) if the horse had returned to racing levels similar to or better than before treatment, or unsatisfactory (9/12) if the horse had poorer performance or could not return to racing. The 3 horses with satisfactory follow-up had been treated with arthroscopy and post-surgical closed suction drainage. The results of bacterial cultures suggest that the initial antimicrobial agents used should be effective against penicillin-resistant staphylococci.     

Injection of corticosteroids, hyaluronate, and amikacin into the navicular bursa in horses with signs of navicular area pain unresponsive to other treatments: 25 cases (1999-2002)

OBJECTIVE: To determine history, clinical and radiographic abnormalities, and outcome in horses with signs of navicular area pain unresponsive to corrective shoeing and systemic nonsteroidal anti-inflammatory drug administration that were treated with an injection of corticosteroids, sodium hyaluronate, and amikacin into the navicular bursa. DESIGN: Retrospective study. ANIMALS: 25 horses. PROCEDURE: Data collected from the medical records included signalment, history, horse use, severity and duration of lameness, shoeing regimen, results of diagnostic anesthesia, radiographic abnormalities, and outcome. RESULTS: 17 horses had bilateral forelimb lameness, 7 had unilateral forelimb lameness, and 1 had unilateral hind limb lameness. Mean duration of lameness was 9.2 months. All horses had been treated with corrective shoeing and nonsteroidal anti-inflammatory drugs for at least 6 months; 18 had previously been treated by injection of corticosteroids and sodium hyaluronate into the distal interphalangeal joint. Fourteen horses had mismatched front feet, and 21 horses had signs of pain in response to application of pressure over the central aspect of the frog. Palmar digital nerve anesthesia resulted in substantial improvement in or resolution of the lameness in all horses. Twenty horses (80%) were sound and returned to intended activities 2 weeks after navicular bursa treatment; mean duration of soundness was 4.6 months. Two horses that received numerous navicular bursa injections had a rupture of the deep digital flexor tendon at the level of the pastern region. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that navicular bursa treatment may provide temporary improvement in horses with signs of chronic navicular area pain that fail to respond to other treatments.     

Treatment of equine cheek teeth by mechanical widening of diastemata in 60 horses (2000-2006)

REASON FOR PERFORMING STUDY: Cheek teeth (CT) diastemata are a significant cause of painful dental disease in horses and limited factual information is available on the treatment of this disorder. OBJECTIVE: To assess the response to mechanical widening in the treatment of diastema. METHOD: Details of the presenting signs and treatment of cases of CT diastema by widening were recorded and the response to treatment of these cases assessed by re-examinations and by obtaining follow-up information from owners. RESULTS: Sixty horses of various breeds, median age 9 years, with clinically significant CT diastemata were classified as having primary (inadequate rostro-caudal CT compression: n = 29) and secondary (to other dental abnormalities: n = 31) diastemata. Quidding was present in 82% of cases, weight loss in 35%, halitosis in 17% and bitting disorders in 12%; 85% of the identified CT diastemata involved mandibular CT and 15% maxillary CT, with caudal CT more commonly affected. Of 273 identified diastemata in the 60 horses, 207 were deemed to have significantly associated periodontal food pocketing and were widened to 4.5-5.5 mm diameter on their occlusal surface using a mechanical burr. The 29 horses with primary diastemata received a median of 1.3 treatments each and at 10 months following their last treatment 72% showed complete remission of signs and 28% showed good improvement. The 31 horses with secondary diastemata received a median of 2.2 treatments each and, at mean 9 months following their last treatment, 48% showed full improvement, 42% good improvement, 6% slight improvement and 3% no improvement. Inappropriate areas of the clinical crown were removed from 4 CT without causing pulpar exposure; one case was reported to have a transient oral infection post treatment and another developed an apical infection in a treated tooth that was unrelated to the diastema widening. CONCLUSION: Diastema widening is an effective treatment of periodontal pocketing in CT diastemata. POTENTIAL RELEVANCE: The described treatment of CT diastema widening by trained personnel is an effective and safe treatment, but repeated treatments are often necessary, especially with secondary diastemata.