Gastrojejunostomy as a treatment for gastric outflow disorders in four adult horses.

Four adult horses with histories of moderate abdominal pain and inappetence were diagnosed with delayed gastric emptying and gastric impaction attributed to pyloroduodenal obstruction (three cases) or duodenitis (one case). A stapled side-to-side gastrojejunostomy was performed on all horses. Two horses returned to work and survived ≥3 years. One horse was euthanased 6 months post-surgery due to recurrent abdominal pain, and one was found dead 5 months postsurgery after an unattended foaling.

Pharmacokinetics of ingenol mebutate gel under maximum use conditions in large treatment areas.

PURPOSE: Actinic keratoses (AKs) exist on a continuum with squamous cell carcinoma and can occur as sub-clinical and clinically visible lesions in cancerized fields on sun-damaged skin. Ingenol mebutate effectively treats AKs on areas up to 25 cm2, but actinic keratosis can affect larger areas of skin. This trial evaluated systemic exposure and safety of ingenol mebutate gel on larger areas of skin under maximum use conditions. METHODS: Phase I, multicenter, open-label, uncontrolled, non-randomized trial. Patients received ingenol mebutate gel for three consecutive days on approximately 250 cm2 of sun-damaged skin on the full face (0.027%), the scalp (0.027%), or arm (0.06%). RESULTS: Of 61 patients, 10 (face =8; arm =2) had ingenol mebutate in whole blood at subnanomolar levels (0.235-0.462 nM). The assayed metabolites were below the lower limit of quantification. Local skin responses increased during Days 1-4 and declined thereafter, approaching baseline by Day 16. Most adverse events were pain/pruritus of mild or moderate intensity. CONCLUSIONS: Subnanomolar systemic exposure to ingenol mebutate was measured after application of the gel to approximately 250 cm2 on the full face, scalp, or arm under maximum use conditions. No clinically relevant systemic adverse reactions were observed, and local skin responses were manageable.

Equine leptospirosis in tropical Northern Queensland.

OBJECTIVE: Determine leptospiral serodiversity, serodominant serovars and prevalence in the horse population of Northern Queensland (NQ), Australia, with special focus on the Atherton Tableland and Townsville-Burdekin regions. DESIGN: Cross-sectional survey. METHODS: Serum samples from 429 horses originating from 172 horse-owning properties in NQ were collected at regional horse shows and veterinary clinics. Samples were analysed using a microscopic agglutination test. Owners were interviewed on potential risk factors associated with leptospirosis. RESULTS: Of the 172 properties that submitted samples, horses from 60 properties (35%, 95% confidence interval (CI) 31-39%) in NQ showed evidence of exposure to one or more serovars of Leptospira at a serum dilution of 1 : 100. The proportion of seropositive properties in the Atherton Tableland and Townsville-Burdekin regions was 25% (95% CI 17-33%) and 36% (95% CI 30-43%), respectively. In total, 81 horses had titres to a single serovar and the remained had titres to two or more serovars. Although 20 serovars representing 17 serogroups were detected, serovar Arborea was serodominant and detected in horses from 29 properties. Geldings were more at risk (odds ratio 3.3) of being seropositive to serovar Arborea. The detection of serovar Arborea-seropositive horses was strongly associated (P < 0.05) with the average annual rainfall each property received and the presence of pigs and sugarcane fields in the vicinity. CONCLUSION: Serological evidence of leptospirosis in horses in NQ indicates that prevalence is high and horses have been exposed to a wide range of serovars.

Laboratory toxicity and benthic invertebrate field colonization of Upper Columbia River sediments: finding adverse effects using multiple lines of evidence.

From 1930 to 1995, the Upper Columbia River (UCR) of northeast Washington State received approximately 12 million metric tons of smelter slag and associated effluents from a large smelter facility located in Trail, British Columbia, approximately 10 km north of the United States-Canadian border. Studies conducted during the past two decades have demonstrated the presence of toxic concentrations of heavy metals in slag-based sandy sediments, including cadmium, copper, zinc, and lead in the UCR area as well as the downstream reservoir portion of Lake Roosevelt. We conducted standardized whole-sediment toxicity tests with the amphipod Hyalella azteca (28-day) and the midge Chironomus dilutus (10-day) on 11 samples, including both UCR and study-specific reference sediments. Metal concentrations in sediments were modeled for potential toxicity using three approaches: (1) probable effects quotients (PEQs) based on total recoverable metals (TRMs) and simultaneously extracted metals (SEMs); (2) SEMs corrected for acid-volatile sulfides (AVS; i.e., ∑SEM - AVS); and (3) ∑SEM - AVS normalized to the fractional organic carbon (f(oc)) (i.e., ∑SEM - AVS/f(oc)). The most highly metal-contaminated sample (∑PEQ(TRM) = 132; ∑PEQ(SEM) = 54; ∑SEM - AVS = 323; and ∑SEM - AVS/(foc) = 64,600 umol/g) from the UCR was dominated by weathered slag sediment particles and resulted in 80% mortality and 94% decrease in biomass of amphipods; in addition, this sample significantly decreased growth of midge by 10%. The traditional ∑AVS - SEM, uncorrected for organic carbon, was the most accurate approach for estimating the effects of metals in the UCR. Treatment of the toxic slag sediment with 20% Resinex SIR-300 metal-chelating resin significantly decreased the toxicity of the sample. Samples ∑SEM - AVS > 244 was not toxic to amphipods or midge in laboratory testing, indicating that this value may be an approximate threshold for effects in the UCR. In situ benthic invertebrate colonization studies in an experimental pond (8-week duration) indicated that two of the most metal-contaminated UCR sediments (dominated by high levels of sand-sized slag particles) exhibited decreased invertebrate colonization compared with sand-based reference sediments. Field-exposed SIR-300 resin samples also exhibited decreased invertebrate colonization numbers compared with reference materials, which may indicate behavioral avoidance of this material under field conditions. Multiple lines of evidence (analytical chemistry, laboratory toxicity, and field colonization results), along with findings from previous studies, indicate that high metal concentrations associated with slag-enriched sediments in the UCR are likely to adversely impact the growth and survival of native benthic invertebrate communities. Additional laboratory toxicity testing, refinement of the applications of sediment benchmarks for metal toxicity, and in situ benthic invertebrate studies will assist in better defining the spatial extent, temporal variations, and ecological impacts of metal-contaminated sediments in the UCR system.

Preliminary evaluation after setting up a post-assessment attention deficit hyperactivity disorder clinic in a community setting.

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a common neuro-behavioural condition affecting school age children, older adolescents and young adults. It often leads to challenging educational, social and personal difficulties and co-morbidities which makes it an appropriate focus for the setting up of a dedicated clinic. AIM: This service innovation was planned to ensure that ADHD patients receive regular multi-disciplinary reviews and to improve the training standards of junior doctors. We hypothesised that multimodal treatment approach shall be more acceptable to parents and children with ADHD than medication alone. It was our belief that the setting up of a post-assessment ADHD clinic will lead to efficient use of existing resources thereby saving clinical time. METHOD: Our local audit identified 51 young people with ADHD stabilised on medication. One year after setting up the post-assessment ADHD clinic, feedback was obtained using questionnaires from clinicians and parents. RESULTS: Seventy-five percent of parents and all the clinicians responded. Parents indicated that they were quite satisfied with the changes made. Clinicians were of the opinion that the dedicated ADHD clinic was more efficient in meeting the children's needs. CONCLUSION: This survey validated our hypothesis that multi-modal reviews were more acceptable to parents of children with ADHD. The setting up of the dedicated clinic proved to be an efficient way of using the existing resources without any additional costs.

Mechanical and functional properties of the equine superficial digital flexor tendon.

The in vitro and in vivo mechanical properties of the superficial digital flexor tendon have been described. To date the focus has been on single load to failure testing, however refined in vivo methods may prove useful to evaluate the effects of treatment and exercise on tendons. During maximal exercise, the adult superficial digital flexor tendon operates close to its functional limits with a narrow biomechanical safety margin. This combined with exercise and age associated microdamage, and a limited adaptive ability may increase the risk of fatigue failure. Studies evaluating treatment regimens for tendonitis have focused on repair and regeneration and yielded varying results. It would appear that the superficial digital flexor tendon has a limited ability if any to adapt positively to exercise after maturity. In contrast, the foal's superficial digital flexor tendon may have a greater adaptive ability and may respond to an appropriate exercise regimen to produce a more functionally adapted tendon. Recent studies have shown that foals allowed free pasture exercise develop a larger, stronger, more elastic tendon compared to foals that were confined or subjected to a training program. Effects on the non-collagenous matrix appear to be responsible for these differences. In contrast, training or excess exercise may have permanent detrimental effects on the biomechanical and functional properties of the superficial digital flexor tendon in the foal. The implication is that the determination of optimum exercise intensity and timing, and the role of the non-collagenous matrix in tendon physiology in the young horse may hold the key to developing tendons more capable of resisting injury.

Treatment of long bone fractures in South American camelids: 5 cases.

An adult llama and four alpacas were referred with long bone fractures. The llama presented with a closed, comminuted fracture of the right metatarsal bones. Two of the alpacas presented with comminuted fractures of the proximal radius. One fracture was closed and one was open. One alpaca had a closed, comminuted fracture of the distal radius, and the final alpaca had a closed, oblique fracture of the metatarsus. A diagnosis was made in each animal on the basis of clinical examination and radiographs. All fractures were managed by open reduction and internal fixation using selective placement of lag screws and dynamic compression plates. Four animals made uneventful recoveries and no long-term complications were encountered. One alpaca was re-admitted for plate failure and non-union of the fracture 5 weeks after surgery. The plate and screws were removed and a transfixation cast was applied. The fracture healed, however the alpaca showed signs of radial nerve paralysis after the cast was removed. With confinement in a small yard, full function gradually returned to the leg over the ensuing 4 months. Using techniques recommended in other species, South American camelids are suitable candidates for long bone fracture repair using open reduction and internal fixation.

Recent advances in equine abdominal surgery.

Laparoscopy is a minimally invasive procedure that has applications as a diagnostic, therapeutic and prognostic technique. Specialized equipment is necessary to perform equine laparoscopy, and there is a large range of instruments, both disposable and non-disposable available. Laparoscopic procedures described include ovariectomy, cryptorchidectomy, adhesiolysis and herniorrhaphy. Laparoscopy can be performed in a standing or dorsally recumbent position, depending on surgeon preference, patient status and the procedure to be performed. Stapling equipment is frequently used in gastrointestinal surgery in horses. Advantages include decreased surgical time and a decrease in the risk of contamination. Stapling equipment is often used in creating anastomoses, both in the large and small intestines, as well as in vessel ligation. New surgical techniques intended to decrease adhesion formation include the use of carboxymethylcellulose and bioresorbable patches. Indwelling abdominal drains can be used for peritoneal lavage following surgery and also appear to decrease the risk of adhesion formation. Improvements in post-operative care, including the treatment of post-operative ileus and endotoxaemia can significantly improve the outcome of horses that have undergone surgery for abdominal disorders. Recommendations for the use of prokinetic agents in horses with ileus vary widely. Prokinetic agents include local anaesthetics, macrolide antimicrobials, cholinergic agonists and dopamine antagonists. Endotoxaemia is common in horses following surgery for gastrointestinal disorders. The antibiotic polymyxin B binds to the circulating endotoxin molecule, decreasing its half-life in the intra-vascular space and reducing associated inflammation. This drug appears to be an effective and affordable treatment option for horses with endotoxaemia. The use of specific cyclooxygenase inhibitors in veterinary medicine have been studied recently. Selective cyclooxygenase-2 inhibitors may provide comparable anti-inflammatory and analgesic properties to the non-selective non-steroidal anti-inflammatory drugs. These drugs appear to have similar clinical effectiveness and will hopefully minimize deleterious side effects. The optimal healing of ventral midline incisions in horses is related to many factors including appropriate suture patterns and bite size, in addition to appropriate post-operative exercise recommendations. Recent advances in surgical techniques and post-operative care should decrease the morbidity and mortality associated with abdominal surgery. This article provides an overview of some of these advances.

Surgical repair of a cleft soft palate in an alpaca.

A 26-day-old entire male alpaca was referred for surgical treatment of a cleft soft palate. Mandibular symphysiotomy and three-layer closure of the palatal defect resulted in primary intention healing. Despite complications related to anaesthesia the alpaca made a full recovery.

Chemical arthrodesis of the distal tarsal joints using sodium monoiodoacetate in 104 horses.

OBJECTIVE: To evaluate chemical arthrodesis using sodium monoiodoacetate for treatment of degenerative joint disease of the tarsometatarsal and distal intertarsal joints. DESIGN: Retrospective clinical study. METHOD: Horses were diagnosed with degenerative joint disease of one or more of the tarsometatarsal or distal intertarsal joints based on history, lameness examination, radiographic findings and, in some cases, response to intra-articular anaesthesia or medication. Intra-articular injections of sodium monoiodoacetate were performed using 23 gauge needles in the sedated, standing horse. Positive contrast arthrography of the distal intertarsal joint was performed in all horses to evaluate needle placement and the presence or absence of communication with other synovial structures. The mean intra-articular dose of sodium monoiodoacetate was 192 mg. Horses were subject to a graded exercise program commencing 7 to 10 days after treatment. Where possible, follow up lameness examination and radiography was performed at 3, 6, 12 and 24 months after treatment. RESULTS: At 3, 6, 12 and 24 months after treatment, respectively, 0/57, 14/55, 41/50, and 29/34 of horses were sound. At 3, 6, 12 and 24 months after treatment, respectively, 5/55, 24/38, 26/30 and 18/18 of horses had radiographic evidence of ankylosis of treated joints. Post injection pain was marked in 6.7% of horses and significant complications requiring further treatment occurred in 3.8% of horses. CONCLUSIONS: Chemical arthrodesis using sodium monoiodoacetate was an effective treatment method for degenerative joint disease of the distal tarsal joints. The technique was performed in the sedated standing horse and required minimal equipment. Results were comparable to those achieved following surgical arthrodesis. The risk of significant complications was minimised through good technique using an appropriate injection volume and concentration.

Unilateral nephrectomy as a treatment for renal trauma in a foal.

A 2-day-old Warmblood colt foal was referred for evaluation of progressive abdominal distension and lethargy. Haemoperitoneum was diagnosed and a ventral midline laparotomy revealed capsular rupture, sub capsular haematoma and haemorrhage of the left kidney. Unilateral nephrectomy was performed and the foal recovered uneventfully, with no reported complications 1 year later.

Recombinant equine growth hormone administration: effects on synovial fluid biomarkers and cartilage metabolism in horses.

REASONS FOR PERFORMING STUDY: Recombinant equine growth hormone (reGH) has recently been evaluated for effects on body condition and wound healing. It has the potential to influence articular cartilage via stimulation of IGF-1. OBJECTIVES: To investigate effects of administration on synovial joint metabolism. METHODS: Six mature horses were given 20 microg/kg bwt reGH daily for 8 weeks by i.m. injection. Three control horses were injected with sterile water. Serum and synovial fluid samples were collected at 6, 8, 11 and 16 weeks for GH and IGF-1 assays. Articular cartilage harvested at week 16 was evaluated by Western analysis using monoclonal antibodies BC-13, BC-4, 8-A-4 and CH-3. RESULTS: Concentrations of IGF-1 in serum and synovial fluid were significantly elevated (P < 0.05) at 6 and 8 weeks in the reGH group. Glycosaminoglycan concentrations in synovial fluid were significantly less than controls at these time points, suggesting that reGH may modulate proteoglycan metabolism in articular cartilage. In the reGH group, there were not any alterations in synovial fluid content of 3B3(-) epitope or aggrecan metabolite, or in aggrecan or link protein catabolites retained within cartilage, that might be expected with development of osteoarthritis. CONCLUSIONS: Intramuscular administration of reGH may be a more efficient means of delivery of IGF-1 to joints for cartilage resurfacing initiatives. POTENTIAL RELEVANCE: We found no alterations in cartilage metabolism indicative of development of osteoarthritis.

Catheters: a review of the selection, utilisation and complications of catheters for peripheral venous access.

Intravenous catheters are used for the administration of medications and fluids and are an integral part of veterinary practice. The aim of catheter use is to optimise administration of medication and minimise complications such as thrombus formation, thrombophlebitis and sepsis. Catheters made from teflon are less flexible, less durable and stimulate more tissue reaction than polyurethane or silicon. However silicon catheters are more expensive and complicated to insert. Generally, for veterinary practice, the biostability and cost of polyurethane catheters make them preferable for short and long-term use. The smallest diameter catheter should be selected to minimise internal vessel wall contact and irritation without compromising medication delivery. The site of insertion varies with individual preference, vessel access and patient compliance. The jugular, cephalic, saphenous, ear, lateral thoracic and subcutaneous abdominal veins are accessible. Hair removal and a thorough aseptic skin preparation should be performed prior to catheter insertion. Daily maintenance is required to detect complications and maximise catheter longevity. Potential complications include thrombus formation, thromboembolism, bacterial colonisation and septicaemia, blood loss and air embolism. Permanent or transient skin dwelling bacteria are commonly isolated if sepsis occurs. The development of novel antiseptic and antibiotic impregnated catheters may reduce the complications associated with catheter infection in the future.

Suture materials: composition and applications in veternary wound repair.

Suture materials play an important role in veterinary surgery by providing support for healing tissues during wound repair. As there is no single ideal suture material, clinicians must compromise on some properties when selecting a material for a specific purpose. By reviewing the characteristics of absorbable and non-absorbable materials, general recommendations can be made on their usage in skin, fascia, viscera and other tissues.

Results of surgical treatment of colic in miniature breed horses: 11 cases.

OBJECTIVE: To report on the outcome of surgical treatment of acute abdominal crises in miniature breed horses. DESIGN: Retrospective case series of miniature horses presented to the University Veterinary Centre, Camden with an acute abdominal crisis. METHODS: Hospital records of all miniature horses that underwent ventral midline laparotomy for acute abdominal crisis between 1997 and 2001 were reviewed. The signalment, history, clinical signs, results of ancillary diagnostic procedures, location and type of intestinal lesion, treatment and outcome were retrieved from each case record. Long-term survival was determined by telephone interview of owners. RESULTS: Eleven miniature horses including five females and six males underwent ventral midline laparotomies for acute abdominal crisis during the study period. Ages ranged between 1 month and 19 years. Surgical findings included faecalith obstruction (seven horses), enterolith (one horse), strangulating lipoma of the descending colon (one horse), jejunal infarction (one horse), and caecal infarction (one horse). Long-term survival rate (minimum 12 months post surgery) was 55%. Six of eight horses with simple intraluminal obstructions survived, while the three horses with gastrointestinal lesions associated with vascular compromise were euthanased either at surgery (caecal infarction), or postoperatively, due to complications (strangulating lipoma of the descending colon, jejunal infarction). Postoperative complications in this study included impaction of the descending colon (two horses), diarrhoea (two horses), peritonitis (one horse), hyperlipaemia (two horses), incisional infection (two horses) and abdominal adhesions (one horse). Hyperlipidaemia was present in five of seven horses in which serum triglycerides were measured at presentation. CONCLUSIONS: Simple intraluminal obstructions of the large intestine were frequently encountered during exploratory laparotomy in miniature horses presented for acute abdominal crises, and their surgical treatment was associated with a good prognosis. In contrast, this study suggested that abdominal pain associated with vascular compromise of gastrointestinal tissues in miniature horses was associated with a poorer prognosis, consistent with reports in other horse breeds. Possible contributing factors to faecalith formation, including poor quality roughage, dental disease, and inadequate water consumption, should be recognised and avoided in miniature horses. Serum triglyceride concentrations should be measured in miniature horses presented for acute abdominal pain. If elevated, nutritional supplementation should be provided.

Palmar digital neurectomy in 24 horses using the guillotine technique.

OBJECTIVE: To determine the effectiveness and incidence of complications of palmar digital neurectomy using the guillotine technique in horses presented for lameness originating from sites innervated by these nerves. DESIGN: Retrospective study of 24 clinical cases. ANIMALS: Twenty-four horses undergoing a palmar digital nerve neurectomy between June 1997 and June 2001. METHODS: The records of all horses undergoing a uniaxial or biaxial, unilateral or bilateral neurectomy during the defined time period were retrieved. Information retrieved from the record included breed, age, gender, discipline for which the horse was used, history, results of lameness examination, results of perineural anaesthesia, radiographic findings, surgery report, postoperative care, complications and outcome. RESULTS: Seventeen geldings and seven female horses of mixed breeds, ranging in age from 1 to 16 years, that were used for a variety of non-racing, but competitive, athletic disciplines, underwent neurectomy using the guillotine technique during the specified time period. In 23 horses perineural anaesthesia was performed at the University Veterinary Centre to isolate the lameness. Anaesthesia resolved lameness in 18 horses. In five horses there was some residual lameness isolated to sites remote from the distal extremity. The most common radiographic finding was an increase in the number and or size of the synovial fossae of the navicular bone. Twenty-two horses underwent bilateral biaxial neurectomies and two horses with painful trauma-induced neuromas underwent unilateral, uniaxial neurectomy. There were no postoperative complications. All horses were rested for 3 months before returning to work. At least 1 year after surgery, 22 horses were in full work and two horses were not in work because of unrelated problems. Of the horses in work, 17 were considered free of lameness. The other five were competing, but receiving medication for residual lameness associated with sites remote from the distal extremity. CONCLUSION: Results of this study suggested that palmar digital neurectomy using the guillotine technique provided reliable and consistent resolution of lameness originating from sites innervated by these nerves. There were no significant complications.

Correlation of cartilage oligomeric matrix protein (COMP) levels in equine tendon with mechanical properties: a proposed role for COMP in determining function-specific mechanical characteristics of locomotor tendons.

Over-strain injury of the superficial digital flexor tendon (SDFT) is a common injury in the horse. Tendon appears to adapt to loads placed on it during development, but fatigue damage accumulates after skeletal maturity, which is inadequately repaired and predisposes to clinical tendinitis. In any population of horses, there is a wide variation in SDFT mechanical properties. A noncollagenous protein, cartilage oligomeric matrix protein (COMP), is particularly abundant during growth in the equine SDFT and has been proposed to have an organisational role in the formation of collagenous matrices. This study aimed to determine whether COMP levels were correlated to mechanical properties at skeletal maturity. Tendons from 2 groups of 12 horses were analysed: Group 1 horses with restricted age, 2 years +/- 2 months, showed a significant correlation between both ultimate tensile stress modulus of elasticity and stiffness and COMP, while Group 2 mature horses with varying age did not, because of age- and exercise-induced loss of COMP. These data supports the hypothesis that COMP is an important mediator in the growth of tendon. This data would suggest that the identification of low COMP levels in tendon during growth would indicate horses prone to tendon injury and methods of promoting COMP synthesis during growth would potentially improve tendon quality and reduce the risk of subsequent tendinitis.

Conservative management of minimally displaced radial fractures in three horses.

Minimally displaced, spiral, radial fractures were diagnosed in three adult horses. Two horses had open fractures and in one horse the fracture was closed. A diagnosis was made on radiographs taken 24 h, 5, and 9 days after the fracture. There was minimal displacement of the fracture fragments despite the considerable time which had elapsed between fracture and diagnosis and an unfavourable prognosis with internal fixation, so conservative therapy was the preferred method of treatment. One horse developed a sequestrum and draining sinus, which was treated surgically under general anaesthesia 3 months after diagnosis of the fracture. Other complications were minimal and transient. Two horses were being used for pleasure riding 12 months after fracture and one horse was pasture sound at 8 months.