Use of multi‐detector computed tomographic angiography in the diagnosis of a parapharyngeal aneurysm in a 6‐week‐old foal

Multidetector‐row computed tomographic contrast angiography (MDCTA) is routinely employed to investigate vascular masses in human patients but, to date, the use of this technique to investigate an aneurysmal mass has not been reported in an equine case. The potential of MDCTA to investigate a right‐sided parapharyngeal mass in a 6‐week‐old Thoroughbred foal was therefore investigated. A 4‐slice helical computed tomography scanner was used on a superficial, firm, ovoid mass yielding arterial blood on fine needle aspiration. MDCTA enabled identification of the vessels involved thus assisting in forming a diagnosis based on the morphology of the lesion and aided surgical planning. Histology confirmed the presence of mural thrombus and calcification within the smooth muscle wall consistent with a true aneurysm. MDCTA provided additional information to conventional imaging in this case of vascular masses of the head and neck. The technique therefore has the potential to improve diagnosis and assist in the management of such lesions.     

Diagnosis and treatment of biaxial keratomas in the left fore foot of a 15‐year‐old Clydesdale mare

A 15‐year‐old Clydesdale mare presented for further diagnostics and treatment of waxing and waning lameness and recurrent subsolar abscesses. Radiographs and computed tomography revealed biaxial masses extending from the hoof capsule, causing bone resorption of the distal phalanx. Surgery was performed to remove the masses and post operative care included regional limb perfusions, systemic antibiotics and therapeutic shoeing. Histopathology was consistent with the diagnosis of keratoma for each of the masses; this is the first case of confirmed biaxial keratomas. Two months after surgery the horse is sound at the walk and is expected to return to full function within the next year.     

Diagnosis of Borrelia‐associated uveitis in two horses

Borrelia burgdorferi, the etiologic agent of Lyme disease is a tick born spirochetal infection. Clinical signs of Lyme borreliosis are uncommon in horses, but when present they are often vague and nonspecific. In horses, Lyme borreliosis has been implicated in musculoskeletal, neurological, reproductive, and ocular disorders, including uveitis, but definitive diagnosis can be challenging as the causative agent is rarely isolated and serologic tests can be unreliable and do not confirm active disease. Here, we report two cases of equine uveitis associated with B. burgdorferi based on the identification of spirochetes within ocular fluids and confirmed with PCR testing. The two cases illustrate some of the challenges encountered in the recognition and diagnosis of equine Lyme borreliosis. Although only one of many possible causes of equine uveitis, Lyme disease should be considered a differential diagnosis, especially in endemic areas. Given the possibility for false negative results of serum tests during uveitis associated with B. burgdorferi and the failure of such tests to confirm active infection, a combination of cytologic assessment, antibody, and/or PCR testing of ocular fluids may be worthwhile if the clinical suspicion for Lyme uveitis is high.     

Clinical progress in the diagnosis of thoracolumbar problems in horses

It is well known that a painful back can be responsible for loss of performance in horses. Veterinary examination of the sore back used to be limited to manual palpation with diagnosis confirmed empirically by response to treatment. Today, due to advances in imaging, there are multiple methods for evaluating the pathology of the horse's thoracolumbar (TL) spine. Radiography, ultrasonography, nuclear scintigraphy, thermography and algometry all play a part in developing a better understanding of equine TL problems. Despite this progress, definitive diagnosis can still be problematic. There is a lack of objectivity in understanding the implications of the pathology detected and its effect on the horse. It is difficult to determine the degree of pain experienced by individual horses and how that interferes with their performance and welfare. This paper emphasises the importance of a systematic clinical examination to identify the presence of pain that can be supported by recognition of pathology using a range of diagnostic aids. These will also be reviewed to assist the clinician in understanding the tools available to evaluate a horse with a sore back.     

Diagnostic and prognostic use of L‐lactate measurement in equine practice

Lactate concentrations can now be measured rapidly and inexpensively in equine hospitals or in the field with a degree of accuracy that is acceptable when compared to laboratory analysers. Arterial or venous blood samples can be used. Short‐term storage of samples for up to 4 h at room temperature does not appear to affect the result. Taking a sample in the field and returning to the practice to analyse it is therefore feasible. Lactate measurement is useful in horses with colic to aid in the diagnosis of an ischaemic lesion and to determine the probability of a successful outcome if surgery is undertaken. Lactate concentrations are also useful as an indicator of hypoxia and/or circulatory disturbances associated with intra‐, or post partum abnormalities including dystocia, prematurity, dysmaturity, neonatal encephalopathy, sepsis, systemic inflammatory response syndrome or enteritis. Measuring lactate concentrations may assist in determining the severity of these conditions and the need for intensive care. Initial lactate concentration and increases or decreases in blood lactate concentration following a period of treatment can provide useful prognostic information. Lactate may also be measured during training to monitor fitness and performance.     

Principles for ethical treatment decision‐making in veterinary oncology

Many owners of companion animals with cancer are overwhelmed by having to choose the “right course of action.” With the aim of reducing the burden on owners who are forced to act as surrogates for their animals, this work discusses principles that apply to ethical treatment decision‐making for animal patients with cancer. Four principles frequently used for ethical decision‐making in human medicine will be considered for their potential applicability in veterinary medicine. As a result of these considerations, preliminary guidelines are presented, along which a decision‐making discussion can be held. The deliberate integration of the non‐maleficence and beneficence principles into the purely empirical facts of what is medically possible helps to maintain a moral perspective in specialized veterinary medicine. At the same time, such guidelines may contribute to individual decision‐making in a way that animal patients neither have to endure unnecessarily severe side effects, nor that they are euthanized prematurely.     

Cerebellar abiotrophy in a 6‐year‐old Arabian mare

Cerebellar abiotrophy (CA) is an uncommon neurological disease that most commonly affects Arabian horses. Affected horses are typically identified within the first 6 months of life. Intention tremor, wide based stance and ataxia are common clinical signs observed in affected individuals. No treatment is available for resolution of clinical signs. Definitive diagnosis is based on histopathological examination of cerebellar tissue, which is characterised by loss of Purkinje cell layer. This report describes a case of cerebellar abiotrophy that had a delayed diagnosis until 6 years of age.     

Clinical evaluation of a jejunojejunal end‐to‐end anastomosis with skin staples with or without coverage by a mesenteric flap

This study describes a novel end‐to‐end‐jejunojejunal‐anastomotic technique using skin staples following resection of compromised small intestine. Five horses were referred with colic and underwent exploratory laparotomy, resection and anastomosis. No long‐term complications were recorded at 12 months. This safe and effective technique may be used in equine gastrointestinal surgery.     

Caecal duplication in a 13‐year‐old Thoroughbred

A 13‐year‐old Thoroughbred gelding was presented for evaluation of recurrent colic of 4 weeks duration. These colic episodes were mild and responsive to medical therapy. Episodes of colic became more frequent and more painful. Exploratory laparotomy revealed a large intestine duplication with a cystic structure located at the caecocolic junction that was unable to be exteriorized and therefore not amenable to surgical correction. Thirty‐six hours following surgery, the horse became acutely painful, sweaty, and febrile suggesting gastrointestinal rupture. Post mortem examination showed a 0.6 × 1 m duplication and a 0.5 × 0.6 m cystic dilation that was probably associated with the caecum. There was a 10 × 30 cm area of rupture located within the duplication. Histological evaluation confirmed the presence of a true duplication.     

Laparoscopic‐assisted diagnosis of anomalous unilateral abdominal cryptorchidism

This report describes an unusual case of unilateral abdominal cryptorchidism in a Shetland pony. On the cryptorchid side, no testicular structures were present in the inguinal area but testicular/epididymal remnants at the distal end of a pedunculated structure could be discerned in the abdomen at laparoscopic examination. Furthermore, the deferent duct was disconnected from the epididymal remnants and the deferent duct was visible at the caudal aspect of the bladder, traversing over the lateral ligament of the bladder into the vaginal ring where it ended blindly in the vaginal process. After laparoscopic removal of the testicular/epididymal remnants and castration of the contralateral normally descended testicle, the hCG stimulation test was negative and the pony no longer exhibited masculine behaviour.     

Resolution of hypertrophic osteopathy in a 2‐year‐old filly

This article reports the successful management of a 2‐year‐old Thoroughbred filly that presented with clinical signs of hypertrophic osteopathy, diffuse granulomatous dermatitis, lethargy and inappetence. An infectious primary focus was suspected due to an elevated white blood cell count (WBC), marked neutrophilia and dramatically increased serum amyloid A (SAA) and plasma fibrinogen levels. After failure to respond to a range of antimicrobial treatments, an actinomycetes bacterial infection, such as Mycobacterium avium or Rhodococcus equi, was suspected and the horse was started on rifampicin and clarithromycin treatment, which resulted in a rapid and pronounced improvement in clinical signs. After 10 weeks of treatment the skeletal manifestations had regressed, both clinically and radiographically, in addition to normalisation of the WBC count, SAA and fibrinogen levels.     

Pseudo‐polydactyly in a horse

A 14‐month‐old half‐breed horse showed a severe lameness due to a lesion of the right forefoot which appeared completely and asymmetrically cleaved, from the solar margin to the coronary band. The horse was presented to an abattoir for slaughter and both forelimbs were collected for diagnostic investigations. The hoof lesion described herein does not fulfil the diagnostic criteria of equine polydactyly since post mortem imaging and pathological investigations ruled out the presence of supernumerary digits. Based on the clinical signs, diagnostic imaging (computed tomography) and gross examination, a diagnosis of pseudo‐polydactyly was proposed. To the best of our knowledge, the features of the present case report are unique, thus widening the range of lesions observed at the level of the hoof, which is crucial for horse health and activity.     

Inter‐ and intra‐rater reliability and agreement in determining subcutaneous tumour margins in dogs

The objective of this prospective study was to evaluate agreement and reliability of calliper‐based measurements of locally invasive subcutaneous malignant tumours in dogs. Four raters measured the longest diameter of 12 subcutaneous tumours (7 soft tissue sarcomas and 5 mast cell tumours) from 11 client‐owned dogs during 3 randomized, blinded measurement trials, both pre‐ and post‐sedation. Inter‐ and intra‐rater reliability was evaluated using intra‐class correlation coefficient (ICC) and agreement was evaluated using Bland‐Altman plots. Inter‐ and intra‐rater reliability was good (ICC range of 0.8694‐0.89520) and excellent (ICC range of 0.9720‐0.9966), respectively. For agreement calculations, an a priori clinically relevant limit of agreement of 10 mm was set. Inter‐ and intra‐rater agreement was unacceptable with inter‐rater limits of agreement ranging from 15.9 to 55.6 mm and intra‐rater limit of agreement ranging from 11.9 to 28.1 mm. Review of the measurement trial photographs revealed that calliper orientation changes were frequent, occurring in 9/12 (75%) and 8/12 (67%) pre‐ and post‐sedation cases. No significant correlation was found between inter‐rater measurement standard deviations and calliper orientation changes or dog body condition score. These findings suggest veterinarians may have poor agreement in determining the gross edge of tumours, which is expected to introduce bias and inconsistency in tumour staging, assessing response to therapy, and surgical margin planning. Due to the potential consequences for veterinary cancer patients, future studies are needed to validate the present findings.     

Infertility in a mare with a chronic uterine tear,diagnosis and successful standing hand‐assisted laparoscopic repair

Uterine rupture is a well recognised and potentially fatal complication in the peripartum broodmare. This case report describes a 16 month history of infertility as the sole clinical sign in a Thoroughbred mare, subsequently diagnosed with a full thickness uterine tear. The clinical course, standing laparoscopically assisted repair and outcome are discussed.     

A 90‐day adaptation to a high glycaemic diet alters postprandial lipid metabolism in non‐obese horses without affecting peripheral insulin sensitivity

High glycaemic feeds are associated with the development of insulin resistance in horses. However, studies that evaluated the effect of high glycaemic feeds used horses that either ranged in body condition from lean to obese or were fed to increase body condition over a period of months; thus, the ability of high glycaemic feeds to induce insulin resistance in lean horses has not been determined. This study evaluated the insulin sensitivity of 18 lean horses fed a 10% (LO; n = 6), 20% (MED; n = 6) or 60% (HI; n = 6) non‐structural carbohydrate complementary feed for 90 days. Although both the MED and HI diets increased insulinaemic responses to concentrate feeding in relation to the LO diet (p > 0.05), neither induced insulin resistance, as assessed by glucose tolerance test, following the 90‐day feeding trial. Interestingly, the post‐feeding suppression of plasma non‐esterified fatty acids was less pronounced in HI‐fed horses (p = 0.054) on days 30 and 90 of the study, potentially indicating that insulin‐induced suppression of adipose tissue lipolysis was reduced. As insulin‐resistant animals often have elevated plasma lipid concentrations, it is possible that altered lipid metabolism is an early event in the development of insulin resistance. The effects of high glycaemic feeds that are fed for a longer duration of time, on glucose and lipid metabolism, should be investigated further.