Right dorsal colitis in horses: A multicenter retrospective study of 35 cases.

Background: Right dorsal colitis (RDC) is a nonsteroidal anti-inflammatory drug (NSAID) induced, protein losing enteropathy in horses associated with a high case fatality rate.

Objectives: To describe signalment, NSAID usage, clinical presentations, clinical pathology, ultrasonographic findings, treatments, outcomes, and factors associated with survival in horses diagnosed with RDC.

Animals: Thirty-five horses from 7 Australian equine hospitals diagnosed with RDC.

Distribution in Equine Lymphoid and Neural Tissues 70 Days Post Infection.

Equid herpesvirus-1 (EHV-1) causes respiratory disease, abortion and myeloencephalopathy in horses worldwide. As member of the , latency is key to EHV-1 epidemiology. EHV-1 latent infection has been detected in the trigeminal ganglion (TG), respiratory associated lymphoid tissue (RALT) and peripheral blood mononuclear cells (PBMC) but additional locations are likely.

Plasma amino acid concentrations during experimental hyperinsulinemia in 2 laminitis models.

Background: Endocrinopathic laminitis develops in association with insulin dysregulation, but the role of insulin in the pathogenesis remains unclear. Hyperinsulinemia can cause hypoaminoacidemia, which is associated with integumentary lesions in other species and therefore warrants investigation as a potential mechanism in laminitis.

Objective: Evaluate plasma amino acid concentrations in the euglycemic-hyperinsulinemic clamp (EHC) and prolonged glucose infusion (PGI) laminitis models.

Clinical implications of using adrenocorticotropic hormone diagnostic cutoffs or reference intervals to diagnose pituitary pars intermedia dysfunction in mature horses.

Background: Diagnosis of pituitary pars intermedia dysfunction (PPID) is problematic because of large variations in ACTH concentrations.

Hypothesis/objectives: Compare the test characteristics of baseline and post-thyrotropin-releasing hormone (TRH) stimulation plasma ACTH concentrations in horses using diagnostic cutoff values (DCOVs) and reference intervals (RIs) and determine the clinical consequences of using each method.

Animals: One hundred six mature horses: 72 control cases and 34 PPID cases.

Cumulative antibiogram and multidrug-resistant organisms in a regional equine referral hospital.

Prudent use of antimicrobials is paramount to slow the development of resistance and for successful treatment. The use of cumulative antibiograms will allow evidence-based antimicrobial selection with consideration of local resistance patterns. We generated a "first-isolate-per-patient" cumulative antibiogram for a regional equine referral hospital.

Effects of an anti-IGF-1 receptor monoclonal antibody on laminitis induced by prolonged hyperinsulinaemia in Standardbred horses.

Currently, there are no registered veterinary drugs for the treatment of endocrinopathic equine laminitis, and although this form of the disease is known to be caused by prolonged hyperinsulinaemia, the mechanism of insulin toxicity is unclear. One possibility is that high concentrations of insulin activate IGF-1 receptors (IGF-1R) in lamellar tissue, leading to uncontrolled cell proliferation and epidermal lamellar dysregulation. An equinized version of a human anti-IGF-1R therapeutic monoclonal antibody (mAb11) was generated to test this theory, using a modification of the prolonged euglycaemic-hyperinsulinaemic clamp technique.

Lamellar perfusion and energy metabolism in a preferential weight bearing model.

Background: Supporting limb laminitis (SLL) is suspected to be caused by lamellar ischaemia as a consequence of increased mechanical load.

Objectives: Examine the effects of prolonged preferential weight bearing (PWB) on lamellar perfusion and metabolism.

Study Design: In vivo experiment.

Serum Amyloid A (SAA) Concentration after Vaccination in Horses and Mules.

Serum amyloid A (SAA) is a sensitive acute-phase response (APR) marker in equids. Prominent APRs with elevations of SAA concentrations ([SAA]) have been reported after vaccination. The authors hypothesized that vaccination with an inactivated EHV-1/-4 vaccine would cause increase in [SAA] and antibody responses and that higher [SAA] would be positively correlated with the antibody titer in both equids.

Effect of digital hypothermia on lamellar inflammatory signaling in the euglycemic hyperinsulinemic clamp laminitis model.

Background: Continuous digital hypothermia (CDH) prevents lamellar failure in the euglycemic hyperinsulinemic clamp (EHC) model of laminitis, but the protective mechanisms are unclear.

Hypothesis/objectives: To determine if CDH inhibits lamellar inflammatory signaling in the EHC model of laminitis.

Animals: Eight Standardbred horses.

Rhinosinusitis in an Australian mare caused by , a recently recognized invasive fungal pathogen of the horse.

We describe herein the clinical, endoscopic, computed tomography (CT), pathologic, and microbiologic features of an infection caused by an under-recognized fungal pathogen, , in a 25-y-old Australian Quarter Horse. The horse had a unilateral obstructive nasal mass, resulting in stertor and dyspnea. On endoscopy, the mass was tan, multinodular, and completely obstructed the nasal passage.

Lamellar energy metabolism and perfusion in the euglycaemic hyperinsulinaemic clamp model of equine laminitis.

Background: Hyperinsulinaemia is associated with the development of endocrinopathic laminitis; however, the mechanisms remain unclear.

Objectives: Evaluate the effects of hyperinsulinaemia on lamellar energy metabolism and perfusion during laminitis development.

Study Design: In vivo experiment.

The effect of continuous digital hypothermia on lamellar energy metabolism and perfusion during laminitis development in two experimental models.

Background: Continuous digital hypothermia (CDH) prevents lamellar failure in the euglycaemic hyperinsulinaemic clamp (EHC) and oligofructose (OF) laminitis models, but the mechanisms remain unclear.

Objectives: To evaluate the effects of CDH on lamellar energy metabolism and perfusion in healthy horses and during EHC and OF laminitis models.

Study Design: In vivo experiment.

Intraosseous infusion of the distal phalanx compared to systemic intravenous infusion for marimastat delivery to equine lamellar tissue.

No validated laminitis drug therapy exists, yet pharmaceutical agents with potential for laminitis prevention have been identified. Many of these are impractical for systemic administration but may be effective if administered locally. This study compared intraosseous infusion of the distal phalanx (IOIDP) with systemic intravenous constant rate infusion (CRI) to determine which was more effective for lamellar marimastat delivery.

Ultrafiltration of equine digital lamellar tissue.

There are no experimentally validated pharmacological means of preventing laminitis; however, locally acting pharmaceutical agents with the potential to prevent laminitis have been identified. Demonstrating therapeutic drug concentrations in lamellar tissue is essential for evaluating the efficacy of these agents. The aim of this study was to develop an experimental technique for repeatedly sampling lamellar interstitial fluid.

Bilateral diffuse cystic renal dysplasia in a 9-day-old Thoroughbred filly.

A 9-day-old Thoroughbred filly was presented for diarrhea and lethargy. Diagnostic test results were compatible with severe renal dysfunction. Diffuse cystic lesions of both kidneys were identified on ultrasonographic examination.

Prevalence of Clostridium difficile in horses.

Fecal samples were collected to establish the apparent prevalence of Clostridium difficile shedding in Standardbred and Thoroughbred racehorses housed at 4 racetracks and 2 breeding facilities, and in horses admitted to a referral large animal clinic. Forty-one (7.59%) of 540 racetrack horses, seven (5.

Hypoxia and a hypoxia mimetic up-regulate matrix metalloproteinase 2 and 9 in equine laminar keratinocytes.

The aim of this study was to determine if hypoxia and the hypoxia mimetic cobalt chloride regulate the activity of matrix metalloproteinase (MMP)-2 and -9 in cultures of equine hoof keratinocytes. These effects were assessed in primary cultures of laminar keratinocytes using gelatin zymography. Incubation of keratinocytes with cobalt chloride significantly increased the levels of active MMP-2 compared to untreated controls.