Intra-articular injection of an extended-release flavopiridol formulation represents a potential alternative to other intra-articular medications for treating equine joint disease.

Objective: To establish the pharmacokinetics of the cyclin-dependent kinase-9 inhibitor flavopiridol in equine middle carpal joints, using an extended-release poly lactic-co-glycolic acid (PLGA) microparticle formulation.

Animals: 4 healthy horses without evidence of forelimb lameness.

Methods: A 6-week longitudinal pharmacokinetic study was conducted in 2 phases (6 weeks each) in 4 healthy horses.

Effect of clodronate on gene expression in the peripheral blood of horses.

There are two FDA-approved bisphosphonate products, clodronate (Osphos®) and tiludronate (Tildren®), for use in horses. It is hypothesized that bisphosphonates can produce analgesic effects and prevent proper healing of microcracks in bone. Therefore, bisphosphonate use is banned in racehorses.

18F-sodium fluoride positron emission tomography provides pertinent additional information to computed tomography for assessment and management of tarsal pain in horses.

Objective: To assess the value of 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) for imaging the tarsus and proximal metatarsus and compare it with CT and lameness evaluation.

Animals: 25 horses with lameness localized to the tarsal and proximal metatarsal regions that underwent 18F-NaF PET/CT between 2016 and 2021.

Methods: 18F-NaF PET and CT images were retrospectively independently evaluated by 3 observers.

Septic inflammation of the bicipital bursa: clinical, imaging, and surgical findings in nine horses.

Objective: To describe the etiologies, clinicopathologic findings, diagnostic modalities employed, treatments, and outcome associated with cases of septic bicipital bursitis.

Animals: 9 horses.

Clinical Presentation And Procedures: Medical records of horses diagnosed with septic bicipital bursitis between 2000 and 2021 were reviewed.

Identification of putative orthologs of clinically relevant antimicrobial peptides in the equine ocular surface and amniotic membrane.

Objectives: This study aimed to define the antimicrobial peptide (AMP) expression pattern of the equine ocular surface and amniotic membrane using a targeted qPCR approach and 3'Tag-sequencing. It will serve as a reference for future studies of ocular surface innate immunity and amniotic membrane therapies.

Procedures: A targeted qPCR approach was used to investigate the presence of orthologs for three of the most highly expressed beta-defensins (DEFB1, DEFB4B, and DEFB103A) of the human ocular surface and amniotic membrane in equine corneal epithelium, conjunctiva, and amniotic membrane.

Postmortem diagnoses of spinal ataxia in 316 horses in California.

Objective: To determine period prevalences of postmortem diagnoses for spinal cord or vertebral column lesions as underlying causes of ataxia (spinal ataxia) in horses.

Animals: 2,861 client-owned horses (316 with ataxia [ataxic group] and 2,545 without ataxia [control group]).

Procedures: The medical records database of the University of California-Davis Veterinary Medical Teaching Hospital was searched to identify horses necropsied between January 1, 2005, and December 31, 2017.

Assessment and Revision of the Veterinary Internship and Residency Matching Program Standardized Letter of Reference.

The Veterinary Internship and Residency Matching Program (VIRMP) recently revised its electronic standardized letter of reference (SLOR) to improve the quality and usefulness of the data obtained from it and to enhance the relevance of non-cognitive and cognitive candidate attributes assessed. We used a stepwise process including a broad survey of SLOR readers and writers, analysis of past SLORs, and a multi-wave iterative revision that included key stakeholders, such as residency and internship program directors from academia and private practice. Data from the SLOR survey and analysis of past SLOR responses identified opportunities to improve applicant differentiation, mitigate positive bias, and encourage response consistency.

Fibro-Osseous Lesions Of The Craniofacial Complex In Horses: 30 Cases (2001-2019).

Objective: To describe the presentation, diagnosis, treatment, and outcome for horses with fibro-osseous lesions of the craniofacial complex.

Study Design: Retrospective multicenter case series.

Animals: Thirty horses evaluated for fibro-osseous lesions of the skull from January 1, 2001 through December 31, 2019 in four centers.

Incidence of incisional complications after exploratory celiotomy in equids affected with enterolithiasis.

This study reports the prevalence of and risk factors for incisional complications in equids after ventral midline celiotomy for enterolithiasis. This study covered the years 2008 to 2015 and included 72 equids. Enteroliths were removed from the ascending or descending colon through 1 or more enterotomies.

Chondrosesamoidean ligament enthesopathy: Prevalence and findings in a population of lame horses imaged with positron emission tomography.

Background: Increased F-Sodium Fluoride ( F-NaF) uptake at the chondrosesamoidean ligament (ChSL) attachment on the distal phalanx was identified in an exploratory positron emission tomography (PET) study. The prevalence and significance of this lesion has not been previously investigated.

Objectives: The goal of this study was to assess the prevalence of this lesion, its association with other imaging findings and with clinical signs.

3 Dimensional photonic scans for measuring body volume and muscle mass in the standing horse.

Reasons For Performing Study: Although muscle mass strongly influences performance, there is currently no effective means to measure the 3-dimensional muscle mass of horses. We evaluated a 3-dimensional (3D) scanning methodology for its ability to quantify torso and hindquarter volumes as a proxy for regional muscle mass in horses.

Objectives: Determine the repeatability of 3D scanning volume (V) measurements and their correlation to body weight, estimated body volume and muscle/fat ultrasound (US) depth.

Impact of alpha-tocopherol deficiency and supplementation on sacrocaudalis and gluteal muscle fiber histopathology and morphology in horses.

Background: A subset of horses deficient in alpha-tocopherol (α-TP) develop muscle atrophy and vitamin E-responsive myopathy (VEM) characterized by mitochondrial alterations in the sacrocaudalis dorsalis medialis muscle (SC).

Objectives: To quantify muscle histopathologic abnormalities in subclinical α-TP deficient horses before and after α-TP supplementation and compare with retrospective (r)VEM cases.

Animals: Prospective study; 16 healthy α-TP-deficient Quarter Horses.

Incomplete fracture of the talus secondary to maladaptive stress remodeling in a horse.

Case Description: A 6-year-old Quarter Horse gelding used for barrel racing was evaluated for acute onset of non-weight-bearing lameness of the left hind limb following strenuous exercise.

Clinical Findings: Nuclear scintigraphic imaging revealed focal increased radiopharmaceutical uptake centrally within the left talus. Subsequent standard radiographic and ultrasonographic examinations of the tarsus failed to identify the cause of the increased radiopharmaceutical uptake; however, the lameness was definitively localized to the tarsocrural joint by intra-articular anesthesia.

Pathological Safety Assessment in Preclinical Neurothrombectomy Studies.

The design, production, and preclinical testing of neurothrombectomy devices is in a burgeoning phase as the demand escalates for safe and reliable treatment options following neurovascular stroke. Currently, there is a paucity of published data describing the development of iatrogenic vascular lesions occurring secondary to neurothrombectomy procedures. In an effort to test new devices, demonstrate device safety, satisfy regulatory requirements, and develop an understanding of the potential for associated vascular pathology, investigators are establishing appropriate methodology in suitable animal models.

Outcome following computed tomographic imaging and subsequent surgical removal of keratomas in equids: 32 cases (2005-2016).

OBJECTIVE To describe the use of CT in the diagnosis of and presurgical planning for equids with keratomas treated by hoof wall resection and determine postoperative complications and outcome. DESIGN Retrospective case series. ANIMALS 29 horses and 3 mules with keratomas treated by partial or complete hoof wall resection following CT imaging of the distal portion of the affected extremity from 2005 through 2016.

Use of a locking compression plate for equine proximal interphalangeal joint arthrodesis: 29 cases (2008-2014).

OBJECTIVE To describe clinical use of a locking compression plate (LCP) for proximal interphalangeal joint (PIPJ) arthrodesis in horses and compare outcomes for horses that underwent the procedure as treatment for fracture of the middle phalanx (P2) versus other causes. DESIGN Retrospective case series. ANIMALS 29 client-owned horses.

A novel ultrasonographic assisted technique for desmotomy of the palmar/plantar annular ligament in horses.

Objectives: To describe an ultrasound assisted technique for desmotomy of the palmar/plantar annular ligament (PAL), determine its efficacy and intraoperative complications.

Study Design: Cadaveric and in vivo study.

Animals: Cadaveric limbs (n = 12), adult horses (n = 4), and clinical cases (n = 2).

POSITRON EMISSION TOMOGRAPHY OF THE EQUINE DISTAL LIMB: EXPLORATORY STUDY.

Positron emission tomography (PET) is a highly sensitive, noninvasive imaging technique for quantifying biological functions of tissues. However, at the time of this study, PET imaging applications had not been reported in the horse. The aim of this exploratory study was to determine whether a portable high-resolution PET scanner could be used to image the equine distal limb.

Use of a laparoscopic specimen retrieval pouch to facilitate removal of intact or fragmented cystic calculi from standing sedated horses: 8 cases (2012-2015).

OBJECTIVE To evaluate the use of a laparoscopic specimen retrieval pouch for removal of intact or fragmented cystic calculi from standing horses. DESIGN Retrospective case series. ANIMALS 8 horses (5 geldings and 3 mares) with cystic calculi.

FRACTURE OF THE CENTRAL TARSAL BONE IN NONRACEHORSES: FOUR CASES.

Fractures of the central tarsal bone are a rarely recognized cause of acute severe hind limb lameness in nonracehorses. Diagnosis of these fractures can be challenging and little is known about their configuration or outcome. The objectives of this retrospective case series study were to describe the clinical features, imaging findings, and outcomes of fractures of the central tarsal bone in a sample of nonracehorses.

Use of zoledronate for treatment of a bone fragility disorder in horses.

Objective: To assess clinical outcomes and scintigraphic findings in horses with a bone fragility disorder (BFD) treated with zoledronate (a nitrogen-containing bisphosphonate).

Design: Prospective uncontrolled clinical trial.

Animals: 10 horses with evidence of a BFD.