Yearling laryngeal function grades II.2 and below are not associated with reduced performance.

Background: The relationship between Thoroughbred yearling laryngeal function (YLF) grade and race performance is unclear.

Objectives: To determine the effect of YLF on future race performance.

Study Design: Retrospective cohort study.

A first step towards objective grading of equine laryngeal function.

Due to concerns about disagreement between veterinarians when grading resting laryngeal function (LF), a diagnostic decision tree (DDT) has been developed by codifying the Havemeyer grading system and objectively defining certain terms to remove ambiguity. Videoendoscopic examinations of the equine larynx that had previously been assigned a unanimous LF grade by 3 experienced observers were used to develop the DDT and determine the cut-off values. The DDT is a flow chart consisting of a series of dichotomous (yes/no) decisions, to dictate the order of decision making and direct the observer down a pathway towards the most appropriate LF grade.

Heritability of sudden cardiac death in Thoroughbred racehorses.

Background: Sudden cardiac death (SCD) is an important cause of exercise-associated fatalities in Thoroughbred racehorses. Equine deaths share similarities with fatalities in human athletes that result from inherited cardiac disease. Whilst genetic causes have been postulated in horses, these have not been confirmed and heritability of SCD has not previously been estimated in Thoroughbred racehorses.

Yearling laryngeal function in Thoroughbreds that underwent a laryngoplasty differs from controls.

Background: Yearling laryngeal function (YLF) is frequently assessed at the time of sale and the outcomes of these assessments can have significant economic implications. The YLF of horses that subsequently underwent a prosthetic laryngoplasty (PL) is unknown.

Objectives: We hypothesised horses with YLF ≥grade II.

Standing left recurrent laryngeal neurectomy for prospective evaluation of laryngeal hemiplegia evaluated by a high-speed treadmill test.

Objective: To describe left recurrent laryngeal neurectomy (LRLn) performed under standing sedation and evaluate the effect of LRLn on upper respiratory tract function using a high-speed treadmill test (HST). We hypothesized that (1) unilateral LRLn could be performed in standing horses, resulting in ipsilateral arytenoid cartilage collapse (ACC); and (2) HST after LRLn would be associated with alterations in upper respiratory function consistent with dynamic ACC.

Animals: 6 Thoroughbred horses.

Associations between postrace atrial fibrillation and measures of performance, racing history and airway disease in horses.

Background: Atrial fibrillation (AF) is the most common performance limiting arrhythmia in racehorses. High dose exercise and airway disease promote AF in humans. Few studies have investigated epidemiological factors associated with AF in horses.

Identification and kinetics of microsomal and recombinant equine liver cytochrome P450 enzymes responsible for in vitro metabolism of omeprazole.

In humans, omeprazole is metabolised by cytochrome P450 (CYP450) CYP2C19 and CYP3A4 with differences in CYP2C19 genotypes leading to variable response to therapy. Despite a wide use of omeprazole in horses with evidence of variable therapeutic efficiency, information regarding enzymatic metabolism is not currently available. This study aims to describe the in vitro kinetics of omeprazole metabolism and determine which enzyme(s) are responsible for omeprazole metabolism in horses.

Horse Grimace Scale Does Not Detect Pain in Horses with Equine Gastric Ulcer Syndrome.

Equine gastric ulcer syndrome (EGUS) is a highly prevalent and presumptively painful condition, although the amount of pain horses might experience is currently unknown. The aims of this study were to determine if the Horse Grimace Scale (HGS) could identify pain behaviours in horses with and without EGUS and if severity would be positively associated with the HGS score. Horse grimace scale scores were assessed blindly using facial photographs by seven observers and involved evaluation of 6 facial action units as 0 (not present), 1 (moderately present) and 2 (obviously present).

Contribution of the Oral and Gastrointestinal Microbiomes to Bloodstream Infections in Leukemia Patients.

Bloodstream infections (BSIs) pose a significant mortality risk for acute myeloid leukemia (AML) patients. It has been previously reported that intestinal domination (>30% relative abundance [RA] attributed to a single taxon) with the infecting taxa often precedes BSI in stem cell transplant patients. Using 16S rRNA amplicon sequencing, we analyzed oral and stool samples from 63 AML patients with BSIs to determine the correlation between the infectious agent and microbiome composition.

Assessment of P Wave Indices in Healthy Standardbred Horses.

P wave indices are used as non-invasive electrocardiographic markers of atrial remodelling in humans. Few studies have investigated their use in animals. The aim of this study was to measure P wave duration and P wave dispersion (Pd) in healthy standardbred horses and investigate variables that might influence these measurements.

Heart rate variability during high-speed treadmill exercise and recovery in Thoroughbred racehorses presented for poor performance.

Background: Heart rate variability (HRV) analysis measures the inter-beat interval variation of successive cardiac cycles. Measurement of these indices has been used to assess cardiac autonomic modulation and for arrhythmia identification in exercising horses.

Objectives: To report HRV indices during submaximal exercise, strenuous exercise and recovery, and explore relationships with clinical conditions (arrhythmias, lameness, equine gastric ulcer syndrome [EGUS], lower airway inflammation and upper respiratory tract obstructions [URTOs]) in Thoroughbred racehorses.

The Neuroimmune Interface and Chronic Pain Through the Lens of Production Animals.

Communication between the central nervous system (CNS) and the immune system has gained much attention for its fundamental role in the development of chronic and pathological pain in humans and rodent models. Following peripheral nerve injury, neuroimmune signaling within the CNS plays an important role in the pathophysiological changes in pain sensitivity that lead to chronic pain. In production animals, routine husbandry procedures such as tail docking and castration, often involve some degree of inflammation and peripheral nerve injury and consequently may lead to chronic pain.

Risk Factors for Exercise-Associated Sudden Cardiac Death in Thoroughbred Racehorses.

Cardiac arrhythmias resulting in sudden cardiac death (SCD) are an important cause of racehorse fatalities. The objective of this study was to determine risk factors for SCD in Thoroughbreds by evaluating a sample with a policy of mandatory post-mortem following racing or training fatalities. Risk factors were compared between case horses with SCD (n = 57) and control horses with other fatal injury (OFI, n = 188) by univariable and multivariable logistic regression.

Oral and Stool Microbiome Coalescence and Its Association With Antibiotic Exposure in Acute Leukemia Patients.

Failure to maintain segregation of oral and gut microbial communities has been linked to several diseases. We sought to characterize oral-fecal microbiome community coalescence, ectopic extension of oral bacteria, clinical variables contributing to this phenomenon, and associated infectious consequences by analyzing the 16S rRNA V4 sequences of longitudinal fecal (n=551) and oral (n=737) samples from 97 patients with acute myeloid leukemia (AML) receiving induction chemotherapy (IC). Clustering observed in permutation based multivariate analysis of variance (PERMANOVA) of Bray-Curtis dissimilarity and PCoA plot of UniFrac distances between intra-patient longitudinal oral-stool sample pairs suggested potential oral-stool microbial community coalescence.

Validation of an equine fitness tracker: ECG quality and arrhythmia detection.

Background: Cardiac arrhythmias in exercising horses are the focus of much interest, both in terms of what is considered normal and potential associations with poor performance and sudden cardiac death. One barrier to performing large-scale studies is the lack of an easily applicable device, to allow recording of large numbers of high-quality exercising electrocardiograms (ECGs). The Equimetre is a new wearable device which records a single lead ECG, amongst other parameters.

Continuous Monitoring of the Thermoregulatory Response in Endurance Horses and Trotter Horses During Field Exercise: Baselining for Future Hot Weather Studies.

Establishing proper policies regarding the recognition and prevention of equine heat stress becomes increasingly important, especially in the face of global warming. To assist this, a detailed view of the variability of equine thermoregulation during field exercise and recovery is essential. 13 endurance horses and 12 trotter horses were equipped with continuous monitoring devices [gastrointestinal (GI) pill, heartrate (HR) monitor, and global positioning system] and monitored under cool weather conditions during four endurance rides over a total of 80 km (40 km loops) and intense trotter track-based exercise over 1,540 m.

The Reported Use of Tongue-Ties and Nosebands in Thoroughbred and Standardbred Horse Racing-A Pilot Study.

This article reports on the results of a survey of racehorse trainers ( = 112) outlining the reasons for tongue-tie (TT) and noseband (NB) use by Thoroughbred trainers (TBTs) ( = 72) and Standardbred trainers (SBTs) ( = 40). The study also investigated the reported effectiveness of TTs and possible complications arising from their use. Tongue-tie use was reported by 62.

Incidence, recurrence, and outcome of postrace atrial fibrillation in Thoroughbred horses.

Background: Atrial fibrillation (AF) impacts performance and horse and jockey safety. Understanding the outcomes of AF identified postrace will better inform regulatory policy.

Hypothesis/objectives: To investigate the outcomes after episodes of AF identified postrace and determine whether affected horses are at increased risk of additional episodes compared to the general racing population.

Exercise-associated rhythm disturbances in poorly performing Thoroughbreds: risk factors and association with racing performance.

Background: Exercise-associated cardiac rhythm disturbances are common, but there is a lack of evidence-based criteria on which to distinguish clinically relevant rhythm disturbances from those that are not.

Objectives: To describe and characterise rhythm disturbances during clinical exercise testing; to explore potential risk factors for these rhythm disturbances and to determine whether they influenced future racing.

Study Design: Retrospective cohort using a convenience sample.

The Reported Use of Nosebands in Racing and Equestrian Pursuits.

This article reports on the results of a survey designed to explore the types of nosebands that owners, riders and trainers use in training and competition, their reasons for using nosebands, the design preferences in different disciplines and approaches to noseband tightness and monitoring, as well as the incidence of negative impacts related to noseband usage. Respondents ( = 3040) were asked to specify the type of noseband they were currently using and to rate how effective they were in achieving these stated reasons. Respondents who used nosebands ( = 2332) most commonly used Plain Cavesson (46.

Hair cortisol concentration is inversely related to the severity of equine squamous gastric disease.

Equine squamous gastric disease (ESGD) is common in horses and many factors, including stress, may play a role in lesion development. Hair cortisol concentration (HCC) provides a measure of medium to long-term stress and therefore, the relationship between HCC and ESGD was examined in this study. Hair samples were collected from 25 horses and gastroscopy was performed to determine the presence and severity of ESGD.

Evaluation of a prototype dynamic laryngoplasty system in vitro with an equine vacuum airflow system.

Objective: To evaluate a prototype dynamic laryngoplasty system (DLPS) in a static airflow model.

Study Design: Experimental.

Sample Population: Ten equine larynges.

In vitro evaluation of the effect of a prototype dynamic laryngoplasty system on arytenoid abduction.

Objective: To determine the effect of a prototype dynamic laryngoplasty system (DLPS) on arytenoid abduction.

Study Design: In vitro experimental.

Study Population: Ten equine larynges.