Rational quinidine dosage regimen for atrial fibrillation in Thoroughbred racehorses based on population pharmacokinetics.

Introduction: Quinidine (QND) sulfate is an effective treatment for atrial fibrillation (AF) in horses, and several dosage regimens have been proposed to address its wide variability in response and potential adverse effects. The purpose of this study was to analyze the variability in plasma quinidine concentrations using population pharmacokinetics to determine an effective and safe dosage regimen for Thoroughbred horses.

Methods: Six healthy Thoroughbred horses were treated with 20 mg/kg quinidine sulfate dihydrate (16.

Prevalence of equine proliferative enteropathy in Hidaka district, Hokkaido, over five seasons.

Equine proliferative enteropathy (EPE) is an equine infectious disease that can lead to severe weight loss and hyperplasia of the intestinal mucosa due to infection with Lawsonia intracellularis. In this study, we investigated the prevalence of EPE in a major Thoroughbred breeding area: Hidaka district, Hokkaido, Japan. Of the 252 symptomatic horses that we tested, 192 EPE cases (76.

Immunohistochemical Characteristics of Spindle Cell Ameloblastic Carcinoma in a Horse.

A 2-year-old male Thoroughbred horse presented with a mass in the maxilla. The focally ulcerated mass, approximately 8 cm in diameter, covered the upper left intermediate and corner incisor teeth (nos. 602 and 603 according to the modified Triadan system) and radiographic examination revealed displacement and lysis of the incisors.

Outbreak of methicillin-resistant sequence type 1, type t1784, in an equine hospital in Japan.

Methicillin-resistant (MRSA) has often been isolated from livestock and companion animals, including horses. Seven cases of MRSA infection in Thoroughbred racehorses were observed in an equine hospital in Japan in 2020. In this study, MRSA isolates from these seven horses and nine veterinarians in the equine hospital were studied to examine their genetic relatedness and evaluate the possibility of MRSA transmission.

Simultaneous Daily Fecal Microbiota Transplantation Fails to Prevent Metronidazole-Induced Dysbiosis of Equine Gut Microbiota.

Antimicrobial administration can lead to imbalances of gastrointestinal microbiota, called dysbiosis. Dysbiosis sometimes results in diarrhea and enteritis in horses. Fecal microbiota transplantation (FMT) is used to treat affected horses, but whether it is effective as a prophylactic approach for dysbiosis in horses receiving antimicrobials remains unknown.

High prevalence of Mycoplasma equirhinis in Thoroughbred horses with respiratory symptoms in autumn 2018.

Mycoplasma species are often isolated from horses with respiratory symptoms; however, the pathogenicity of Mycoplasma is still unclear. In autumn of 2018, we encountered an increase in cases with respiratory symptoms, mainly coughing, in a group of Thoroughbred racehorses in Japan. We examined tracheal wash samples obtained from 40 of those cases.

Construction and Application of an In-House Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) Database Specific to Bacteria From Horses.

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is used for identification of bacterial species isolated from horses. However, because of insufficiencies in the reference database, some bacterial species isolated from horses are difficult to identify with MALDI-TOF MS, and enriching the databases is expected to enhance the accuracy of MALDI-TOF MS identification. Here we created an in-house database including 271 bacterial isolates from horses.

Antifungal susceptibility of dermatophytes from racehorses in Japan.

Background: Luliconazole (LCZ) is an imidazole antifungal medication that exhibits excellent activity against dermatophytes. As a topical cream and lotion (approved for human use), LCZ has demonstrated a broad spectrum of activity against human dermatophytoses.

Objectives: This is the first study to investigate the in vitro susceptibility of clinical isolates from horse dermatophytoses to LCZ.

Establishment and assessment of an amplicon sequencing method targeting the 16S-ITS-23S rRNA operon for analysis of the equine gut microbiome.

Microbial communities are commonly studied by using amplicon sequencing of part of the 16S rRNA gene. Sequencing of the full-length 16S rRNA gene can provide higher taxonomic resolution and accuracy. To obtain even higher taxonomic resolution, with as few false-positives as possible, we assessed a method using long amplicon sequencing targeting the rRNA operon combined with a CCMetagen pipeline.

The Clonal Population of Trichophyton equinum from Dermatophytoses of Japanese Racehorses.

Trichophyton equinum is a zoophilic dermatophyte that is frequently isolated from horse dermatophytosis and rare infections in humans. In the present study, molecular and physiological testing were performed on T. equinum isolates from dermatophytoses of Japanese racehorses to assess genotype and phenotype patterns of these strains.

First isolation of from a horse with dermatophytosis in Japan.

is a zoophilic dermatophyte that has been rarely isolated from horses and humans in Africa and Europe. This is the first reported isolation of from a horse with dermatophytosis in Japan. The isolate from a skin lesion formed a cream-colored and waxy colony that was slightly elevated in the center.

Genotyping of Equine Lawsonia intracellularis Sampled in Japan by Using Multilocus Variable-Number Tandem Repeat Analysis.

The incidence of equine proliferative enteropathy, caused by Lawsonia intracellularis, is increasing around the world. To investigate the relationships of variable-number tandem repeat (VNTR) patterns with host species and clinical status in horses, multilocus VNTR analysis (MLVA) was applied to 98 L. intracellularis samples collected from horses, seven from pigs, seven from wildlife, one vaccine strain, and 17 public strains.

Ten cases of Mycobacterium avium subsp. hominissuis infections linked to equine abortions in Japan, 2018-2019.

Bacterial placentitis in horses commonly results in abortion, premature birth or compromised neonatal foal health. Although mycobacterial infections are generally uncommon in horses, 10 equine abortion cases caused by Mycobacterium avium subsp. hominissuis (MAH) infections occurred between 2018 and 2019 in Japan.

Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) for Identification of Bacterial Isolates From Horses.

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is used for bacterial identification by analyzing the spectra of isolates and comparing them against a database of reference spectra; it is known for its rapidity and accuracy. Although MALDI-TOF MS is used for identification of bacterial isolates from animals, not all animal pathogens are identified correctly. In this study, we used a commercial MALDI-TOF MS identification system to examine 3724 bacterial isolates from horses and their environments.

Molecular phylogenetic and matrix-assisted laser desorption ionization time-of-flight mass spectrometry identification of isolates from horses identified as by biochemical identification.

Enterobacter cloacae is an opportunistic pathogen of horses. Thirty isolates obtained from horses and their environments and identified as Enterobacter cloacae by biochemical methods were reidentified by taxonomic identification based on multilocus sequence analysis (MLSA) and by a commercial identification system based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). MLSA identified the 30 equine isolates as E.

Complete Genome Sequence of Mycoplasma felis Strain Myco-2, Isolated from an Equine Tracheal Wash Sample in Japan.

causes conjunctivitis in cats and respiratory diseases in horses. We report here the complete genome assembly of equine strain Myco-2, which was isolated from an ill horse in Japan.

Complete Genome Sequence of Mycobacterium avium subsp. Strain JP-H-1, Isolated from an Equine Abortion Case in Japan.

Here, we describe the complete genome assembly of subsp. strain JP-H-1, collected from an equine abortion case in Japan. JP-H-1 has a 5,491,452-bp circular chromosome and 3 plasmids.

Actinobacillus species isolated from Japanese Thoroughbred racehorses in the last two decades.

Actinobacillus species are known to be pathogenic to horses. To clarify etiological agents of actinobacillosis in Japanese adult horses, 27 isolates from Japanese Thoroughbred racehorses putatively identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry as Actinobacillus were further identified by PCR of the A. equuli toxin gene, by CAMP test, and by 16S rRNA sequencing analysis.

Histopathological characteristics of an ossifying fibroma formed in the maxilla of a racehorse.

A 1-year-old male thoroughbred racehorse experienced swelling of the left upper lip. The swelling was attributable to enlargement around the incisive bone of the interdental space posterior to the third incisor in the left maxilla. Even after two operations to reduce the bulk of the mass, it continued to increase in size.