Topic:Antibiotics
Antibiotics are medications used to treat bacterial infections in horses. They work by either killing bacteria or inhibiting their growth, aiding the horse's immune system in overcoming the infection. Commonly used antibiotics in equine medicine include penicillin, trimethoprim-sulfamethoxazole, and gentamicin. The selection of an antibiotic depends on factors such as the type of bacteria, the site of infection, and the horse's health status. Responsible use of antibiotics is essential to minimize the risk of resistance. This page compiles peer-reviewed research studies and scholarly articles that explore the efficacy, administration, and impact of antibiotics on equine health.
Evolution of in vitro antimicrobial resistance at an equine hospital over 4 decades. This study aimed to document antimicrobial resistance patterns of bacteria frequently isolated at a referral equine hospital between 2020 and 2022 and to compare these results to those of studies carried out in previous decades at the same reference center. Unassigned: Using the Kirby-Bauer method, 340 tests were completed on bacterial isolates and compared to 233, 255, and 396 tests carried out in 1986 to 1988, 1996 to 1998, and 2007 to 2013, respectively. Data were analyzed with tests for trends, followed by pairwise Fisher tests and Bonferroni corrections. Unassigned: Increasing resistanc...
Clinical safety of intrauterine infusion of a uterine sanitizer in mares. Limited response to conventional therapies and rising antibiotic resistance emphasize the need for alternative treatments for infectious endometritis. A recent in vitro study showed promising antimicrobial activity of a commercial uterine cleaning sanitizer (UCS) against endometritis pathogens. However, its safety and efficacy in mares remain untested. Objective: This study aimed to assess the clinical safety of intrauterine infusion of UCS in reproductively sound mares. Methods: Exp. 1. Six healthy mares with endometrial biopsies classified as I or IIA had two intrauterine infusions of UCS pe...
Pigments with antimicrobial and cytotoxic activities from the coprophilous fungus Fusarium solani isolated from horse dung. Four previously undescribed phenazine-derived pigments (1-4), along with seventeen known compounds, were isolated from a strain cultured on solid rice medium. Structural elucidation of the new compounds was achieved through extensive spectroscopic analysis, while known compounds were identified by comparison with literature data. The antimicrobial and cytotoxic activities of the isolated compounds were assessed. Compounds 2, 5, and 11 exhibited weak antifungal activity against at 200 μM, while compounds 5, 6, 11, 12, 15, and 20 demonstrated moderate antibacterial effects against at the sam...
Possible association of short-term complications and antimicrobial use in standing equine cheek tooth extractions 2018-2022. Despite growing concerns about antimicrobial resistance, prophylactic antimicrobials continue to be routinely administered in many procedures, including dental extractions. Further evidence-based research is needed on whether their use influences post-operative complication rates. Objective: To identify risk factors for short-term complications, associations between complications and antimicrobial use as well as factors leading to antimicrobial use in equine (standing) cheek tooth extractions. Methods: Retrospective analysis of clinical records. Methods: Data were extracted from records of hor...
Antimicrobial Resistance Patterns of Staphylococcus aureus Cultured from the Healthy Horses’ Nostrils Sampled in Distant Regions of Brazil. () is a major cause of opportunistic infections in humans and animals, leading to severe systemic diseases. The rise of MDR strains associated with animal carriage poses significant health challenges, underscoring the need to investigate animal-derived . Objective: This study examined the genotypic relatedness and phenotypic profiles of antimicrobial resistance in . , previously sampled from nostril swabs of healthy horses from two geographically distant Brazilian states (Northeast and South), separated by over 3700 km. The study also sought to confirm the presence of methicillin-resistant (M...
Pharmacokinetics/pharmacodynamics analysis of trimethoprim and sulfamethoxazole for methicillin-resistant Staphylococcus aureus infection after intravenous and per os administration in Thoroughbred horses. A pharmacokinetics/pharmacodynamics (PK/PD) approach was used to determine the dosage regimens of trimethoprim/sulfamethoxazole for methicillin-resistant Staphylococcus aureus (MRSA) infections after intravenous (IV) and per os (PO) administration in horses. Methods: Trimethoprim/sulfamethoxazole plasma concentrations were measured in six horses after a single IV administration of 15 mg/kg (2.5 mg/kg trimethoprim and 12.5 mg/kg sulfamethoxazole) and PO administration of 30 mg/kg (5.0 mg/kg trimethoprim and 25.0 mg/kg sulfamethoxazole). The data were modeled using a nonlinear mixed-effects mode...
Emergence of ciprofloxacin- and tigecycline-resistant extended-spectrum β-lactamase (ESBL)-producing Salmonella enterica serovar Kentucky ST198 from horse, China. Salmonella enterica serovar Kentucky ST198 has been increasingly reported in diverse sources worldwide, emerging as a globally epidemic clone. In this study, we aim to characterise the first isolated S. Kentucky ST198 strain from a horse in China. Methods: Twelve faecal samples were collected from horses at a farm in Shihezi, Xinjiang Province, China, and investigated for the presence of Salmonella. The minimum inhibitory concentrations of 15 antimicrobial agents were determined using the broth microdilution method. The whole genome of Sal140 was sequenced using the Illumina Hiseq platform and...
Complications associated with subpalpebral lavage systems in upper and lower equine eyelids: A prospective, randomised study in 73 cases (2015-2024). Evidence for optimal location of subpalpebral lavage (SPL) systems is lacking. Objective: To compare the rate and types of complications with SPL systems located in central upper- compared with medial lower-eyelid in hospitalised patients. Methods: Prospective, randomised treatment trial. Methods: Horses admitted for ophthalmic treatment using an SPL system from February 2015 to January 2024 were included if ocular pathology did not necessitate SPL system placement in a specific location. Coin toss was used to determine location. SPL systems were monitored at least daily, and complications wer...
Antimicrobial resistance in bacteria isolated from diseased horses in Poland, 2010-2022. The rise of antibiotic resistance is a global health crisis affecting human and veterinary medicine, highlighted within the One Health framework. Horses, classified as both meat and companion animals, play a crucial role in facilitating resistant bacteria spread to humans. Despite increased awareness and reduced antibiotic use in livestock, data on equine antibiotic use and resistance remain limited. This retrospective study examines antimicrobial resistance in 978 bacterial isolates from horses in Poland over 12 years (2010-2022), utilizing data from the Microbiological Diagnostic Laboratory ...
Is Rifampin (Rifampicin) Essential for the Treatment of Rhodococcus equi Infections in Foals? A Critical Review of the Role of Rifampin. Rifampin is an enigma among antimicrobials. Blood and tissue compartment concentrations are a "moving target" along the treatment course due to the complex pharmacodynamic interactions within the body. Rifampin concomitant therapies are for the prevention and treatment of Rhodococcus equi infection in foals, for nearly 40 years. The necessity of rifampin concomitant therapies is based on beliefs that both antimicrobials (e.g., rifampin plus macrolide) penetrate into pulmonary abscesses and intracellular compartments above R. equi minimum inhibitory concentrations (MICs), as well as better ef...
Perioperative factors and outcomes associated with antimicrobial therapy duration in horses undergoing exploratory celiotomy. The objective was to compare perioperative factors that may influence clinician decisions regarding antimicrobial therapy duration and outcomes in horses undergoing exploratory celiotomy. Unassigned: Horses > 1 mo of age undergoing exploratory celiotomy for colic that survived without repeat celiotomy for ≥ 5 d. Unassigned: Retrospective cohort study. Cases were grouped by duration of antimicrobial therapy: G1, ≤ 24 h; G2, 1 to 3 d; G3, > 3 d. Admission, surgical, and postoperative data from the medical records and long-term outcome assessed telephone follow-up were compared among g...
[Off-label use of antibiotics in equine medicine – an online survey in Germany]. Since 28.01.2022, veterinary medicinal products must be used in accordance with the conditions of authorization (Regulation (EU) 2019/6, Article 106). This entails further restrictions on therapeutic freedom, e. g., with regard to dose deviations. To date, there is no data available in equine medicine on the scope of off-label use as any use deviating from the expert information for antibiotics, on the basis of which the feasibility of implementing the new regulations in Germany can be assessed.To collect data on the off-label use of antibiotics, a Germany-wide anonymous online survey was th...
Use of a point prevalence survey to measure antimicrobial use and antimicrobial resistance in equine veterinary hospitals. Antimicrobial resistance (AMR) is increasingly recognised in equine medicine. Antimicrobial use (AMU) is a key driver of AMR. Objective: To pilot a point prevalence survey (PPS), based on the Global-PPS used in human hospitals, to obtain data on antibiotic prescribing and AMR in equine hospitals and to identify targets for improvement in AMU. Methods: Point prevalence survey. Methods: Eight equine hospitals located in Australia, Belgium, South Africa, the United Kingdom and the United States were recruited. Data on AMU were collected from all in-patients on antibiotic treatment at 08h00 on fou...
Knowledge levels regarding antibiotics and their use among horse owners in the State of Rio Grande do Norte, Brazil. This study aimed to evaluate the use of antimicrobials in horses, focusing on administration practices, adherence to veterinary prescriptions, and the impact on the development of antimicrobial resistance. The research was based on a questionnaire completed by 220 horse owners in the State of Rio Grande do Norte, Brazil. The data collected covered aspects including antibiotic use, prescription sources, the performance of culture and susceptibility tests, and the disposal of veterinary drug waste. The results indicated that 98.63% of horse owners administered antibiotics mainly to treat respira...
Headshaking associated with a unique presentation of guttural pouches infection and otitis media in a Quarter Horse stallion: diagnosis, medical treatment and outcome. A 3-year-old Quarter Horse stallion was referred for headshaking (HS) syndrome of one month duration. The horse underwent complete HS workup. Physical examination revealed up-and-down head movements associated with nose snorting during lunging and riding, in the absence of other abnormalities at rest or in motion. Lameness, neurologic and behavioural evaluations were unremarkable. Endoscopic examination of the upper respiratory tract showed bilateral guttural pouches (GPs) inflammation. The mucosal surface was altered by the presence of areas of microbullous appearance coalescing into some bul...
Pharmacokinetics of Chloramphenicol and Chloramphenicol Glucuronide in Horses Following Administration Per Rectum or via Nasogastric Intubation. Chloramphenicol is a broad-spectrum antibiotic used in equine practice. It is known to produce adverse effects of hyporexia/anorexia after oral administration. Administration per rectum (PR) could mitigate the appetite suppression seen with oral administration and allow its use in horses unable to receive oral medications. The objectives of this study were to evaluate the relative bioavailability of chloramphenicol administered PR or via nasogastric tube (NGT) and determine relevant pharmacokinetic/pharmacodynamic parameters and metabolic ratios. Ten healthy, adult horses were administered chl...
Identification and molecular characteristics of Staphylococcus aureus isolated from horses in Lichuan, China. Staphylococcus aureus can transfer from animals to humans. Lichuan horse is an isolated breed living in a high-altitude area with limited use of antibiotics and is bred for use in tourism. To evaluate the risk of human-animal cross-transmission, the S. aureus was isolated from three horse farms in Lichuan, including healthy horses and horses with skin infections, farm workers and environment. From a collection of 111 samples, 18 S. aureus isolates were obtained. All the isolates were genome sequenced and their biological characteristics including antimicrobial susceptibility, virulence and bi...
Understanding antimicrobial use by equine owners in Wales: Using cross-sectional survey and semi-structured interviews. Antimicrobial resistance (AMR) is an increasingly serious threat to human and animal health. Antimicrobial use (AMU) in horses is gathering research interest, although there remain significant evidence gaps. Currently, there is scant qualitative research into equine owners' use of antimicrobials, specifically antibiotics, hindering the design of evidence-based stewardship interventions and policies. Objective: To understand Welsh equine owners' views and behaviours relating to antimicrobial usage. Methods: Cross sectional survey and qualitative data collection and analysis. Methods: An online ...
Equine epiglottitis: Diagnosis, treatment and outcome. Epiglottitis is an uncommon upper airway pathology manifested endoscopically by mucosal oedema, reddening and thickening of the epiglottic mucosa. Literature on epiglottitis in horses is sparse. Objective: To describe the diagnosis, treatment and outcome of Thoroughbred and Standardbred racehorses diagnosed with epiglottitis at a single centre. A secondary objective is to demonstrate the efficacy of inhaled and topical anti-inflammatories for this condition. Methods: Retrospective case series. Methods: Medical records (2009-2023) were reviewed for racehorses treated for epiglottitis. Data coll...
Presumptive Lyme disease-associated eosinophilic synovitis in a horse. A 1-year-old American Quarter horse was presented with acute onset of right hind lameness. On physical examination, there was synovial effusion of the right tarsocrural joint. Synovial fluid cytology revealed a marked eosinophilic synovitis. Serology indicated evidence of acute and chronic infection with Borrelia burgdorferi, although PCR of the synovial fluid was negative. The filly was treated with phenylbutazone and oxytetracycline, and repeated synovial cytology indicated improvement. The filly was discharged with a prescription of minocycline for 30 days. Despite initial improvement, recu...
Leptospirosis. Leptospirosis is a zoonotic bacterial infection that is prevalent across all continents and is caused by pathogenic spirochaetes of the genus Leptospira. Although infection can be asymptomatic, symptomatic disease can vary in severity from mild to severe illness, the latter characterized by icterus and/or multi-organ dysfunction and potentially death. An estimated one million cases of leptospirosis occur globally each year, resulting in ~60,000 deaths. The pathogenesis of severe leptospirosis is poorly understood but is believed to involve an interplay between genetic predisposition, pathogen ...
Minimal disruption of equine gut microbiota by intravenous cephalothin treatment. In horses, the gut microbiota plays a critical role in maintaining intestinal homeostasis and overall health, but antimicrobial administration can disrupt its balance, resulting in dysbiosis, which can cause antibiotic-associated diarrhea. This study assessed the impact of intravenous cephalothin sodium administration on the equine gut microbiota by using microbial amplicon sequencing targeting the 16S-ITS-23S rRNA operon. Fecal samples from 39 clinically normal horses, 16 antibiotic-treated horses (cephalothin, n=5; minocycline, n=5; metronidazole, n=6, each administered for 5 days), and seve...
Intra- and Post-Operative Bacteriological Surveys of Surgical Site in Horses: A Single-Centre Study. Bacterial contamination of the surgical site in horses is a major risk factor for the development of surgical site infections (SSIs), which increase morbidity, mortality, the hospitalisation period, antibiotic use, and management costs. While contamination is a prerequisite for infection, its progression to clinical infection depends on additional factors that compromise host defences. The present study, conducted at the Veterinary Teaching Hospital of the University of Perugia over an 11-month period, investigated bacterial contamination in 70 surgeries (53 clean and 17 clean-contaminated) at...
A Laboratory Protocol for Routine Therapeutic Drug Monitoring of Beta-Lactams Antimicrobials in Horses and Dogs. Background: Although antibiotic resistance is a well-known issue in veterinary medicine, studies proposing real-time therapeutic monitoring (TDM) are lacking. The objective of the present study was to develop a simple and rapid protocol for the real-time therapeutic monitoring of antibiotics in horses and dogs. Methods: A reliable TDM protocol should encompass guidelines for the definition of plasma/serum collection time points, sample management by the clinical staff, transportation to the laboratory, and the availability of robust and swift analytical technologies. Ampicillin and sulbactam w...
Survey of the antimicrobial susceptibility of Escherichia coli isolated from horses admitted to the Western College of Veterinary Medicine, Saskatoon, Saskatchewan. Antimicrobial resistance is a serious threat in human and veterinary medicine. Among the most problematic resistant organisms are the extended-spectrum β-lactamase (ESBL)-producing Enterobacterales, which are resistant to the 3rd-generation cephalosporins. The purpose of this study was to determine the frequency of colonization of horses admitted to the Western College of Veterinary Medicine with resistant Escherichia coli. Unassigned: Rectal swabs were collected from 60 horses admitted between November 2021 and March 2022. Swabs were selectively cultured for E. coli, which was identified usi...
Influence of antimicrobial prophylaxis in horses undergoing sutured castrations. To investigate the influence of surgical antimicrobial prophylaxis (SAP) on complication rates and surgical site infections (SSI) in horses undergoing sutured castration in a hospital setting. Methods: Retrospective chart review of a convenience sample. Methods: A total of 220 colts and stallions admitted for sutured castration. Methods: Medical records of sutured castration were assessed for patient characteristics, perioperative and postoperative medications, and postoperative complications within 6 weeks after surgery. The effect of these variables on the occurrence of complications was a...
Antibiotic resistance in equine dermatology: what should we do? Antibiotic resistance is a growing concern worldwide and across species. This is especially important in horses with skin infections, as many of them are infected with Staphylococcus aureus, which can also colonize people. An increasing body of literature has documented colonization of horses with methicillin-resistant S aureus (MRSA) and transmission of MRSA between horses and veterinarians and vice versa. Colonization with MRSA does not always result in disease but has a potential impact on other horses, owners, handlers, and especially veterinarians. The WHO has published criteria to determ...
Misidentification of Raoultella spp. (R. terrigena, R. planticola) and Klebsiella spp. (K. variicola, K. grimontii) as Klebsiella pneumoniae: Retrospective study of a necropsy-associated bacterial collection from horses. Misidentifications as Klebsiella pneumoniae were observed during a French retrospective study of a necropsy-associated K. pneumoniae bacterial collection from horses. Accordingly, the present study aimed to further characterise the 12 Raoultella spp. and Klebsiella spp. strains involved in these misidentifications. The strains were identified and characterised using the Api 20E system, K. pneumoniae PCR detection, matrix-assisted laser desorption/ionisation time-of-flight mass spectroscopy and whole-genome sequencing. Antimicrobial susceptibilities were tested by the disc diffusion method with...
Clinical use of antimicrobial regional limb perfusion in adult horses diagnosed with synovial sepsis or penetrating synovial wounds at a single equine referral hospital in the Midwest United States-163 cases (2010-2020). The clinical outcomes in horses diagnosed with established synovial sepsis (SS) or minimally contaminated synovial wounds (SW)/non-established sepsis, following intravenous regional limb perfusion (IVRLP) treatment, have not been reported since 2010. Additionally, previous reports on this subject were confined to just two clinical retrospective reports. This study aimed to provide an update on the short-term (hospital discharge) and long-term (≥1 year) survival rates in adult horses diagnosed with SS or SW treated with IVRLP at a single institution in the USA from 2010-2020. The study also...
Cutaneous non-tuberculous Mycobacterium ulcerans infection: A serious cause for concern. Mycobacterium ulcerans infection in horses is under-reported. Objective: To document the successful multimodal treatment of M. ulcerans and highlight the need for further investigation due to the zoonotic nature of M. ulcerans with its related potential public health concerns. Methods: Case report CASE DESCRIPTION: A 14-year-old gelding in the Southeastern region of Australia was diagnosed with M. ulcerans infection, initially presenting as a non-healing wound of the right flank progressing to extensive necrotic ulceration. Ziehl-Neelsen and Wade-Fite stained incisional biopsies revealed large...