Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
A case control study of factors and infections associated with clinically apparent respiratory disease in UK Thoroughbred racehorses.
Abstract: A matched case control study was used to determine infections and other factors associated with clinically apparent respiratory disease in young racehorses in training in the UK. A total of 170 cases, defined as horses with sudden onset coughing, nasal discharge or pyrexia, were identified and matched to 632 non-affected controls by trainer and time period. Factors examined included age, sex, time since entry into the training yard, time since last race and different infections including tracheal and nasopharyngeal (NP) bacteria and viruses. Multivariable conditional logistic regression (CLR) modelling was used to evaluate the risk of being a case for variables after adjustment for other factors. Three analyses were conducted using clinical cases as outcomes, which were compared with: (i) controls without evidence of subclinical inflammatory airway disease (IAD) (ii) controls with evidence of subclinical IAD and (iii) all controls irrespective of IAD status. A fourth analysis was conducted comparing the two groups of controls, i.e. those with and without IAD. Younger horses and those that had entered training more recently were at increased risk of suffering episodes of clinically apparent respiratory disease. Among the infections, increasing numbers of Pasteurella/Actinobacillus spp. in tracheal washes were associated with increasing risk of clinical disease. Tracheal infection with Streptococcus zooepidemicus was associated with both clinical respiratory disease and subclinical IAD when compared with controls with no evidence of IAD. This explained the lack of association between clinical cases and S. zooepidemicus when all controls were used. Tracheal isolation of Mycoplasma felis was also associated with clinical disease after controlling for other factors. An inverse association was identified between risk of clinically apparent disease and isolation from tracheal washes of the transient, non-pathogenic bacteria Staphylococcus and Acinetobacter spp. There was no significant association identified between clinical disease and infection with equine herpesviruses-1 and -4, rhinoviruses-1 and -2 or adenovirus. Equine influenza was significantly associated with clinical respiratory disease but it was a very rare infection in this well-vaccinated population, only occurring in three cases.
Publication Date: 2003-08-06 PubMed ID: 12900152DOI: 10.1016/s0167-5877(03)00085-0Google Scholar: Lookup The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This study was conducted to identify infections and other factors related to visible respiratory illness in young racehorses in the UK. The findings revealed that younger horses and those newer to training were at greater risk of visible respiratory disease, with various bacteria linked to higher risks of illness.
Overview of the Research Methodology
- This investigation was conducted using a matched case-control study, an observational method that analyzes two existing groups differing in outcome to identify factors associated with the variation.
- The study involved a total of 170 cases, defined as horses showing sudden coughing, nasal discharge, or fever. These cases were matched with 632 unaffected controls based on their trainer and time period.
- The parameters tested included age, sex, period since admission into the training yard, time since last race, and various tracheal and nasopharyngeal (NP) bacterial and viral infections.
- Advanced statistical techniques (multivariable conditional logistic regression modelling) were used to measure the risk of the studied variables after adjusting for other factors.
Key Outcomes and Findings
- Younger horses and those that started their training recently were found to be at higher risk of presenting with visible respiratory disease.
- Among infections, the number of Pasteurella/Actinobacillus spp. bacteria found in tracheal washes proportionally impacted the risk of clinical disease.
- The study noticed a relationship between Streptococcus zooepidemicus tracheal infection with both visible respiratory disease and latent Inflammatory Airway Disease (IAD). However, no correlation was observed between study cases and S. zooepidemicus when all controls were involved, due to the former connection.
- The presence of Mycoplasma felis was also associated with visible disease after adjusting for other parameters.
Infections & Disease Risk
- An inverse association was found between Staphylococcus and Acinetobacter spp., transient non-pathogenic bacteria, and the risk of clinically apparent disease.
- No significant association was observed between visible disease and equine herpesviruses-1 and -4, rhinoviruses-1 and -2 or adenovirus infections.
- Although equine influenza showed correlation with visible respiratory disease, it was seldom seen in this well-vaccinated population.
In summary, this research provides essential information regarding the conditions that increase the risk for developing respiratory diseases in racehorses, useful knowledge for trainers and handlers to manage and prevent outbreaks efficiently.
Cite This Article
APA
Newton JR, Wood JL, Chanter N.
(2003).
A case control study of factors and infections associated with clinically apparent respiratory disease in UK Thoroughbred racehorses.
Prev Vet Med, 60(1), 107-132.
https://doi.org/10.1016/s0167-5877(03)00085-0 Publication
Researcher Affiliations
- Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU, UK. richard.newton@aht.org.uk
MeSH Terms
- Animals
- Bordetella Infections / microbiology
- Bordetella Infections / veterinary
- Case-Control Studies
- Female
- Herpesviridae Infections / veterinary
- Herpesviridae Infections / virology
- Horse Diseases / etiology
- Horse Diseases / microbiology
- Horses
- Logistic Models
- Longitudinal Studies
- Male
- Multivariate Analysis
- Pasteurella Infections / microbiology
- Pasteurella Infections / veterinary
- Picornaviridae Infections / veterinary
- Picornaviridae Infections / virology
- Respiratory Tract Diseases / etiology
- Respiratory Tract Diseases / microbiology
- Respiratory Tract Diseases / veterinary
- Streptococcal Infections / microbiology
- Streptococcal Infections / veterinary
- Trachea / microbiology
- United Kingdom
Citations
This article has been cited 14 times.- Junkkari R, Mykkänen A, Sulku P, Rantala M, Pohjanvirta T, Eklund M, Pelkonen S, Grönthal T. Occurrence, antibiotic susceptibility and genetic variation of Streptococcus zooepidemicus in Finnish weanling horses with and without respiratory infection. Acta Vet Scand 2026 Jan 27;68(1):7.
- Jurisic L, Auerswald H, Marcacci M, Di Giallonardo F, Coetzee LM, Curini V, Averaimo D, Ortiz-Baez AS, Cammà C, Di Teodoro G, Richt JA, Holmes EC, Lorusso A. Insect-specific Alphamesonivirus-1 (Mesoniviridae) in lymph node and lung tissues from two horses with acute respiratory syndrome. J Virol 2025 Feb 25;99(2):e0214424.
- Cullinane A, Garvey M, Walsh C, Gibbons J, Creighton A. A Scoping Review of Non-Structural Airway Disease as a Cause of Poor Performance in Racehorses. Animals (Basel) 2023 Jan 27;13(3).
- Lo Feudo CM, Stucchi L, Conturba B, Stancari G, Ferrucci F. Impact of Lower Airway Inflammation on Fitness Parameters in Standardbred Racehorses. Animals (Basel) 2022 Nov 21;12(22).
- Nielsen SS, Alvarez J, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortázar C, Herskin M, Michel V, Miranda Chueca MÁ, Roberts HC, Padalino B, Pasquali P, Spoolder H, Ståhl K, Calvo AV, Viltrop A, Winckler C, Carvelli A, Paillot R, Broglia A, Kohnle L, Baldinelli F, Van der Stede Y. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): infection with Equine Herpesvirus-1. EFSA J 2022 Jan;20(1):e07036.
- Lo Feudo CM, Stucchi L, Alberti E, Stancari G, Conturba B, Zucca E, Ferrucci F. The Role of Thoracic Ultrasonography and Airway Endoscopy in the Diagnosis of Equine Asthma and Exercise-Induced Pulmonary Hemorrhage. Vet Sci 2021 Nov 15;8(11).
- Payette F, Charlebois A, Fairbrother JH, Beauchamp G, Leclere M. Nicoletella semolina in the airways of healthy horses and horses with severe asthma. J Vet Intern Med 2021 May;35(3):1612-1619.
- Bond SL, Workentine M, Hundt J, Gilkerson JR, Léguillette R. Effects of nebulized dexamethasone on the respiratory microbiota and mycobiota and relative equine herpesvirus-1, 2, 4, 5 in an equine model of asthma. J Vet Intern Med 2020 Jan;34(1):307-321.
- Rossi TM, Moore A, O'Sullivan TL, Greer AL. Equine Rhinitis A Virus Infection at a Standardbred Training Facility: Incidence, Clinical Signs, and Risk Factors for Clinical Disease. Front Vet Sci 2019;6:71.
- Junkkari R, Simojoki H, Heiskanen ML, Pelkonen S, Sankari S, Tulamo RM, Mykkänen A. A comparison of unheated loose housing with stables on the respiratory health of weaned-foals in cold winter conditions: an observational field-study. Acta Vet Scand 2017 Oct 26;59(1):73.
- Léguillette R, Tohver T, Bond SL, Nicol JA, McDonald KJ. Effect of Dexamethasone and Fluticasone on Airway Hyperresponsiveness in Horses With Inflammatory Airway Disease. J Vet Intern Med 2017 Jul;31(4):1193-1201.
- Couëtil LL, Cardwell JM, Gerber V, Lavoie JP, Léguillette R, Richard EA. Inflammatory Airway Disease of Horses--Revised Consensus Statement. J Vet Intern Med 2016 Mar-Apr;30(2):503-15.
- Kusano K, Ishikawa Y, Seki K, Kusunose R. Characteristic of inflammatory airway disease in Japanese thoroughbred racehorses. J Equine Sci 2008;19(2):25-9.
- Wood JL, Newton JR, Chanter N, Mumford JA. Association between respiratory disease and bacterial and viral infections in British racehorses. J Clin Microbiol 2005 Jan;43(1):120-6.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
