Equine asthma in Brazil – a scoping review

Abstract

Asthma is a chronic respiratory disease that can occur in horses of different breeds and ages. While its occurrence has been reported in many countries, its occurrence across Brazil is unclear. This review aimed to gather information about equine asthma from studies performed in Brazil by different groups and investigate a variety of horse populations. Articles published in peer-reviewed scientific journals, as well as information contained in dissertations and theses, were searched on PubMed, SciELO, Google Scholar, and the Brazilian government catalog of dissertations and theses. Fifteen studies were included in this review, and according to the published information, the authors identified equine asthma using clinical signs, endoscopic findings, and/or cytological examination of tracheal wash and/or bronchoalveolar lavage fluid. Studies have investigated horses of different breeds and activities (racehorses, police horses, riding horses, Crioulos horses, and others) and were performed in different regions with diverse climatic conditions. On the previous observed studies, the occurrence varied from 14.0% to 60.0%, with a mean occurrence of 24% for severe asthma. Other studies must be performed to further understand the occurrence of equine asthma in Brazil, according to different climatic regions.

Pulmonary aspergillosis in a horse: a case report

“…Corroborating the case described by Moreira et al (2004), the initial diagnosis of the horse in this report was equine asthma, a relatively common condition in several regions of the country (Oliveira et al, 2022). In Brazil, a large country with different climatic conditions, several studies have described chronic lung conditions related to the different stages of equine asthma (Melo et al, 2007;Oliveira et al, 2022), resulting in the disease being the main suspect in cases of chronic respiratory disease in sport animals.…”

“…In Brazil, a large country with different climatic conditions, several studies have described chronic lung conditions related to the different stages of equine asthma (Melo et al, 2007;Oliveira et al, 2022), resulting in the disease being the main suspect in cases of chronic respiratory disease in sport animals. The classic manifestation of equine asthma varies from exercise intolerance to dyspnea during rest, in addition to chronic cough, mucous to mucopurulent nasal discharge (Melo et al, 2007;Oliveira et al, 2022), findings compatible with those reported by the owner in the present report and also present in cases of fungal pneumonia (Higgins & Pusterla, 2006).…”

“…In the case reported, neutrophils corresponded to less than 4% of the cells in the tracheal lavage, excluding asthma as a possible cause of the clinical signs presented by the horse. The tracheal wash technique is well described and is widely used for diagnosing inflammation in the lower airways (Oliveira et al, 2022), and shown to have greater sensitivity and specificity for detecting increased quantities of neutrophils in airways than BAL (Rossi et al, 2018).…”