Retrospective study of the relationships between age, inflammation and the isolation of bacteria from the lower respiratory tract of thoroughbred horses

Abstract

A total of 1235 tracheal aspirates taken from 724 thoroughbreds in race training, aged from two to 10 years, were examined cytologically and bacteriologically. An inflammation scoring system on a scale of 0 to 9 was devised to allow the severity of lower airway disease to be assessed from the cytological results. The inflammation scores were closely related to the isolation of bacteria (P<0.001), and the most common bacterial isolates were Streptococcus zooepidemicus, Streptococcus pneumoniae and Pasteurella/Actinobacillus-like species. Lower airway disease was less common in older horses (P = 0.031), and the groups at highest risk were the two- and four-year-olds. Lower airway inflammation was more common in the four-year-olds at National Hunt yards than in the four-year-olds at flat racing yards (P = 0.040, odds ratio = 3.80).

Endoscopic findings, microbiological and cytological evaluation of tracheal aspirates in a population of Standardbred horses with poor performances

“…Furthermore, 10 out of 14 positive horses had cytological evidences of inflammation with the higher neutrophil percentage (81%) associated at the highest bacterial load (7 860 × 10 2 ) in horse number 16. Similar findings in thoroughbred were also reported (Chapman et al, 2000). In horse number 3, with evident endoscopical and cytological signs of inflammation, S. zooepidemicus was the only bacteria isolated.…”

“…Specific association between upper and lower airway disease and S. zooepidemicus was highlighted also by other Authors (Burrell et al, 1996;Newton et al, 2008). On the other hand, several horses with IAD may result negative for culture of respiratory secretion (Chapman et al, 2000) and potentially pathogenic bacteria can be isolated from healthy horses (Sweeney et al, 1985). If the presence of bacteria in the trachea of affected horses indicates a primary infection or a secondary decreased clearance is therefore still unclear.…”

Inflammatory Airway Disease of Horses—Revised Consensus Statement

“…Historically, much research on airway inflammation in racehorses in training has been based on TW cytology 65, 81, 82. An association between TW neutrophilia and cough23 is acknowledged, whereas the lack of an association between TW cytology and poor performance,10 in addition to the poor correlation between TW and BALF cytology29, 83, 84 mean that TW cytology is not considered an appropriate alternative to BALF cytology for diagnostic confirmation or characterization of IAD.…”

Enfermidades do trato respiratório posterior em eqüinos de equitação no Rio de Janeiro: prevalência e aspectos clínico-laboratoriais

“…Ainda em eqüinos Puro-sangue Inglês em treinamento, Burrell (1985) observou inflamação de vias aéreas posteriores em 50% dos animais examinados; Wood et al (1999), em estudo epidemiológico longitudinal no Reino Unido, detectaram uma prevalência de 13,8% de doença inflamatória das vias aéreas (DIVA) e na Inglaterra, Chapman et al (2000) verificaram que cerca de 11,3% dos aspirados traqueais examinados apresentaram alterações compatíveis com doença das vias aére-as posteriores.…”