Breath sampling for prediction of Rhodococcus equi infection in neonatal foals

Scone Equine Hospital

  • Project code: PRJ-002589

  • Project stage: Closed

  • Project start date: Sunday, June 1, 2008

  • Project completion date: Friday, April 30, 2010

  • National Priority: HOR-Thoroughbred diseases and parasites


This prospective study is investigating whether Rhodococcus equi (R.equi) is exhaled in the breath of neonatal foals on a farm endemically affected by R equi. Utilising a portable air sampling device containing selective agar plates, the respiratory zones of 55 foals between the ages of 2 and 7 days have been sampled throughout the 2007 thoroughbred breeding season. The samples have been bacteriologically cultured, and DNA hybridisation techniques are to be used to detect and quantify virulent R equi in the exhaled breath. Serum samples for detection of passive transfer of immunity were taken from all foals in the sample group at 12-24 hours of age.
Foals were re-examined at 5-6 weeks of age by thoracic ultrasonography, haematology and repeat breath sampling for detection of R equi infection.


Thoroughbred Horses

Research Organisation

Scone Equine Hospital

Objective Summary

The objectives of this project are to determine whether:
1) virulent R equi is detectably exhaled by neonatal foals using a noninvasive, portable air sampling device;
2) the amount of virulent R equi exhaled by neonates, if any, is significant in relation to the overall environmental burden with the organism as detected by the portable air sampler;
3) there is any relationship between the amount of R equi detectably exhaled by neonatal foals and the subsequent development of R equi related disease in individual foals;
4) foals at 5-6 weeks of age detectably exhale virulent R equi; and
5) there is a correlation between the amount of R equi exhaled by 5-6 week old foals and