Monitoring respiratory disease

Researchers at the University of Glasgow have developed  two new non-invasive methods of monitoring respiratory disease in horses.

The number of times a horse coughs provides a good indication of respiratory inflammation - the more inflammation, the more the horse coughs. But it is often not practical, or cost-effective, for someone to physically count the number of times a horse coughs over an extended period.

The research team, led by Professor Sandy Love,  has developed a technique that uses a digital audio recorder attached to the head collar to monitor cough frequency over a long period of time.

In a study to test the value of the technique, the researchers compared audio recordings, each lasting one hour,  with simultaneous video recordings. A total of nine recordings were collected from seven stabled horses .

The  graph of the  audio file could then be examined to identify coughs. Not only was this a rapid process - a  recording lasting one hour could be analysed within three minutes - the technique was also found to be very accurate.

When they compared the audio and video recordings the researchers found that every cough was correctly identified, and no extraneous noises, such as foot stamping,  were mistaken for coughs.
They point out that the speed of the  analysis could be increased further by using  computer software to automate the analysis.

The project also led to the development of a simple device that could be attached to the horse’s head collar to  collect expired moisture. It was used to study the constituents of exhaled breath to see if any could be used as indicators of respiratory inflammation.

The researchers found that the most useful indicator was the pH of the liquid condensed from the expired breath. There was trend toward a reduced pH (acidification) in horses with lower airway inflammation.

The concentration of gases such as carbon monoxide, nitric oxide and ethane was also measured, but the researchers found no correlation between these substances and inflammation in the respiratory tract.

The work was made possible by funding from The Horse Trust . Paul Jepson, Chief Executive and Veterinary Director of The Horse Trust said, “ "We are delighted that the research we have funded has led to new, non-invasive ways of monitoring respiratory inflammation in horses. These techniques could have a major impact on horse welfare by improving the diagnosis and treatment of this common condition.”