18 August 1995

Researchers seek to improve the lot of livestock in transit

By Andy Collings

LIVESTOCK transport remains a contentious issue; where animals are taken, how long they are in transit and the conditions in which they travel.

While the first two have become political issues, the latter is being investigated by Silsoe Research Institute.

"The aim of the research is to understand how air moves around and within a transporter as it is driven along the road, and find a system which can maintain a suitable environment," explains project leader, Peter Kettlewell.

But just what a suitable environment is has yet to be defined. Parallel research at Edinburghs Roslin Institute is striving to ascertain what temperature and humidity is best suited to a particular class of livestock.

Meanwhile, Mr Kettlewells research hopes to provide the mechanical means of achieving a specified environment once it has been defined.

Test bed for the project is an articulated lorry, the trailer supplied by transporter maker, Houghtons Parkhouse Coachwork.

Deemed to be a widely used type of transporter, the only concession for the project is that panels are bolted rather than welded to the main frame. This allows sections to be removed or replaced if the research demands it.

"The first point to note when a lorry is travelling along the road is that air flows in from the back and travels forwards," says Mr Kettlewell. "A situation not widely appreciated."

Complex air flow

In fact the flow of air around a lorry on the move is a complex subject. To help glean a greater understanding pressure sensors have been fitted at intervals along the sides of the transporter.

"A moving transporters side panels have low pressure at the front and high pressure at the rear, hence the flow of air into the vehicle from the back," he explains.

But just how much air, its velocity and distribution within the container are questions which need to be answered. And, more importantly, how these factors can be changed or manipulated.

One idea has been presented by the transporters manufacturer Michael Houghton, who has fitted a row of vertical louvres to a length of ventilation grill. This experimental grill section is capable of pivoting open or closing flat and is one way the flow of air into the vehicle can be altered.

"We use a sonic anemometer to detect and measure air velocities at different points within the container," explains Mr Kettlewell. "And we are certainly looking very closely at Mr Houghtons idea."

Other information is collected from a sensor fitted above the tractor unit cab which records the airspeed over the moving vehicle.

"It is important we glean as much information as we can. It is only then we shall be able to make positive recommendations concerning the way air flow can be controlled and the environment managed."

MAFF is funding this SRI research to the tune of £640,000 over four years.