INVESTIGATIONS were being carried out today into the death of around 18,000 chickens which perished while being transported to Hereford's Sun Valley Foods.

Officers from Herefordshire's environmental health department were due to meet the company to examine the incident, which has been blamed on the week's blistering heatwave.

But the company, which said it had transported the birds to its Grandstand Road factory from within the Midlands region, added steps had been taken to stop the blistering heat affecting the chickens.

Mark Sisson, strategic business development director at Sun Valley, said the number of birds held in each cage was the lowest ever, to counteract the effects of the temperatures.

"Although every precaution was taken to minimise losses and help the birds, the sharp rise in temperature and the humidity of the day caught us by surprise," he said.

"There is a very stringent procedure for dealing with hot days. We attempt to maximise ventilation and minimise holding and transit times. Also, the number of birds held in each crate is kept very low and on this occasion was the lowest ever.

"We're looking at ways to ensure this does not happen again."

Mike Higgins, animal welfare manager at Herefordshire Council, said inquiries would be carried out into the Monday incident.

"Should we find these are provable offences we will take the necessary action," he said.

"The offences we will be looking for would involve unnecessary suffering or cruelty during the transportation of the poultry."

A spokeswoman for the RSPCA said that, if the animals were found to have died because of heat, it demonstrated how quickly animals perished in high temperatures.

"We hope this sort of incident would make people think twice when transporting animals in hot weather," she said.

"Everyone with a responsibility of care for animals during transportation must be aware of the effects heat has. This really is a tragedy."