HORSES who suffer from a rare and deadly nerve condition could help scientists better understand Alzheimer’s disease, according to a study.

Scientists claim animals with equine grass sickness show some of the same symptoms as humans suffering from neurodegenerative conditions - a discovery which could lead to clues about the human illnesses.

The research, from the University of Edinburgh’s Roslin Institute and Royal (Dick) School of Veterinary Studies, also sheds new light on the equine condition and could help vets develop new tools for diagnosing the fatal disease.

Dr Tom Wishart, from the university’s Roslin Institute, who led the study, said it showed similar features developing in the diseases.

He said: "This is the first study to show similarities between an apparently unrelated neurodegenerative disease of large animals and human neurological conditions.

“Although the causes of these conditions are unlikely to be shared, the findings suggest that similar mechanisms could be involved in the later stages of disease.”

Researchers from the university looked at nerve tissue from six horses that had died from equine grass sickness in a bid to investigate the causes of the condition.

They found that the horse tissue contained proteins that are commonly seen in the brains of people with Alzheimer’s disease – such as the build-up of amyloid protein.

Dr Wishart said examining the tissue revealed amyloid had built up in the same way it does in patients with neurodegenerative conditions.

He claimed the findings could mean that the protein is not likely to be the cause of such diseases, but a consequence of them, and could help to “unravel clues” about the human conditions.

“When we examined the tissue we found an overlap with diseases in humans such as Motor Neurone Disease and Alzheimer’s,” Dr Wishart said. “Mainly the development of amyloid protein which is most extensively studied in the brainset of patients with Alzheimer’s.

“The study suggests that the build up of the protein is more likely to be a consequence of the breakdown of the cells, rather than the cause, but it is all still speculative at the moment.”

The study, published in the journal of Molecular and Cellular Proteomics, revealed that in total, 506 different proteins were found to be altered in nerve tissue from horses with grass sickness, compared with animals that had died from other causes.

This knowledge could help to develop tests for detecting the condition in horses, which can be tricky to diagnose.

Grass sickness attacks nerve cells in horses but the causes of the disease are unknown.

It causes stomach upset and muscle tremor and can kill within days, however animals diagnosed quickly can sometimes be nursed back to health.

Around two per cent of horses die from the sickness each year in the UK. The disease occurs almost exclusively in grass-fed animals, including ponies and donkeys.

However, a similar condition is thought to affect cats, dogs, hares, rabbits, llamas and possibly sheep.