Scientists from the University of Cambridge have shown that, despite being often used as a byword for the mindless mentality of a crowd, sheep have cognitive abilities which rival those of traditional laboratory animals such as monkeys and rats. The findings are important because they may lead to novel approaches to investigating Huntingdon’s Disease, a serious degenerative disease of the brain.

Sheep, both popularly and scientifically, are generally perceived as unintelligent, and so have been excluded when selecting animals to study neurological disorders.  However, when researchers used cognitive tests to examine the extent of their mental capabilities, they were extremely surprised by the learning capacity sheep displayed.

Sheep were repeatedly shown two food buckets: one coloured yellow, the other blue, with food consistently placed in the same bucket.  The sheep learnt which colour of bucket would always contain food after about seven attempts – a rate that is comparable to monkeys and even humans.  Furthermore, when the colour of the food-containing bucket was changed, sheep were able to learn the new rule, once again in a similar amount of time to monkeys and rodents.

Even more surprisingly, sheep showed adeptness at more complex tasks.  They were able to learn the location of food marked by coloured shapes, meaning they had deciphered that the key was shape, not colour.  Professor Jenny Morton, of the Department of Pharmacology, who conducted the research, said “This is a really sophisticated rule change and is generally something that humans take some time to learn. Mice and rats can't do it at all...we can probably classify sheep as being a bit like a slow monkey in terms of intelligence.

The research bolsters anecdotal evidence that sheep can recognise faces and even respond to their own name.  Furthermore, farmers have reported that some sheep in Yorkshire have found a way to cross cattle grids, by rolling onto their backs.

The findings are important because they raise the possibility that scientists could use sheep to study Huntingdon’s Disease.  Huntingdon’s is an incurable and degenerative neurological disease that affects the brain’s cognitive capacity and its ability to control the muscles, leading to writhing movements and dementia.  It is genetic and the children of sufferers have a 50% chance of inheriting the disease gene, but, as sufferers do not tend to show symptoms until their late thirties, many people have children before discovering that they carry the gene.

Mice have often been used to research Huntingdon’s Disease, but they are a poor model as they do not live long enough to show the same cognitive decline as humans.  If sheep with Huntingdon’s can be shown to exhibit dementia-style degeneration, they could be an excellent model for studying the disease.