Pet owners may envy their pampered pooches lying around the house snoring and yawning with abandon, but now scientists have warned that bestial boredom could cause animals' brains to shrink.
Research has indicated that dogs become distressed by chronic boredom and can suffer adverse effects from a lack of stimulation.
Cattle and animals in zoos can also suffer if they are kept in dull surroundings with little to interest them, it is claimed.
Animal welfare lecturer Charlotte Burn, from the The Royal Veterinary College, used cameras to observe dogs left alone in houses before publishing an essay called "Bestial boredom: a biological perspective on animal boredom and suggestions for its scientific investigation."
She told The Times: “They often yawn, bark, howl and whine. Some sleep a lot – a sign of apathy. Some of this is anxiety but often they are just really bored.
“Boredom has long been thought of as a solely human emotion but animals suffer from it too. Research shows that being kept in barren environments without stimulation damages the brain.
"Neurones die off if not stimulated, so the brains of such animals tend to be smaller with fewer synapses.”
Ms Burn said "wild and domesticated animals are at particular risk in captivity, which is often spatially and temporally monotonous" in her paper, which was published in the journal Animal Behaviour.
“Human prisoners describe boredom as a torment and a monster that takes them over," she told The Times.
"They get cognitive deficits eventually, and so do animals. It is true suffering, especially when prolonged and inescapable, as happens on modern farms. Stimulation for animals, like humans, is not a luxury but a necessity.”
Farm animals confined in sheds rather than being reared in fields may suffer the most from chronic boredom, the research suggests.
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