Small dogs live twice as long as big pooches - but age far more rapidly.
Small dogs live longer than their larger counterparts
Experts at Eotvos Lorand University in Budapest recommend getting pet dogs that weigh between 10 and 30 kilograms - breeds such as Whippets, Staffordshire Bull Terriers and Schnauzers.
Previous research has shown that little canines live longer but in this case the experts set out to understand how size impacts dogs in terms of cognitive ability.
The team analysed data on 15,000 dogs and found that those weighing over 30kg showed an earlier onset of age-related decline but a slower rate of cognitive decline.
Borbala Turcsan, lead author of the study, said: "Larger dogs experience a physical breakdown at an earlier age, and the accumulating illnesses, and degradation in sensory functions leads to 'old-age behaviours' long before their mental decline would begin."