Smaller dogs may live twice as long life as their larger counterparts. But does this size difference also impact how dogs age in terms of behavior and cognitive abilities? Based on the data of 15,000 dogs, researchers from ELTE Eötvös Loránd University, Budapest, found that larger dogs experience an earlier onset of age-related decline (at around seven-eight years of age versus ten-eleven years in smaller dogs), but also a slower decline rate compared to smaller dogs. Additionally, the study also points out that, although larger dogs have somewhat shorter lifespans, they also maintain their cognitive health longer and experience a smaller degree of age-related decline than their smaller counterparts. 

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