Quote:The research compared abandoned dogs rescued from Fukushima with non-disaster affected dogs abandoned in 2009 and 2010, before the earthquake. The dogs that lived through the disaster had stress hormone levels five to 10 times higher than the dogs that were simply abandoned or found as strays. Source
They compared how the dogs hormones reacted with unfamiliar people. They also took into account who between the Kanagawa and Fukushima dogs were more difficult to train and were less attached to their caregivers.
They found out that the cortisol level of dogs that were affected by the disaster were 10 times higher (even after being taken care/rehabilitated for 10 weeks).