India, Oct. 18 -- In March 2011, a huge earthquake and tsunami struck Japan, and a nuclear accident followed in Fukushima. Many families had to flee, and many dogs ended up abandoned, though not by choice. Later, researchers wanted to know how those dogs were doing. A 2012 study in Scientific Reports by Miho Nagasawa, Kazutaka Mogi and Takefumi Kikusui of Azabu University found that 17 dogs rescued from Fukushima had five to 10 times higher levels of urine cortisol than abandoned dogs from another part of Japan. Cortisol is a major stress hormone.

The earthquake on March 11, 2011, was one of the strongest ever recorded. It also resulted in a major nuclear accident. At the time of the paper's publication, some 340,000 people were still di...