New research from Japanese scientists suggests that a dog’s eyes may well up with tears of happiness when reunited with its owner after a period of absence. Tears in dogs have not been linked with emotion before.
We found that dogs shed tears associated with positive emotions . . . oxytocin was discovered as a possible mechanism underlying it . . . “ – Takefumi Kikusui
Source: CNN, August 22, 2022. Link.
Also see: Increase of tear volume in dogs after reunion with owners is mediated by oxytocin, Current Biology, July 31, 2022. Link.