In 2024, Colleen Lambo began doing boots-on-the-ground veterinary care in Ukraine.

KHERSON, Ukraine — The rescue volunteer holds out his hand, but the dog, stranded on a floating island of debris in a southern Ukrainian city inundated by flooding, is too traumatized to approach.

Russia’s full-scale invasion has torn through Ukraine’s cities and fields, and it has also rewritten the lives of the country’s dogs. Once family pets, village guardians or anonymous strays, they now ...