Which is the first animal to orbit in space?

Laika, a stray dog, was sent into orbit by the Soviet Union in 1957 aboard the satellite Sputnik 2 (nicknamed "Muttnik" in the US).
Laika, a stray dog, was sent into orbit by the Soviet Union in 1957 aboard the satellite Sputnik 2 (nicknamed "Muttnik" in the US).