and the pets were subsequently euthanized which, according to the Centers of Disease Control and Prevention, was necessary to test for rabies.[3][6][7][8] Longo said that they were in the process of filing paperwork to have the squirrel certified as an educational animal when Peanut was seized.[4] He later stated that the decision to kill the squirrel "won't go unheard."[9]
https://en.wikipedia.org/wiki/Peanut_(squirrel)#Death
If a rabies vaccine cures rabies after a bite then you do not need to euthanize just vaccinate it