Is it permissible to raise a stray and emaciated dog out of mercy and care for it until its owner is found or it is adopted, especially since it is not a guard or hunting dog?

One should be kind to a dog by feeding it and providing it with medical care. However, this can be done without owning it and bringing it into the house. It is not permissible to pick up a dog if it is not permissible to own it.

It is recommended to kill a pure black dog, and it is obligatory to kill a rabid dog. As for a owned dog, it is not permissible to kill it.