Most likely they were killed.
The hunters remained watching the door with feelings of intense anxiety.
The laugh had died upon their lips, as they listened to those hideous sounds, the signs of the fearful combat.

They called their dogs by name.

They hoped to see them issue forth, even if wounded.

But no.
The dogs came not forth--they never came forth--they were dead! A long-continued silence followed the noise of the conflict.

Von Bloom could no longer doubt that his favourite and only dogs had been killed.
Excited by this new misfortune he almost lost prudence.