Rudi howled, feeling isolated, mainly because he [i]was[/i]. Luckily, Sabrina's cage was adjacent to his, so he could watch over her. She had been out for 2 days and 11 hours. He knew she would wake soon. 
The deep cut in his chest made it hard for Rudi to breathe, so he struggled to howl. But he continue howling, in the hopes that Sabrina would hear the sound and wake up.