Bugs Bunny's scream at the end of the "Tales of the Vienna Woods" segment is actually Fay Wray's, taken from O Monstro (1932).
This short film does not feature Mel Blanc's voices.
The only cartoon in which Porky Pig hunts Bugs Bunny (not counting Porky's Hare Hunt (1938), the first cartoon to feature the rabbit character eventually known as Bugs).
For some reason, the identity of the black duckling in this short has prompted much debate among cartoon fans as to whether or not it is in fact Daffy Duck. Supporters of the idea claim it is Daffy due to the character's similar color design (such as the white band around the neck), while naysayers say that if it was supposed to be Daffy then it would have been made a little more clear in his appearance or by having him speak. It should be noted that the books about Warner Bros. animation history have never addressed this, nor has it ever been confirmed either way. In the Looney Tunes Golden Collection DVD commentary given by Michael Barrier, he claims that it is Daffy, but since he was not a member of the crew who worked on the cartoon nor citing a source as basis for his conclusion, such a declaration should not be taken as absolute fact.
The juvenile Daffy Duck is labeled "4-F." The 4-F classification, under the U.S. Selective Service System, meant that a potential draftee was unfit for any military service, usually for medical reasons.