'The Fox and the Duck' is another one of the few 1945 Terrytoons to not feature a re-curring character, in a year dominated by Gandy/Sourpuss and especially Mighty Mouse cartoons. As has been said, it is the second cartoon in the Aesop Fables series revival, and am glad that was mentioned because that is what it felt like when watching without doing any prior research so appreciate that that was clarified.
As far as the 1945 Terrytoons go, 'The Fox and the Duck' is one of the middling efforts, indicating a cartoon that is not bad but doesn't have an awful lot special to it. As far as the studio's output goes, it is firmly in the average middle-of-the-road group, in a very variable but oddly interesting output that lasted from 1930 all the way through to 1971, a surprisingly long time and am surprised if to honest that it lasted that long. Not meaning that in a derogatory or disrespectful way, despite how it sounds, but all the different years' batches were so hit and miss every year and there were re-curring characters that didn't do much for everybody, in my mind the best faring were Heckle and Jeckle. Gandy took some getting used to and he got much better when partnered with Sourpuss, know people that don't see Mighty Mouse's appeal (others do, am mixed on him myself) and some of the later re-curring characters (i.e. Clint Clobber) didn't do anything for me.
Back to 'The Fox and the Duck', visually and audibly it is great. The animation is vibrant, beautifully detailed in the backgrounds and the smoothness and ambition of the drawing has come on immensely. The music is blameless, the amount of energetic character it is truly endears and the orchestration is lush and clever.
Some amusing moments, some charm, some energy and the fox is a fun character.
Didn't care for the duck as much, not as compelling a personality, a bit annoying actually, and it was disconcerting that the character was like Gandy recycled when at this point there were not as much recycling, repetition or cutting corners visually (can't always say the same for the material). The story is not always particularly engaging and has very little to it, the conflict in need of more tension.
Gags are not enough and they are rather corny and tired. The ending is notable somewhat but done with not an awful lot of subtlety.
In conclusion, average but it at least an alright watch. 5/10