It’s always fun watching how animators manage to change a character’s shape into something else. It can be elaborate. One problem: elaboration costs $$$. So cartoon studios used a cheaper way of doing it. Most of the time, it looks tacky.
Here’s an example from the cost-saving Walter Lantz studio’s ‘Hot Noon’ (1953). The sheriffs don’t really morph into chickens, though that’s the gag. Instead, cycle animation of sheriffs and cycle animation of chickens are gradually superimposed on each other, with the former fading away.
The animators on this cartoon were Gil Turner, La Verne Harding and Bob Bentley.