White mice were in big demand at the time, usually by medical labs.
The score for this cartoon was featured on the audio CD "Tom & Jerry & Tex Avery Too!".
As is common in the cartoons of this era, careful attention is paid to the background. Everything from a garden hose to a sewing basket to a glass dish of fresh fruit to venetian blinds is drawn in perfect detail.
Jerry does an old fashioned fan dance to hide his non white areas. Such performances have long been a favorite of exotic dancers.