Picasso produced animals, birds and insects frequently in oil paintings and pencil sketches, often depicting them in different styles from one artwork to the next. The Rooster here is simplified in terms of form, with colour proving critical to this work.
The artist also carefully sets about producing a feeling of movement which from a static canvas requires skill and creativity. His inclusion of tail feathers are angled in a way as to suggest at this, whilst a viewer's mind and understanding of the bird can fill in the blanks.
The Rooster came in 1943 but the theme had been used by Picasso for around five years at this point. He was demonstrating a desire to take this bird into a different direction in this painting.
When asked about his use of cockerels in multiple works, Picasso pointed at a possible symbolism related to the United States, stating, "...there have always been cocks, but like everything else in life we must discover them - cocks have always been seen but never as well as in American weather vanes..."
As with Cat and Bird, further symbolism may point to war, specfically the futility of it all.