Crane first injects cows into the narrative, beginning with Henry's mother milking one as he tells her of his decision to enlist in the army, and then bringing them in again, in chapter three, when one soldier tells another that he runs "like a cow." Crane is using the image of a herd animal as a comparison to the soldiers as they stampede from gunfire. In chapter five, Henry feels like "a well-meaning cow troubled by dogs."

Dogs are another animal Crane evokes images of in the narrative. In chapter fifteen, Henry complains about the officers treating the troops "like dogs," emphasizing the idea of their service being a dehumanizing experience. In chapter sixteen, he describes himself as unwilling to behave like "a cat hunted by dogs" and observes the advance and retreat pattern of himself and the enemy as "like a dog" that expects to be followed.

Because Henry and his fellow soldiers are on foot, the horses of the officers which enter the narrative from time to time show the separation of the troops from their commanders. An officer sits astride his "nervous horse" and confers with a general who is also on horseback as soldiers nearby listen to a conversation the troops aren't meant to hear.

Among the animal images that Stephen Crane uses to define the fighting men in The Red Badge of Courage:

• Henry considers himself filled with "eagle-eyed prowess" (Chapter I)
• The new soldiers were referred to as "fresh fish" (Chapter I).
• The narrator described the enemy in the darkness that "moved like monsters" (Chapter II)
• The narrator repeatedly compared the invincible Confederate troops as "dragons."
• The youth saw the troops before him laid out in two long lines like "serpents" (Chapter II).
• The forms of his comrades looked "satanic" in the shadows (Chapter II).
• The Union skirmishers were "busy as bees" (Chapter III).
• Henry was worried that the Confederate troops would kill his comrades "like pigs" (Chapter III).
• War is referred to as the "red animal" (Chapter III).
• Henry also worried that if he cried out a warning to his regiment about the impending onslaught, he would "turn into a worm" (Chapter III).
• The regiment dug into ground "like terriers" (Chapter III).
• The retreating Union soldiers ran like "wild horses" (Chapter IV).
• The colonel of Henry's regiment began to "scold like a wet parrot" (Chapter V).
• Henry compared his "exasperation" as that of a "well-meaning cow worried by dogs" (Chapter V).
• His rage was like a "driven beast" (Chapter V).
• When he turned from the attack, Henry "ran like a rabbit" (Chapter VI).