- Burro: The Brazilian donkey is a breed of donkey known for its hardiness and surefootedness.
- Boi: The Brazilian ox or bull is a type of cattle commonly found in the country and used for meat and dairy production.
- Borboleta: The Brazilian butterfly, which can be found in a wide variety of shapes, sizes, and colors.
- Baleia: The Brazilian whale, including species like the humpback whale, sperm whale, and minke whale.
- Boto: The Brazilian pink dolphin or Guiana dolphin, a species of freshwater dolphin found in the Amazon River system.
- Bagre: The Brazilian catfish, which is a type of freshwater fish found in rivers and lakes across the country.