Balantidium

Balantidium from a pig - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona

Balantidium trophozoite from a pig - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona

• Ciliate protozoan found as a commensal in the lumen of the large intestine

• Infects pigs and other animals
  • Including humans

Recognition

• Ciliate

• 80μm long

• Funnel-shaped depressions leading to the cytostome (mouth)

• Kidney shaped macronucleus

• Small micronucleus

• Contractile and food vacuoles

Life Cycle

• Reproduce by binary fission

• Thick-walled cysts pass out with faeces
  • Ensure infection of a new host

Pathogenesis

• Pigs
  • Usually commensal
  • May cause ulceration and dysentery if the intestinal mucosa is damaged already as parasite will become invasive

• Man
  • Causes ulceration and dysentery
  • Infection via consuming contaminated foodstuffs and contact with infected pig faeces