Flea – Life Cycle

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Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that survive as external parasites of mammals and birds.
Fleas live by consuming blood or hematophagy, from their hosts.
Fleas are holometabolous insects, going through the four lifecycle stages of egg, larva, pupa (cocoon), and imago (adult).


FLEA LIFE CYCLE I Love Veterinary - Blog for Veterinarians, Vet Techs, Students


  • The adult flea feeds from the host’s blood.
  • After 2 days, the flea will lay eggs. The eggs fall from the coat to the environment.

  • After 2 days, the eggs hatch into a first stage larva.
  • The first stage larva molts into a second stage larva and then into a third stage larva.
  • The third stage larva makes a cocoon that later hatches an adult flea.