Balsam Animal Hospital

Most pet owners are quite familiar with common fleas, because these varmints are constantly searching for hosts such as cats, dogs, and other furry creatures.

Once they do find a host, they gorge themselves on the blood of that host until they get their fill. When you see your cat or dog scratching themselves constantly, it's very possible that some fleas have attached themselves to your pet.

To get rid of these pests, it's important to understand the life cycle of a flea, which can vary anywhere from a few weeks to several months, depending on conditions.

Flea eggs

Fleas begin life when a female adult lays her eggs after having gorged herself on the blood of some animal like your pet. It is necessary for the female to fill up with blood before reproducing, and when she does, they will be small, white eggs which are slightly larger than a grain of sand.

These eggs will be laid in your pet's fur, in clusters of about 20, and an adult female can generally produce about 40 eggs in a single day.

These eggs cannot cling to your pet, so they will fall off and be distributed throughout the environment inhabited by your pet. The eggs will take anywhere from two days to a couple weeks to hatch, waiting for ideal environmental conditions before emerging.

When temperatures happen to be cooler and drier, it will take the eggs longer to hatch, whereas when they're warmer and more humid, eggs will hatch much more quickly.

Flea larvae

Larvae which emerge from their eggs are completely blind, and will have a strong aversion to light. Their development will be contingent on eating blood which has been pre-digested, and is passed along by adult fleas, along with other organic material they find in the environment.

Larvae are approximately one fourth-inch long and are nearly transparent, although they appear to be white. When conditions are optimal, these larvae will spin cocoons, generally within 5 to 20 days after hatching from their eggs. This in turn, will lead to the next phase of the flea life cycle, which is the pupae stage.

Flea pupae

This is the final developmental stage before a flea reaches adulthood, and it spins a cocoon which completely envelops it for protection before an adult emerges from it.

When environmental conditions are not favorable for the pupae to emerge, they will remain in the cocoon for up to several months, and in some cases it's even possible for them to stay there for several years.

There is a sticky outer coating on the cocoons which make it possible for them to hide deep within carpeting without being removed by sweeping or even vacuuming.

Somehow, the pupae are aware that the time is not right to emerge from their cocoon until there is a host present. This can be indicated by some kind of vibration, body heat, or increasing levels of carbon dioxide.

Pupae may detect this when your pet walks by, when people circulate throughout the household, or when other signs of life and activity alert the developing adults to emerge and feed on a nearby host.

Adult fleas

When an adult flea finally emerges from its cocoon, it will need to start feeding on a host within a few hours. As soon as it has gorged itself on its initial meal, adult fleas will begin to breed and will lay eggs within just a few days after that.

Adult fleas which have just emerged from the cocoon will have a flat-bodied appearance, and are generally dark in coloration. After feeding off the blood of your pet, they will grow in size and become somewhat lighter in color.

In this stage, an adult flea will spend most of its time living on the host, while feeding, breeding, and laying eggs. It will spend its entire adult life in just a few weeks or a few months living off a host animal in this same manner.

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