Botfly

A botfly is a type of fly.

Its babies live inside other animals. Some grow in skin. Others grow in bellies.

Female flies lay eggs on insects. They might use a tick. The eggs hatch when they feel warmth.

The babies burrow into the skin. They stay there to grow. This can make the animal feel itchy.

Some babies grow for many months. They eventually fall out into the dirt. New flies grow from them.

These flies do not kill their hosts. They are just guests that stay too long.

A botfly is a type of fly in the family Oestridae.

Most botflies have larvae that live inside mammals. A larva is a maggot. Some maggots grow in the flesh of an animal. Others grow inside the gut, which is the belly area.

Female botflies have a clever way to lay eggs. They often use an intermediate vector. This is a middle insect like a mosquito or a tick. The female fly holds onto the insect with her legs. She attaches 15 to 30 eggs to its body. She does this many times. She can lay up to 400 eggs in her short life.

When the eggs feel warmth, they hatch. The maggots drop onto a large animal. They burrow under the skin to grow. These flies do not kill their hosts. They are parasites that live off the host. In horses, the larvae can stay for 10 to 12 months. They finally fall out in the animal's waste. Then, new adult flies emerge from the soil.

Botflies belong to a family of insects called Oestridae.

People call them by many names like warble flies, gadflies, or heel flies. The word "bot" actually means a maggot. These flies are interesting because their larvae are internal parasites. This means the young flies live inside the bodies of mammals. Some species grow deep within the animal's flesh. Other species live inside the alimentary tract, which is the gut.

There are roughly 150 known species of botflies found worldwide.

The way these flies reproduce is very clever. A female botfly has a short adult life of only 8 to 9 days. During this time, she can produce between 100 and 400 eggs. She often uses an intermediate vector to help her. An intermediate vector is a middle insect like a mosquito or a tick. The female fly grabs the insect with her legs. She attaches 15 to 30 eggs to the insect's abdomen.

When the eggs feel the warmth of a large mammal, they hatch. The larvae then drop off and burrow under the skin.

Different species affect different animals in unique ways. Equine botflies lay eggs on horses. These eggs look like small, yellow drops of paint. They often sit on the horse's legs or nose. If a horse rubs its nose on its legs, it might swallow the eggs. The larvae then grow inside the horse's intestines. They stay there for 10 to 12 months.

Eventually, the reddish-orange larvae are passed out in the animal's feces. They then pupate in the soil to become adults.

Some botflies are known to interact with humans. The species Dermatobia hominis is the only one that routinely parasitizes people. In cattle, these flies can cause problems like lechiguana. This is a condition where hard lumps grow under the skin. These lumps are caused by a bacterium called Mannheimia granulomatis. Without antibiotics, an affected animal might die within 3 to 11 months. Other flies, like the mouse botfly, live in North America. This species specifically targets small mammals.

Humans have even had long histories with these insects. In cold places, people have eaten botfly larvae. For example, the Inuit people have historically eaten them. In a show called Beyond Survival, Les Stroud watched Inuit guides eat a larva. He noted that the larva tasted like milk. This practice is also seen in very old art from the Pleistocene era in Europe. Even the Babylonian Talmud discusses if these flies are kosher. This shows how these small insects have always been part of human stories.

Botflies are a group of insects belonging to the family Oestridae. They are known by several different names, including warble flies, gadflies, and heel flies. The term "bot" is actually a word used to describe a maggot. These flies are unique because their larvae are obligate internal parasites. This means the young larvae must live inside the bodies of mammals to survive. Some species grow directly within the flesh of their hosts. Other species live inside the alimentary tract, which is the host's digestive system.

The life cycle of a botfly involves several specific steps to ensure survival. A female botfly has a very short adult life, lasting only 8 to 9 days. During this brief time, she can produce between 100 and 400 eggs. To distribute these eggs, she often uses an intermediate vector. A vector is a middle insect, such as a mosquito, a housefly, or a tick. The female fly captures the vector by holding its wings with her legs. She then attaches 15 to 30 eggs to the abdomen of the insect.

When these eggs come into close proximity to a large mammal, the host's body heat stimulates them to hatch. The larvae then drop off the vector and burrow under the animal's skin. In some cases, eggs are deposited directly onto the skin of a large animal. Other species involve the larvae being ingested through licking. Once inside, the larvae develop within the host. They do not kill the host, which is why they are classified as true parasites. After they reach maturity, the larvae drop from the host and complete their pupal stage in the soil.

Different species of botflies target different animals in specific ways. Equine botflies, for example, affect horses by laying eggs on the legs or the nose. These eggs look like small, yellow drops of paint and adhere to the horse's hair. If a horse rubs its nose on its legs, it can transfer the eggs to its mouth. From there, the eggs move to the intestines. The larvae grow there for 10 to 12 months, attaching to the stomach or small intestine lining. This attachment causes irritation, erosions, and ulcerations.

In cattle, botfly infestations can lead to more serious medical issues. The lesions caused by these flies can become infected by a bacterium called Mannheimia granulomatis. This infection causes a condition known as lechiguana. Lechiguana is characterized by the rapid growth of hard lumps beneath the skin. If the affected animal does not receive antibiotics, it may die within 3 to 11 months. To manage these flies, owners can use various dewormers, such as ivermectin, dichlorvos, or trichlorfon. Other species, like the mouse botfly (Cuterebra fontinella), target small mammals across North America.

Humans have a long and surprising history with these insects. The species Dermatobia hominis is the only botfly known to parasitize humans routinely. However, humans have also used botfly larvae as a food source in certain cultures. In cold climates, populations that rely on caribou or reindeer have historically eaten the maggots. Survival expert Les Stroud observed Inuit guides eating a larva during a hunt on Baffin Island. He noted that the larva tasted like milk. This practice is supported by very old art from the Pleistocene era in Europe.

Beyond simple biology, botflies appear in many different human records. The Babylonian Talmud even includes discussions regarding whether the warble fly is kosher. This shows how deeply these insects are woven into human history and law. There are roughly 150 known species of botflies found throughout the world. While the Oestridae family contains the highest proportion of mammal parasites, other fly families also cause myiasis, which is an infestation of larvae. For example, blow-flies are members of a related family that can also cause similar issues in humans.