Lifecycle of Sarcoptic Mange

Sarcoptic mange is a skin disease caused by the Sarcoptes scabei mite. While they sometimes live on humans and other animals, the mites prefer to live on dogs. Called canine scabies, the arthropod invades the skin of healthy dogs and creates problems. Common symptoms include hair loss and itching, but several good treatments make the disease easily controllable.

  1. Hosts

    • Scabies will live on humans as well as both wild and domestic dogs, cats and bears. In North America, you often find them on red fox, wolves and coyotes. In wild animals, the mange usually affects younger animals. Mites burrow beneath a layer of dog or puppy skin and stay there, causing hair loss, scabs, rashes and itching for the length of their stay.

    Transmission

    • Highly contagious, mites can transfer and infect a host at any stage of development. Usually, direct body contact is required for an infection to occur. Infected inanimate objects can transfer mites as well. Specific populations adapt to their hosts, so human-adapted populations travel faster through humans. According to Pet Education, "because of the mite's ability to survive off (away from) the host, dogs can become infected without ever coming into direct contact with an infected animal."

    Reproduction

    • Male and female mites get onto the dog's skin and breed before the female burrows under the skin. The female goes a least half an inch and lays eggs as it digs the trail. Sometimes, a female will make a tunnel a couple inches long before dying. The female mite dies after depositing the eggs, which hatch in three to four days.

    Larvae and Nymph Stage

    • After hatching, larvae crawl through the skin to the surface and become adults in two weeks. At the first stage, larvae have six legs, but then they mature into nymphs with eight legs. At the end of the burrow, nymphs molt and become adults. They eat skin cells throughout the entire process.

    Mites

    • Microscopic mites are not insects. In fact, they are closer to spiders. They usually live three or four weeks inside the host's skin. The entire life cycle takes about two to three weeks. Males mature in 13 to 16 days and females mature in 18 to 23 days, with fertilization occurring during the female's final development stage.