Mange is a highly contagious skin disease caused by one or a combination of several species of mites affecting both domestic animals and humans. Mange in cattle is mainly caused by mites, microscopic relatives of spiders which in habit and damages the skin of the animals.
Since the disease is carried by parasites inhabiting both domestic and wild animals, it’s either carried out by any of the host. Although the surface mite is the most common species affecting cattle, there are other species which include burrowing mite and the sheep scab mite. The surface mite usually found on the neck, legs and tail head produces limited hair loss which increases gradually in size. However, the lesions are very itchy which results in hide damage as the affected cattle try to rub the affected areas.
The sheep scab mite is found on the flanks and around the tail head and anus. Although this mite feeds on the surface of the skin, its’ mouthparts pierce the skin, producing blisters that are very irritating. The burrowing mite prefers the neck and the loin area next to the tail. As they burrow into and out of the skin they produce a much more intense irritating reaction causing the skin damage rapidly with many large areas being affected and the skin becoming very thickened and crusty.
Mange may lead to considerable economic losses in domestic animals with repercussions for the animal trade. Infection of the damaged areas often develops and affected animals have much reduced production. Secondary bacterial infections are common in severe cases. In some severe cases, death in untreated calves, weight loss, decreased milk production, and increased susceptibility to other diseases can occur.
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The surface mite and the sheep scab mite both spend their entire life cycle on the surface of the skin. They have a high multiplication rate with the one female able to lay about 90 eggs which once hatched takes only ten days to develop into mature adults. The burrowing mites’ life cycle is complex with the female tunneling into the hosts’ skin and laying about 50 eggs. The eggs then hatch in about five days each releasing a larva. Some of them tunnels to the surface to become adults while others develop in the tunnels with the process taking about two weeks. More tunnels are often formed during the mating process.
For all the three species, infection is spread mainly by direct contact among infected cattle. The burrowing mite can survive for some time off the host body and therefore for this species, bedding and other objects that come into contact with infected animals may become contaminate and help spread the infection.
Treatment for infected cattle is available through use of various products with the choice mainly depending on whether a farmer wants to use pour-on products or injections. The pour-on products are always easier to use as well as affordable as opposed to the injection options. However, in severely infected animals, the skin reaction can mean that contact between the product and the mite is limited.
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In such cases, scabs may have to be removed before treatment. If very severe then injectable products are preferred. For a very severe surface mite problem, an injection should be followed up by a pour- on treatment when the skin has recovered as in this species unlike in burrowing mite, injections only control but do not eliminate.