MANGE AND MITES Mange refers to a skin condition caused by microscopic parasites, called mites (arthropods), which burrow under the skin. Mites have segmented bodies, and although they resemble insects, they actually belong to the spider (Arachnid) family. Although uncommon in cats, there are several kinds that can cause problems; the most common being the ear mite (Otodectes cynotis). Other types of mange which can affect cats are head mange (feline scabies), demodectic mange, and walking dandruff (cheyletiellosis), to name a few. Notoedric Mange An uncommon disease, Notoedric Mange is caused by notoedres cati, a microscopic mite which lives mainly on the outer ear tissues of the cat, and is very contagious. It can, however, spread to the top of the head, neck and legs during grooming. After mating, the female mite burrows under the surface of the cat's skin, forming a small tunnel-shaped swelling, where she lays her eggs. The eggs hatch into larvae in the tunnel, and as they grow, migrate to the skin surface, mate, and begin to burrow down again. The entire life cycle is completed in about two weeks, and is spent entirely on the cat. This disease is highly contagious. Diagnosis Notoedric Mange is spread by direct exposure to an infected animal, and since it is microscopic, special skin scrapes are used to detect it. However, as the mite burrows into the host's skin, a case of severe itching, hair loss, and scaly skin will develop. The cat usually will shake its head in an attempt to try and get relief. As well, the skin will thicken, wrinkle and fold, beginning on the face, neck and ears, possibly moving on to other areas of the body. As fluids begin to ooze from the skin, red scaly sores develop, with yellowish crusting on the skin surface. As well, the cat's hair may develop an unpleasant, almost musty odor. This condition should be diagnosed by your veterinarian, who will scrape the surface skin and examine it under a microscope. Notoedric mange appears in kittens as sudden and fierce inflammation, with the abdomen, hindquarters and limbs affected. Left untreated, your cat may experience loss of appetite, emaciation and blood poisoning. Secondary bacterial infection may cause death. Treatment Special miticidal dips are used in the treatment of Notoedres mange; however, since these products are insecticides , they should be purchased from your veterinarian, who will know which product is the safest for cats. As with other external parasites, ALL other pets in the household should be treated, due to Notoedres mange's highly contagious nature. In order for effective treatment, hair around infested regions should be clipped away. Gently soaking with warm water and mild soaps will help loosen the crust, and in a case where the skin is severely infected, your veterinarian may prescribe antibiotics and low doses of cortisone to relieve the itching. It is important to wash the cat's bedding, vacuum all carpeted areas and thoroughly clean the cat's environment. Throw the vacuum bag away. Sarcoptic Mange This type of mange is extremely rare in cats, and tends to infect cats with suppressed immune systems. Also called head mange or feline scabies, the mites that cause this type of mange (Sarcoptes scabiei mites), are larger than the mites that cause Notoedric Mange, and prefer lightly-haired areas. The sarcoptes scabiei mite lives in the cat's skin for three to four weeks. The female mite burrows into the skin after mating, and deposits three or four eggs in the tunnel she has made. Within three to ten days, the eggs hatch as larva, which moves on the skin surface. The larva molts into the nymph stage, and finally into an adult. Diagnosis Due to the close proximity to nerve endings, intense itching occurs. Other signs include red scaly sores, thickening of the skin and hair loss. Since it is microscopic, diagnosis must be made by your veterinarian, who will take special skin scrapes, which he/she will then examine under a microscope. Treatment As with Notoedric Mange, special miticidal dips are used in the treatment of Sarcoptic mange; however, since these products are insecticides , they should be purchased from your veterinarian, who will know which product is the safest for cats. As with other external parasites, ALL other pets in the household should be treated, due to sarcoptic mange's highly contagious nature. In order for effective treatment, hair around infested regions should be clipped away. Gently soaking with warm water and mild soaps will help loosen the crust, and in a case where the skin is severely infected, your veterinarian may prescribe antibiotics and low doses of cortisone to relieve the itching. It is important to wash the cat's bedding, vacuum all carpeted areas and thoroughly clean the cat's environment. Throw the vacuum bag away. Otodectic Mange Otodectic mange, the most common type of mange found in cats, is caused by Otodectes cynotis, the ear mite, which is usually found deep in the cat's external ear canal, causing the cat to shake its head and scratch its ears violently. Normally, this type of mange only affects the skin of the cat's ears, however, uncommonly, it may also affect the skin on other areas of the cat, such as the head, neck, rump or paws. It can cause such things as partial hair loss, redness, scaling and an itchy rash. This type of mange commonly causes ulceration of the ear canal, and sometimes convulsions. It is thought to be a common cause of seizures in the cat, and is considered contagious. The female lays her eggs, which hatch after a four-day incubation period. The larva hatches and feeds on ear wax and skin oils for approximately one week, then molts into a "protonymph", which will in turn molt into a "deutonymph". This deutonymph, who as yet, has not developed a gender, mates with an adult male. It is only after mating that a gender is developed - if a female results, she will be laden with eggs. The total life cycle from egg to adult is completed in three weeks. Diagnosis Signs of infection are a dry black ear discharge resembling coffee grounds. This discharge is made up of ear wax, blood, and the ear mites themselves. In some instances, diagnosis is made simply by the presence of the discharge, however, since the mite that causes otodectic mange is microscopic, diagnosis must be made by your vet. Treatment As otodectic mange infection is highly contagious, it is important to treat all animals in the home. Since ear mite preparations are insecticides, it is important to consult with your veterinarian as to which product to use. Be sure to read the label and follow all directions. Your veterinarian may prescribe antibiotics or imflammatory medications to relieve the itch. It is also important to wash the cat's bedding, vacuum all carpeted areas and thoroughly clean the cat's environment. Throw the vacuum bag away. Demodectic Mange Often called "red mange", demodectic mange is caused by a microscopic mite (Demodex mite), which is a normal resident of the cat's skin and is NOT contagious. Elongated in shape, this mite lives deep in the skin in hair follicles. This type of mange, which is rare in cats, may be localized to the skin on the head, ears, neck and eyelids, or generalized over the whole body of the cat. Cats having the generalized form, may have other immune system suppressing diseases. Transference of this type of mange is not contagious, however can occur from the mother to kittens at birth. Diagnosis Hair loss is the first sign of demodectic mange, usually on the face around the eyes and ears. Cats with severe cases, may have thickened and inflamed skin, due to secondary bacterial infections. Although demodectic mange may not itch, cats with demodex mange may also have scaly, bald regions on the head, legs, and feet. Pus-filled lesions and crusty sores may or may not be present. However, since demotex mites are microscopic, your veterinarian will need to examine skin scrapings under a microscope to make an accurate diagnosis. Treatment Insecticidal cures for demodectic mange have proved very disappointing. Localized lesions tend to respond well to topical treatment by products that exfoliate or strip away layers of skin along with the mite. Generalized cases don't respond as well, and require aggressive veterinary treatment. Recovery depends on the cat's defense mechanism, therefore, the cat must be in good shape for its antibodies to work well. Remember, these treatments are insecticides, and consultation with your veterinarian is necessary. There have been cases where this condition has gone away without treatment. Cheyletiella Mange Cheyletiella (Cheyletiellosis or walking dandruff) is uncommon in cats, is a microscopic mite that lives on the cat's skin, and is considered contagious. They move about rapidly, periodically using their head pincers to attach to the skin in order to feed on tissue fluids, and have been known to be seen crawling in and out of the nostrils. There are three types of Cheyletiella mites which are known to infest cats - Cheyletiella blakei, which is the most common, Cheyletiella parasitivorax, which is common to rabbits, and Cheyletiella yasguri, which is common to dogs. These mites do not burrow underneath the surface of the skin, but live in the keratin of the skin's surface, and may be transmitted both by direct and indirect contact. The female mite lays eggs along the hair shafts close to the cat's skin; the eggs becoming firmly attached to the hair. The life cycle of the Cheyletiella mite is thought to be 35 days, and all stages are completed on the cat. Larvae, nymphs and adult males usually die within 48 hours after leaving the host, while the adult female mites may live off the host for ten days. Diagnosis Characteristic symptoms are crusty, scaly patches (dandruff) on the back of the neck and down the middle of the back to the tail. Slight hair loss and thickening of the skin may also be visible. There are rarely, if ever, lesions on any other part of the body. Upon close inspection, the skin flakes will appear to actually be moving. While the skin may flake or itch, not all cats seem to be irritated by it. Due to the fact that cats are meticulous in their grooming, in some instances diagnosis can be made by your vet via a fecal sample, although often, a microscopic examination of skin flakes or a skin scraping is necessary for diagnosis. Treatment As Cheyletiella mange infection is contagious, it is important that all animals in the home be treated. Since the preparations used to treat Cheyletiella are insecticides, it is important to consult with your veterinarian as to which product to use. Be sure to read the label and follow all directions. Your veterinarian may prescribe antibiotics or imflammatory medications to relieve the itch. It is also important to wash the cat's bedding, vacuum all carpeted areas and thoroughly clean the cat's environment. Throw the vacuum bag away. Lynxacariasis Caused by the lynxacariasis radovski (the cat fur mite), lynxacariasis is an uncommon disease. Attaching itself to the hair shaft, it is thought to spend its entire life cycle on the cat, and feed at the base of the hair. Diagnosis Cats who are infected, have a dull speckled haircoat, which can be easily removed at the root. The cat's skin may be red or scaly in appearance, or show no signs at all. It is necessary to have your veterinarian, who will examine skin scrapings under a microscope make the diagnosis. Treatment Weekly parasiticidal dips or powders for three to four weeks. Trombiculidiasis Trombiculidiasis, is caused by the larvae stage of the Trombicula mite (also known as harvest mites and sometimes called chiggers). Although rare in cats, this condition is difficult to prevent, yet fortunately, easy to treat. The larvae stage of the trombicula mite is visible to the naked eye, appearing as small reddish-orange dots about the size of a pin head, and is usually active during summer and fall, especially in forested and swampy areas. Unlike other mites, chiggers do not burrow under the skin, but attach themselves by piercing the skin around a hair follicle, and injecting fluid that prevents blood from clotting. The female lays her eggs in the soil and around vegetation in late summer. Larvae hatch from the eggs and crawl onto the cat. They attach themselves, and feed on fluids in the tissue for several days, then leave the cat. They then molt into a nymph stage, then mature into adults. The life cycle is completed in 50-55 days. Diagnosis Trombiculidiasis appears on the inside of the cat's ears, head or paws, and may be seen by the naked eye, appearing as small reddish-orange dots about the size of a pin head. Due to the severe itchiness of this condition, look for crusty pus-filled lesions in these areas. Look for the mites in the centre of the lesions. Treatment Special miticidal dips are used in the treatment of Trombiculidiasis; however, since these products are insecticides, they should be purchased from your veterinarian, who will advise you on the best product to use. Also, your veterinarian may prescribe antibiotics or imflammatory medications to relieve the itch.
References: The
Cornell Book of Cats
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