All mites belong to the Arachnida class of spider-like arthropods. The adults and nymphs have eight legs, and larvae six legs. There is no distinct thorax and abdomen. In fact most superficially resemble balls or discs with a small stalk-like object at the front from which project the mouth parts. The legs vary from short peg-like stumps, consisting of telescoped segments to long hairy appendages. Burrowing mites are peg-legged, spherical, slow-moving types. Non-burrowing mites have legs which usually project beyond the edges of the body. Free-living mites, such as forage or meal mites which are occasional and temporary parasites, have the longest legs. In some mites the feet have suckers, hooks, or both of these structures. The identification of mites can be difficult, even for experts. Parasitic mites vary from between 1/10 and 1 mm. in length according to species. They are thus barely visible unless moving or on a contrasting colored background. A powerful hand lens (xl0) is suitable for mite searching. In some bird species mites are more common than is usually appreciated. Many appear to be harmless passengers, but they can nevertheless carry certain infections including some diseases well known to poultrymen, pigeon fanciers, and a few cage bird breeders. The majority of parasitic species inhabit the surface layers of the body, but some, such as the air sac mites, prefer the protected inner parts of the respiratory system.
The red or roost mite, (Dermanyssus gallinae ):
This poultry mite is a fairly common parasite of many cage birds, especially canaries and other members of the finch family, although budgerigars appear to be quite resistant to its attacks. It affects both perching and ground-roosting birds. It is an agile, gray or brownish long-legged mite which distends and becomes bright red after engorging itself with blood. It is a temporary parasite attacking the bird for short periods, usually at night. After feeding it hides in crevices in perches, the woodwork of the cage or aviary, under the droppings tray in cages, and in fact any dark secluded place. Mites may be brought in by newly acquired stock, or contracted from nearby poultry and wild birds. Apart from restlessness, caused by the nocturnal migrations, the blood-sucking habits of the mites also weaken the birds, especially the young and the old, and eventually produce severe anemia. The plumage may become bedraggled, thin and patchy, which sometimes can lead to feather plucking. When heavy infestations occur, the wholesale desertion of young by parent birds is liable to ruin breeding plans. The anemia often results in loss of weight and leaves the bird susceptible to chilling and infectious diseases. Other parasites such as worms and lice, often multiply under such circumstances and cause further deterioration until the bird becomes too mopey even to preen itself. Red mite infestations often remain unnoticed for months until a large population is present. At this stage, a visit at night with a powerful light suddenly switched on may show myriads of fast moving mites visible as red specks on the birds and neighboring woodwork.
The life cycle is short, the female laying its eggs in cracks and crevices 12-24 hours after its first feed. If the environmental temperature is warm, the eggs may hatch within 48-72 hours to produce larvae. These do not feed but moult into nymphs after 24-28 hours. The nymphs feed on blood, and moult once before eventually moulting to become adults.
HOW TO DEAL WITH THEM
"If you ever see these little bugs crawling on your birds or sucking blood from your chicks, it is terrifying. And no matter what you do, it seems the little bug is out of control, you really call for help.
This situation happened to me in '97. It caused me to shut down my complete breeding program for six months. I lost 20 cockatiel babies because their parents didn't want to go back to the nest box to brooding on their newborn chicks. I went crazy calling people for help and trying different ways to fight the mites. I disinfected everything, threw out all the nest boxes, but the problem still existed.
I have to thank Pat Donnelly for showing me how the finch and canary people prevent the mite problem by dusting the nests and birds with a powder product called "Later's Sevin Garden Dust". He advised me it is very safe for the birds. Because of my problem, I tried this product. I dusted all the cages, the birds and the walls in the bird room. It worked wonderfully for me. The mites were gone in a few days. I repeated this same treatment two weeks later to make sure they were completely gone. Since then, whenever I brought in any new birds I dusted to make sure the mite problem doesn't come back again.
You can get this product from the garden center. It worked for me. I'm sure it will work for you too. Get some and keep it on hand. You don't want to have to use it, but if you need it, this product will fix your problem quickly and may save you a lot of headaches and save your baby birds."
Basic Treatment and Control:
Treatment of the birds alone is useless, because the mites can live away from the host for several months without a feed of blood. The premises therefore should be cleaned thoroughly. All nesting and other disposable material should be burned. Paint surfaces can be repainted with a paint impregnated with an acaricide and all cracks and crevices should also be sprayed thoroughly with a suitable acaricide. Spraying or dusting of the birds themselves may be helpful, but constant vigilance is necessary to prevent a recurrence. It is often impracticable to clean and paint the entire establishment at one time, but even if done sectionally and consecutively over 1 to 2 weeks the effect is almost as good. Acaricides, such as malathion, gamma benzene hexachloride and derris root are effective alone or in combination.
A proven cure myself & others have used is to dust the nests and birds with a powder product called "Later's Sevin Garden Dust". Repeat after 2 weeks. It is wise and a good preventative to do this again whenever you bring in new birds to your bird room.
Northern Feather Mite (Ornithonyssus or Liponyssus sylviarum) & Tropical Feather Mite (0. bursa):
The habits, and therefore the treatment, of these mites are similar in many respects to the red mite. The former flourishes in cool, temperate regions and the latter in warm tropical areas. The life cycle of O. sylviarum, however, differs from that of the other two mites in that all stages, including egg laying, may actually take place on the bird, thus making the parasite more easy to control.
The harvest mites or chiggers ( Trombicula spp.):
These mites are only parasitic in the larval stage, the adults being free-living mites which inhabit old pastures, brush or woodland areas. The larvae attach themselves to the skin and until they become engorged with blood are too minute to be seen with the naked eye. They inject an irritant which digests the skin, thus providing food and producing some capillary bleeding. An inflammatory swelling in the form of a papule or blister occurs around the point of the mite's attachment to the skin. Toxins from the larvae produce intense irritation and even illness or death, especially in small ground-living or ground-nesting birds such as quail. Because of their normal habitat, chiggers should seldom be a problem in well kept aviaries, but during hot weather the matted undergrowth of planted aviaries may attract the mites. They breed during the spring and autumn in temperate regions and at such times a careful watch should be kept in areas where they are known to occur.
Treatment and control:
The ground in the aviary should be treated by spraying with an acaricide to control adult mites. Because of the danger of the acaricide being eaten, birds must be removed before spraying is carried out and some weeks must be allowed to elapse before birds are replaced in the aviary, unless heavy rain washes the substance to the deeper layers of the herbage after spraying. Treatment of individual birds is tedious but it is the only way to clear those which are infested. Dusting or spraying can also be carried out just before the expected chigger season as a preventive measure. When skin reaction to the bites is severe, localized treatment with sulfur ointment, iodine or antibiotic ointments is sometimes helpful. Antihistamines and corticosteroids may also be used when irritation and swellings are extreme.
The Depluming or Body Mange Mite (Knemidocoptes laevis var. g allinae ):
This mite does not occur on most species of cage and aviary birds, but it does occasionally infest pigeons, pheasants and poultry. It invades the feathered areas of the skin, especially around the feather bases, and causes severe irritation. Feathers break off just above the level of the skin, and fall out or become deranged. The skin may show partial or even complete baldness over the back and wings, especially in young birds. Transmission is by prolonged close contact, as for example in the nest, and when birds are overcrowded or huddle together on perches when roosting. The mites are most prevalent during the warm months.
Treatment and control:
This is difficult. Spraying is ineffective, total immersion in a suitable acaricide being necessary to reach the embedded mites. This should be repeated at weekly intervals, but if only a few birds are affected, destruction may be preferable. Protective dipping should be carried out for any birds in contact or on the same premises as those infested. Ointments are messy and unsuitable for treatment. They may help to suffocate the mites but are less penetrating than thin, oily or spirit-based lotions. Malathion, monosulfiram, gamma benzene hexachloride, sulfur in oil, Dettol disinfectant, mineral oil and many others can be used.
Scaly Leg & Face Mites: (Knemidocoptes spp. & Knemidocoptes pilae):
Mites of the genus Knemidocoptes are members of the family Sarcoptidae which includes the mites responsible for scabies in human beings and .mange in domestic animals. In birds they cause the disease known as scaly leg and scaly face. The mites are microscopic, measuring only about one third of a mm. in diameter, poorly mobile, and have short stumpy legs. In most cases the life cycles are not clearly understood.
Knemidocoptes mutans causes scaly leg disease in poultry and K. jamaicensis causes similar lesions in some passerine birds. Closely related species of Knemidocoptes cause similar lesions, the best known being K. pilae the cause of scaly face and scaly leg in budgerigars and also some other psittacines and the canary. The anatomical distinctions between the different species of mites are very small and difficult to detect, calling for an entomologist experienced in the taxonomy of the species. The minute differences between species need not concern us here, because what applies to K. mutans in poultry with regard to clinical signs and treatment applies equally well to K. pilae and other species which infest cage and aviary birds. Various species of birds in Britain, Europe, Australasia, the Americas, the West Indies and elsewhere have been found infested both in the wild and captive states. Some have found a few cases of infestation in old canaries with raised, thickened scales of the legs, but this usually indicates a non-parasitic senile change, perhaps related to poor limb circulation.
The way in which an isolated bird kept indoors can develop mange lesions in middle life is still something of a mystery. Possibilities include a mild, in-apparent, lifelong infestation which flares up for some reason unknown. Seed may be contaminated by wild birds either at its source or in a pet store where birds and seed are kept close together. The most common method of transmission, however, is probably to nestlings from parents during feeding. A heavy infestation at this time may produce defective horn and abnormal growth of the beak to such an extent that a "scissor beak" is formed. This in turn often leads to death from starvation. A typically affected young budgerigar shows a beige colored deposit over one or more of the following areas: the mandibles, the fleshy angle between the mandibles, the cere, the soft skin below the beak, around the eyes and the scaled parts of the legs and feet. Long-standing infestations may spread to the feathered parts beyond these areas. In budgerigars, face lesions are far more common than those on the legs; whereas in passerines the converse appears to be true. In adults the affected areas of skin thicken to a crusty sheet and become knobbly, especially on the movable parts at the angle of the beak and around the eyes. In a few cases, horn-like growths appear from the latter areas in budgerigars and give the birds a most extraordinarily grotesque appearance. In advanced cases the nostrils may become blocked. The dry, chalk-like encrustations are composed of exudate produced by the bird in response to the irritation caused by the mites, plus skin debris thrown up by the mites whilst burrowing in the tissues. Inspection with a hand lens will show the entire area to be a honeycomb of burrows. The horny and underlying tissues, as well as the horn- and skin-producing cells, become permanently damaged.
On the beak, this results in poor quality, crumbly horn being produced which is thicker than normal and fractures or flakes off when the bird de-husks its seed. Where the cere joins the beak, damage to the generative cells causes the diseased horn to grow at different rates and results in the formation of straight, upturned, deviated, wry or scissor-crossed beaks. The sideways pressure exerted by trying to eat with a twisted beak causes severe straining on the supporting bones and other tissues of the jaw. Consequently a permanent deformity of the jaw-bone may also result.
Treatment and control:
Treatment is effective if carried out sufficiently early. Re-infestation is always a possibility, however, because these mites are very common. The usual insecticides and acaricides are rapidly effective, but even painting the lesion with a bland oil such as liquid paraffin or Dettol disinfectant, or mineral oil is useful, at least in early cases. In severe cases, the encrustations should be softened beforehand with such oily preparations before applying an acaricide. Complete disinfestation is best attained by application of the chosen acaricide at intervals of a few days for up to three weeks. Bromocyclen, monosulfiram, benzyl benzoate, or indeed any of the modern acaricides are all effective. An oily or spirit base is preferable for penetration and persistence, but care must be taken not to let the bird peck at the brush during application or to remove and ingest the lotion during preening. All recently acquired and fledgling budgerigars and other parakeets should be closely examined for the characteristic pinhole lesions in the skin over the sites described above. All unusual beaks should be scrutinized under a lens and not assumed to be an inherited defect or due to injury.
Other skin and feather mites:
There are a considerable number of other species which occur on a wide variety of caged and wild birds and which may be encountered from time to time. Some of the species, such as those in the genera Megninia, Rivoltasia, Protalges and Protolichus, live in the plumage and seldom cause trouble unless present in massive numbers. The species Faculifer rostratis is commonly found on pigeons. There are a few mites, for example Syringophilus and Dermoglyphus, which actually inhabit the feather quills and in addition to causing irritation may also produce excessive moulting. Species of Epidermoptes, Microlichus, and Myialges produce mange on most areas of the skin which to the naked eye is indistinguishable from that caused by Knemidocoptes. They do not, however, appear to invade the scaly areas of the legs and feet. The life cycles of most of these mites are either completely unknown or poorly understood.
Treatment and control:
If necessary, the feather mites can be treated in the same way as the red mites. There is no known treatment which is satisfactory for quill mites. The mange mites should be treated in the same way as the Knemidocoptes spp. (scaly leg mite)
Sternostoma tracheacolum and Airsac mites:
This is the only truly pathogenic mite which has been described as occurring in the respiratory system. It has been reported from many parts of the world and occurs in all areas of the respiratory tract. Many species of birds have been found infested including the canary, gouldian finch and budgerigar. Closely related species which are almost identical to S. tracheacolum also occur in a wide range of hosts. Mites such as Cytodites nudus although most frequently confined to the air sacs, have also been reported in various parts of the respiratory tract of the domestic fowl and other birds, but appear to be harmless.
Several other mites have been found inhabiting the upper respiratory passages of pigeons, e.g., Neonyssus and Speleognathus. Very little is known about the life cycles of any of these parasites, but they are not normally pathogenic. Canaries and especially gouldian finches are susceptible to infestations with S. tracheacolum, and may show loss of condition and varying degrees of respiratory distress. Sometimes there is partial or complete loss of voice in the early stages, ruffled plumage and sleepiness. Later characteristic "sucking" or smacking sounds are made, often twice in rapid succession. Coughing, sneezing and gasping for breath result in loss of sleep, as well as loss of condition and eventually death, if no treatment is given. Without a laboratory post-mortem examination, the disease can easily be confused with gapes due to Syngamus worms, the pharyngeal form of pox or aspergillosis.
Although the life cycle is uncertain, it is believed that parent birds may infest nestlings while feeding them with regurgitated food. If therefore, parents are known to be infested, nestlings should be hand-reared if this is possible. Affected birds should always be separated from those which are healthy.
Treatment:
Inhalation of malathion powder has been found to be satisfactory for the treatment of S. tracheacolum. It is relatively non-toxic when compared with other agents. The affected bird is placed in a small sealed box or the cage is covered with a towel, after which the powder is pumped in using an ordinary puffer type dispenser. The bird should be left in the box or cage for five minutes after introducing the powder. The almost inevitable fluttering of the bird will further serve to disperse the powder. The treatment should be repeated at 4-6 weekly intervals. It is advisable to treat only one bird at a time, otherwise injuries may occur whilst fluttering about.
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