Treatment of Air~sac Mites

Abstract

DEDICATION

Throughout the world there are individuals actively practicing their private hobby of aviculture without adequate scientific data. This lack of information is nowhere more apparent than in the field of avian medicine.

The commercial development of avian medicine is seen by the industry to have a low profit potential and thus not deserving of their capital investment. It is, therefore, left to the private sector to fill this gap by developing their own data, while reserving its use for the private aviculturist. Thus, those who have the most to gain may do so, while the industry who saw fit not to make the investment, will not make the profit.

It is with this in mind that this paper is being written and dedicated only to those who are interested in and practicing their private hobby of aviculture.

INTRODUCTION

In 1964 I began to notice many of my Canaries and Lady Gouldians had

asthma. The obvious remedy was Lo breed this OUL of them. But while gathering information on how to do so, air-sac mites came into the picture.

During 1965 and 1966 all my Lady Gouldians and my best canaries died of these mites. Handicapped without a medical background and realizing the odd-, against success, I S\\ ore a personal vendetta to rid myself of these "Bugs".

The following chapters describe, in brief, much of what was learned during the next ten years. It is the result of nine basic studies plus an additional 14 substudies and experiments. An attempt is made Lo put forth useful information taken from a file over two reams thick, gathered at an expense in excess of$5,000, after thousands of man hours of work and thousands of miles traveled.

DESCRIPTION STERNOSTOMA TRACHt'ACOLUM

These mites appear almost clear to dark red, depending upon how recently they last fed. As true blood suckers their appearance darkens as they gorge with the

blood or their host I'hcir size is such as to be the smallest speck visible to the naked eye, and then only when gorged and on a light background.

More spcci [ical ly males have been studied at a length of 400 microns and a width of200 microns with all eight (8) legs directed anteriorly or anterolaterally. Females were studied at a length of 590 microns and a width of265 microns with a larger full abdomen and a radial arrangement of the legs. Both had lateral leg extension of 59 microns to 61 microns.

Very little is known about their life cycle. However, many of this family (rhinonyssid) are viviparous and go through larva, nymph and adult stages all within the same host. Their spread is associated with direct bill contact during the mating season and while feeding the young. It is also possible, although very improbable, these mites could be passed in the drinking water and even more improbable on common feeding areas.

SYMPTOMS

The infested birds will cough while trying to rid themselves of the irritation. They

will frequently wipe their bills and hold it open while breathing. The noise of air moving through the mite obstructed trachea can be heard as a wet asthmatic sound when the beak or chest is placed near the ear. This is due to the mucus formed around the mite. In more advanced cases, in cool, damp weather, or when the bird becomes more active, these symptoms can be heard several feet away.

Infested individuals often become very lethargic, puffed, and demonstrate obvious signs of labored breathing. On occasion a moderate or severe case will, when excited, bend its head back while doing back flips on the cage floor. This is due to a strong oxygen demand and an attempt to clear the airways for sufficient air passage. Panic then sets in, which further increases oxygen demand along with an increased, heart beat. Death will soon result unless the bird quickly becomes calm and relaxed.

Resistance varies widely among individuals. Some die in the nest while others live for years. Although the mites keep the birds in a weakened condition, the death rate is low. The open sores left by the feeding mites are the entry points of secondary infections. These infections of bronchopneumonia, bronchietasis, streptoccus and other pathogenic organisms along with pulmonary emphysema are the main cause of death.

SPECIES INFESTED

The most common and troublesome infestations are found in canaries and Lady Goldian finches. Many other birds throughout the world have been shown to have St. tracheacolum.

Domrow, of Australia, has found no less than four wild species of Australian birds, in the Queensland district alone, to carry St. tracheacolum. Other researchers have found them in sparrow, bunting, tanagers, warblers, wagtails, starlings, blackbirds, orioles, meadowlarks, budgerigars and some small finches. Generally, these latter findings are believed to be of little significance, except in isolated cases of crowded aviaries and then only in the very small finches, i.e. Cordon Bleu, Red ear, Orange check wax bills, and Parrot finches.

During autopsy and with the use of an ordinary dissecting microscope these mites can most easily be found in the trachea. Here some experimenters have found over 100 mites. Other findings can be made on the heart and liver due to the air-sacs adjacent to these organs. Upon close examination mites may be found in all air ways and air-sacs including the hollow bone structure. The common name "air-sac mite" is

truly accurate.

In canaries and Gouldians the problem is acute and very widespread. Several knowledgeable veterinarians have told me they almost never see a flock without an infestation of St. tracheacolum, and further, they doubt if many exist. The few exceptions could be credited to an improperly sampled flock and/ or improperly examined individuals.

At this point it must be remembered that we are speaking of just one mite and its hosts. There are thousands of species of mites which live inside their host. Each requires a specific environment ranging from other insects to reptiles, mammals and birds.

CURES - SYMPTOMATIC OR REAL

In the past 10 years many "cures" have been advanced. After proper investigation most have fallen short of a true cure. Some of the more popular treatments are worth discussion.

Malathion has been used in two basic forms. The most common is to place the bird in an environment of 5% to 10% dust for a few minutes. Thus, the powder is inhaled.

Inhaling Malathion does alleviate the audible symptoms emanating from the trachea. However, recent research has shown that very little gets into the blood stream. Thus, the mites residing deeper in the air-sacs are little affected. The addition of carriers is too dangerous to the bird for practical use. Even if Malathion were to be administered orally, it is doubtful that effective blood levels could be reached.

In one case, fogged malathion seems to have removed the mites. However, this is true after repeated and continued use in very high concentrations. It is generally believed this treatment is too dangerous for general use by most aviculturists.

Pyrethrum powders and aerosol sprays have been widely used in the same manner as malathion, but in very low percentages. This chemical is designed to breakdown the insects protective wax covering. It seems to have a level of effectiveness on the symptoms as it works in the trachea. However, here again the blood level is very low. The mites in the deep air-sacs are not affected and the bird remains infested.

Various "Pest Strips" have been used both in open aviaries and in small enclosed cages. These are made of a solid material which slowly releases insecticides to be inhaled by the host. While the pest strips are effective on most insects, they are very ineffective on internal parasitic mites due to the low blood level.

Most recently Sulfaquinoxaline (S.Q.) showed strong possibilities of cure. It was

administered in the water at .0050Jo for 90 days. Some experimenters used considerably stronger solution, up to .20Jo. The best we can say is that this metabolic inhibitor does get into the blood stream. However, aviculturists have reported no improvement in canaries and Gouldians.

In summary, it seems that these treatments are effective only on the general clinical symptoms. They do little toward long term control, much less cure, as their effects are local rather than through the blood stream. At this point there was still the need to find a substance with high lethal effects on insects and relatively low toxicity in birds and then to devise a method of administering this substance to effect the death of the St. tracheocolum but not of its host.