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DERMATOMYCOSIS OF ANIMALS

Sh.O. Tokeyev, M. Umitzhanov, B.R. Bizanov

 

Kazakh Scientific Research Veterinary Institute (NIVI) under JSC KazAgroInnovation

 

Dermatomycosis (trichophytosis) is wide-spread infectious diseases among agricultural , carnivorous and domestic animals. Dermatomycosis is diseases that affect skin integuments of animals and human beings. The diseases is caused by a group of imperfect fungi belonging to Trichophyton and Microsporum genera.

In Kazakhstan, the originators of trichophytosis in animals are Trichophyton and Microsporum fungi. The main agents are:

- for camels: Trichophyton sarkisovii;

- for cattle: Tr.verrucosum;

- for sheep and goats: Tr. ver.var autotrophycum;

- for horses: Tr.equinum (Microsporum equinum);

- for cats, dogs and furred animals: Microsporum canis and Tr. mentagrophytes (Microsporum gypseum).

While developing and parasitizing in an animals organism, pathogenic fungi cause severe chronic diseases known as mycotic infections (epizootic lymphangitis, actinomycosis, dermatomycosis etc).

Among fungal zoonoses caused by various fungi species, the most wide spread ones are dermatophytosis (dermatomycosis) of animals and human beings. Dermatophytosis diseases cause a great economic damage to domestic livestock breeding and represent a medical-and-social problem in many countries of the World since diseased animals (cats, dogs, cattle, small cattle, horses, camels and furred animals etc) are often serve as sources of infecting human beings [1, 2, 3, 4, 5, 6, 7].

Thanks to studies of domestic and foreign scientists, by the early 1970-s, there came a clear-cut understanding of the etiologic pathogenesis of the whole group of mycotic diseases caused by fungi, whereby these fungi showed typical parasitic features. These fungi invaded into live tissues of organisms then developed in these tissues and caused nonreversible changes in the said organisms. This group of such diseases is called mycoses (mycotic infections). Lately, the diseases of animals caused by pathogenic fungi have drawn attention of a wide range of specialists in many countries. This attention is due to the damage that is caused by mycoses to the domestic livestock breeding. Mycoses are diseases when one can see the active parasitism of a causative agent, which is a fungal pathogens. As a rule, mycoses are contagious and some of them are dangerous to a human being. Originators of mycoses can cause a pathologic process in animals, whereby such a process can localize mostly in skin, hair-covering (pelage), respiratory apparatus, digestive tracts, urgently tracts, and even in a brain tissue. The majority of mycoses (mycosis infections) are of a chronic type (bald ringworm, epizootic lymphangitis and actinomycosis). A number of mycoses cause immunobiological alterations of an organism, therefore for diagnostics purposes, sensitization tests and serum tests can be performed. Some originators give off a primary luminescence, e.g. originators of microspore. Among mycoses of animals, the most widespread are skin diseases, i.e. dermatophytosis diseases.

In accordance with the data of the foreign specialists, this infection is identified in the majority of the European countries, in the South and North America, Africa, Asia and in the CIS (Former Soviet Union) countries.

Fungi-caused skin diseases are still a source of the infecting of new-born animals of various species. Contacts of human beings with such animals represent a permanent risk of infecting human beings with these zoogenous infections. Originators of dermatomycosis diseases are microspores fungi (micromycete) belonging to Trichophyton and Microspore families.

This group of pathogenic micromycete has been evolutionarily adapted to parasitism on an animals skin regardless of the anatomic structure of involucres (fur, hair, horn tissue). Parasitism of dermatomycosis originators leads to disturbance of physiological properties of skin, skin damage and resultant loss of animal hair/fur. The clinical implications are:

- a low rate of body-weight increase in a young stock,

- degradation/deterioration of the leather quality,

- loss of salable value of the fur,

- loss of a milk productivity among lactating cows.

Presently, dermatomycosis diseases are registered in great cattle and small cattle farms, in camel husbandry farms and in horse-breeding farms as well as in specialized enterprises engaged in breeding valuable fur animals.

According the data from various information sources, the specialists performed mycological examination of the pathologic material of infected animals and animals suspected of being infected. At that, various species of animals were involved. The examination covered various species of animals: from cattle, camels to wild animals and laboratory animals as well as cats and dogs. Out of the pathologic material, trichophytosis and microspore originators were identified and diagnosed.

Dermatomycosis diseases can affect any animal regardless of housing conditions for animals, a quality of animal feed and condition factors. It was found that skin tissue of well-fed animals does not lower a disease rate and a quantity of skin disorders, but on the contrary, the skin tissue of well-fed animals increases a disease rate and a quantity of skin disorders. This fact confirms a selectiveness of pathogenic fungi regarding valuable sources for further development and nutrition of animal dermatomycosis originators.

In fighting against contagious diseases, the most reliable means is application of specific preventive measures in the early ages of animals, i.e. vaccines featuring highly-efficient animal protecting properties. It is necessary to note that animal dermatomycosis originators are represented with pathogenic fungi that are quite resistant to environment conditions, physical and thermal exposures. When coming off diseased animals, skin sloughs, skin crusts and hair contain infection originators and keep their survivability and virulence for years. The specialists found a great vulnerability of young animals to infections. Young animals are under permanent threat of being infected. The cattle that naturally got over trichophytosis develops a strong life-long immunity against this disease Some authors believe that after experimental introduction of dermatomycosis in animals, these animals, after they get over the disease, have a strong life-long immunity against trichophytosis caused by various infectious originators. There is an opinion that during trichophytosis, the tissue immunity is formed, while the humeral immunity is present and seen only at an initial stage of the disease. The experiments with originators of trichophytosis in cattle, horses, camels and furred animals showed that intramuscular injections of trichophytons causes a response from immune-competent systems of the animals. In accordance with the results of their studies, some authors proved that an extent of proliferation of plasmocytes is greater/higher and longer (in time) where immunogenic cultures contain live fungi cells i.e. micro conidia. Allures (micro conidia) serve for conservation of species and are resistant to physical and chemical factors of a respective environment. Besides, allures (micro conidia) are able to form a strong immunity against fungal infections in cattle, horses and furred animals.

This property of allure was registered in 1983 in the National Register of Scientific Discoveries of former the USSR, Document No. 278, titled Capability of Dermatophyte (allure) Cells to Form a Life-Long Immunity (at a saprophytic growth stage) in Mammals as against Parasitic Development of Dermatomycosis Originators.

In order to solve a problem of reliable food-stuff supplies for the Republic of Kazakhstan, to fully meet a market demand for food-stuff and to make the food-stuff available in terms of pricing, to all layers of the society, it is highly important to produce high-quality and competitive food-stuff products on the basis of modern resource-conscious production technologies.

A significant rise in production of agricultural products may be achieved within relatively short time periods by traditional the Republic of Kazakhstan domestic livestock breeding industries, such as horse breeding, camel breeding, cattle breeding and sheep breeding.

To the population, the valuable products are horse meat, beef, camel meat and mutton as well as kumis (horse milk) and shubat (national special preparing camel milk) which have unique medical properties.

Unlike other animal breeding types, drove breeding of horses is highly profitable. The trend is that every year, the population of horses in the Republic of Kazakhstan is on the increase. Presently, according to the data from the Statistical Agency of the Republic of Kazakhstan, the population of horses came to 1 163 500 (as of 2005). The population of camels came to 147 000, the population of cattle came to more than 6 melon, the population of sheep came to 26 melon. A normal development of these industries is impeded by such a contagious disease as trichophytosis.

In spite of similarities in clinical presentations, dermatomycosis diseases are caused by dermathophytes which can be divided into the three following groups:

- trichophytons

- microspore

- Acheron (fauves)

Respectively, three main groups of dermatomycosis diseases are distinguishable in animals:

- trichophytosis

- microspore

- fauves caused by achorions

Similarity of clinical symptoms in dermatomycosis diseases led to a situation when, for a long time period, all this group of diseases was called a single name, which was bald ringworm. However, thorough mycological examinations showed that dermatomycosis disease originators significantly differ in terms of their biologic properties. Therefore, it is quire reasonable that, firstly in medical practice, then in veterinary practice, the term bald ringworm was replaced with such terms as trichophytosis, microspore and fauves.

For the purpose of dermatomycosis disease prevention and therapy, in the Republic of Kazakhstan, the scientists of Kazakh NIVI developed live and inactivated five violent vaccines against dermatomycosis diseases of farm livestock. To fight microspore of carnivorous animals, the scientists developed a bivalent inactivated vaccine.

Presently, for producing biological medicinal products against trichophytosis and microspore, the following fungi strains are used:

- Tr.mentagrophytes F-0316

- Tr. sarkisovii F-0319

- Tr.verrucosum F-0320

- Tr. verrucosum varriantis autotrophycum F-0321

- Tr.equinum F-0322 and

- Microspore canis F-0318

The said fungi strains are deposited in the laboratory for studying genetic material of microorganisms, this laboratory belonging to Kazakh NIVI (KazNIVI) under JSC KazAgroInnovation). Kazakh NIVI lodged an application for an invention and acknowledgements of receipt were obtained.

The fungus strain was identified on the basis of main morphological, cultural and biological properties in accordance with the Qualifier of Fungi Pathogenic, Toxic and Hazardous to Human Beings.

Literature

1.      English M.P., Norris P. Trichophyton mentagropytes var. Erinacei in hedgehog nests // Sabouraudin.-1969.-7.-P.118-121.

2. .. : // .-. .- 1978.- 9.- . 68-75.

3. .. // .- .-1964.-11.-.46-47.

4. .. , // .-1976.- . XXV.-.76-77.

5. ., . .-1996. 46 .

6. .. // .. .- 1985.-2.-.67-68.

7. .. // .: .. .- .-1984.- 252-256.