Trypanosoma equiperdum

Trypanosoma equiperdum is a type of single-celled parasites of the genus Trypanosoma, which occurs as pathogens dourine, a venereal disease in horses. The parasite is transmitted in contrast to all other pathogenic trypanosomes not by insects, but almost exclusively when mating.

Discovery and description

The first description of trypanosomes in the blood of patients suffering from dourine horse dates from the year 1896 by working in Algiers on military hospital doctor J. Rouget. Of Franz Theodor Doflein the pathogen Trypanosoma equiperdum was called; the epithet equiperdum is composed of the Latin words equus ( horse) and perdere ( spoil ) together.

The protozoa have a single flagellum which extends on the cell surface with an undulating membrane to the front end of the cell and there is a free-running scourge. The cells also have a small kinetoplast, an accumulation of deoxyribonucleic acid inside a large mitochondrion; this may be absent in some isolates. The parasite occurs only in a trypomastigotes cell shape. Microscopically the parasite Trypanosoma brucei or Trypanosoma not be distinguished evansi.

Trypanosoma equiperdum is classified in the subgenus Trypanozoon. All representatives of this subgenus, which in addition Trypanosoma equiperdum and Trypanosoma evansi and Trypanosoma brucei are, are not only microscopic, but also very similar for molecular properties. Trypanosoma equiperdum differs from Trypanosoma brucei practically only by partial absence of kDNA maxi Circles, occurring in many copies in kinetoplast mitochondrial DNA. Deletions in mitochondrial DNA cause that Trypanosoma equiperdum unable to reproduce in tsetse flies, as encoded by the mitochondrial DNA genes for oxidative energy metabolism, which is required of trypanosomes in tsetse flies for propagation, are essential. In mammals, trypanosomes is limited to glycolysis for energy.

Detailed molecular studies came to the conclusion that Trypanosoma equiperdum is not monophyletic, but a set of multiple spontaneous mutations caused by Trypanosoma brucei group; it was concluded that a classification as a separate species was not warranted. It has been proposed to classify the subtype of parasite Trypanosoma brucei brucei, Trypanosoma equiperdum labeled.

Distribution and host animals

Originally, the parasite was common in horses worldwide. Today he is in Central Europe, North America and Australia as eliminated. At the World Organisation for Animal Health diseases from Botswana, Ethiopia, Kyrgyzstan, Namibia, Pakistan, Russia and South Africa were still being reported in recent years. The only natural hosts are horses, mules and donkeys. Dogs, rabbits and rodents can be infected experimentally.

Life cycle

Trypanosoma equiperdum has the simplest life cycle of all trypanosomes. An increase takes place only in mammals, a change of form, as with other trypanosomes does not occur. The transmission from horse to horse during copulation. But there is also evidence of a transfer from the mare to the foal. After mating, the parasites multiply in the tissues of the urinary and genital system, from there but temporarily in the bloodstream. The number of parasites in the blood is low in comparison to other trypanosomes, which makes the detection of the parasite greatly.