Hallazgo de «Trypanosoma» en «Pseudoseisura lophote» (Cachalote Castaño)

MERA Y SIERRA, ROBERTO ; QUERO, MARTÍN ; NEIRA, GISELA ; GODOY, DAYANA ; CABALLERO, SOFÍA ; PUEBLA, BELÉN ; BAZTÁN, MARÍA DULCE ; MARINOZZI, ANABELLA ; ZARCO, AGUSTÍN

Jornada; III Jornadas Internacionales de Investigación, Ciencia y Universidad y las XII Jornadas de Investigación UMaza; 2020

Hallazgo de ?Trypanosoma? en ?Pseudoseisura lophote? (Cachalote Castaño)Finding of ?Trypanosoma? in ?Pseudoseisura lophote? (Brown Cachalote)Avian trypanosomes are vector-borne hemoparasites of birds and numerous (approximately 100) species of the Trypanosoma genus have been described worldwide. Their geographical range is vast, from hot tropical to very cold climates. The descriptions of species have been based both on morphological and molecular grounds, and frequently the assumption is made that each species of trypanosome is exclusive of its bird host. Thus quite probably we are far from knowing the real situation. It has been suggested that unlike what happens with mammals infected by trypanosomes, in birds these would not be a frequent cause of disease, yet, studies have demonstrated that they can cause serious disease with profound pathological changes which can be of concern when addressing conservation issues. The intermediate hosts described are haematophagous insects belonging to different families of Diptera and dermanyssid mites. To the best of our knowledge, there are no published reports referring to bird trypanosomes in Argentina. The objective of this work is to report the presence of Trypanosoma sp. in Pseudoseisura lophotes (brown Cachalote). P. lophotes is amply distributed in South America and classified in the Red List as of Least Concern, yet its population trend appears to be decreasing. During September 2017 a specimen of P. lophotes was captured in a mist net in the Telteca Natural Reserve in Mendoza province, Argentina. A blood sample was taken from vena ulnaris cutanea, a blood smear was preformed, fixed with methanol and stained with Giemsa and examined at 1000x for the presence of hemoparasites. Pictures of the parasite were taken with a digital camera on an optic microscope at 1000X magnification. A calibrated micrometer was used as a measure reference to analyze the image of the parasite with Image Analysis Software Fiji®. The following measures were taken, BW: body width; FF: distance from the flagellum free end to the anterior end of the body; NA: distance from the anterior end of the body to the center of the nucleus; KN: distance from the center of the nucleus to the center of the kinetoplast; PK: distance from the center of the kinetoplast to the posterior end of the body; bK: kinetoplast breadth; lK: kinetoplast length; bN: nucleus breadth; lN: nucleus length.All procedures involving animals were approved by the Internal Animal Care and Use Committee (CICUALID). Two trypanosomes of similar morphology were found, yet in only one of them the all the structures were preserved enough to allow all the measurements. The results obtained from measuring the trypanosome were the following: BW: 2.13µm; FF: 9.86 µm; NA: 6.58 µm; KN: 8.01 µm; PK: 1.34 µm; bK: 0.73 µm; lK: 0.95 µm; bN: 1.62 µm; lN: 1.97 µm. It had a slender form, small size and terminal kinetoplast. This would classify them, according to Kučera, as a type A trypanosome, the one less frequently encountered. The low parasite burden coincides with reports for avian trypanosomes were even though prevalence may be high, intensity of parasitemia is usually low upon examination of the blood smear. It is interesting that Triatoma platensis and Triatoma infestans, vectors of Trypanosoma cruzi, have been found in nests of P. lophote. It would be important to investigate if they could be the vectors of the trypanosome found in the present work. The present work is a starting point for the characterization of this trypanosome.