Caracterização morfológica, morfométrica e molecular de hemogregarinas (Apicomplexa: Adeleina) presentes em répteis de vida livre e cativeiro

Abstract

Hemogregarines (Apicomplexa: Adeleina) are hemoparasites commonly observed in reptiles, being the main genus Haemogregarina and Hepatozoon. Morphological, morphometric and molecular analyzes are essential to distinguish genus and species of these parasites, an initial step to better understand the physiological, biological and behavioral effects of these hemoparasites in reptiles. The present study aimed to determine the positivity and characterize morphometrically, morphometrically and molecularly genus/species of hemogregarinas in free - living and captive reptiles. Samples from reptiles from the states of Minas Gerais, Mato Grosso and Goiás were collected. Blood samples were divided in aliquots to perform blood extensions and as well as PCR. The morphological and morphometric analyzes of blood evolutionary forms were performed in the extensions. PCR was performed with the primers HEMO1/HEMO2 and HEPF300/HEP900. Of 222 samples of reptiles collected, hemogregarines were observed in 45.94% (102), being 46.15% (36/78) from testudines, 70.68% (41/58) from crocodilians and 29.06% (25/86) from snakes. There was a significant difference between positivity and living environment (free life / captivity). The morphological and morphometric analysis, in testudines, showed erythrocytic stages forms of trophozoites, premeronts, micromeronts, macromeronts, two morphologies of macrogametocytes and two morphologies of microgametocytes of Haemogregarina sp. In crocodilians, extraeritrocitic gametocytes and four intraeritrocytic gametocytic stages (in folding, with dispersed nuclear chromatin, cytoplasmic vacuoles and mature were seen, which aided in the identification of Hepatozoon caimani. In snakes, five (MI, M2, M3, M4 and M5) different morphologies and morphometrics of intrateritocytic gametocytes of Hepatozoon sp. were being necessary the molecular technique for identification of species. Due to the scarcity of molecular data on Haemogregarina sp. in testudines, it was not possible to identify species, the few sequences available in GenBank were different from those of the present study. Thus, the morphological, morphometric and molecular information reported in this work infers a possible description of a new species of Haemogregarina, however further studies will be carried out to confirm this suspicion. In crocodilians, there aren´t published molecular data of Hepatozoon caimani, being the present study the first one. However, in snakes through molecular analysis it was possible to identify species of Hepatozoon, such as Hepatozoon musa parasitizing Crotalus durissus of free living and captivity environment and Hepatozoon cevapii parasiting Boa constrictor and Bothrops spp. From this study, we conclude the need to use the morphological, morphometric and molecular diagnostics to identify genus and species of hemogregarines in free-living and captivity reptiles, a initial step to know better the biological, physiological and behavioral effects of these parasites in these animals.