Haemogregarine (Apicomplexa: Adeleorina) infection in Vanderhaege's toad-headed turtle, Mesoclemmys vanderhaegei (Chelidae), from a Brazilian Neotropical savanna region

Hemoparasite Analysis and Hematological Parameters of Four Freshwater Turtle Species (Testudines: Podocnemididae) from the Brazilian Amazon

METHODS

Sampling was performed at three sites in the Tapajós River mouth, Pará State, Brazil, and an aliquot of blood was collected from each turtle by post-occipital dorsal vein puncture. The aliquots were used for the determination of hematological parameters and for the study of hemoparasites in the blood samples.

RESULTS

A total of 37 turtles were sampled: 21 Podocnemis expansa, three P. sextuberculata, nine P. unifilis, and four P. erythrocephala. Parasitological analyses showed inclusions in erythrocytes compatible with Haemogregarina sp., representing an overall prevalence of parasitized animals of 64.8% with an average of 94,789 parasites/ml of blood. In this study, the evolutionary forms of Haemogregarina spp. from trophozoites, pre-meronts, meronts, and mature and immature gamonts were observed in three species of freshwater turtle species, and one morphotype of the parasite with high similarity to Haemogregarina podocnemis has been observed.

CONCLUSION

Despite recent research on freshwater turtles, this study provides new information on the intensity of blood parasite infection and hematological parameters of free-living animals, highlighting the need for studies on infected and uninfected animals from the same population.

Detection of Hemopathogens in Chelonoidis carbonaria: Microscopic, Molecular, Hematological, and Clinical Biochemistry Aspects

Background: The growing contact between men and wild animals, caused by the increase in the population in urban centers and the destruction of the habitat of these animals, has been leading to a greater circulation of pathogens between humans and wildlife. Chelonoidis carbonaria, a tortoise found throughout South America, is one of the animals most rescued from animal trafficking and illegal breeding. Considering this situation, this study aimed to verify the occurrence of hemoparasites in C. carbonaria. Materials and Methods: Blood samples from 73 C. carbonaria were collected from animals located in (1) a rural commercial breeding unit, (2) an urban zoo, and (3) a center of rescued animal screening. Genomic DNA was extracted from these animals and used in PCRs to detect specific genomic fragments of haemogregarines (i.e., Hepatozoon and Hemolivia), and members of the Anaplasmataceae Family (i.e., Ehrlichia sp. and Anaplasma sp.). Blood samples were screened for hemopathogens by direct microscopy and were used for hematological assays, and serum samples were analyzed to determine the concentration of serum components. Results: It was found that 34.2% of the tortoises presented Sauroplasma sp. in their blood samples; these animals showed clinical biochemistry changes that indicate altered liver function. Two zoo animals were positive for Ehrlichia sp. in PCR, and also presented clinical biochemistry and hematological changes. Conclusion: The present project is pioneer in the detection of Ehrlichia sp. in C. carbonaria, and was able to identify changes in clinical biochemistry that can be a result of the infection by hemopathogens in this species.

Hemogregarine Diversity Infecting Brazilian Turtles with a Description of Six New Species of Haemogregarina (Apicomplexa: Adeleorina: Haemogregarinidae)

(1) Background: Hemoparasites of the genus Haemogregarina (Haemogregarinidae) are commonly reported in freshwater turtles. However, in Brazil, only three species have currently been characterised using molecular methods. This study aimed to bring new insights on the diversity of species of Haemogregarina infecting Brazilian freshwater turtles from Mato Grosso and Goiás states using molecular and morphological tools. (2) Methods: In total, 2 mL of blood was collected, with between two to five blood smears prepared, fixed with absolute methanol, and stained with a 10% Giemsa solution. Blood was stored at −20 °C for molecular analysis targeting the 18S rRNA gene. Fragments of the organs (liver, spleen, heart, and kidney) were separated and stained with hematoxylin-eosin. (3) Results: A total of 40 turtles were screened and hemogregarines were observed in 34 (85%) individuals (3 Podocnemis expansa and 31 Podocnemis unifilis). Haemogregarina embaubali and six new species of Haemogregarina were observed and formally described as follows: H. unifila n. sp., H. rubra n. sp., H. goianensis n. sp., H. araguaiensis n. sp., H. tigrina n. sp., and H. brasiliana n. sp. (4) Conclusions: This study contributes to the diversity and knowledge of Brazilian fresh-water turtle blood parasites, using integrative approaches for diagnosing and characterizing hemoparasites, with the identification of six undescribed species.

Haemogregarines and Criteria for Identification

Simple Summary

Taxonomic classification of haemogregarines belonging to Apicomplexa can become difficult when the information about the life cycle stages is not available. Using a self-reporting, we record different haemogregarine species infecting various animal categories and exploring the most systematic features for each life cycle stage. The keystone in the classification of any species of haemogregarines is related to the sporogonic cycle more than other stages of schizogony and gamogony. Molecular approaches are excellent tools that enabled the identification of apicomplexan parasites by clarifying their evolutionary relationships.

Abstract

Apicomplexa is a phylum that includes all parasitic protozoa sharing unique ultrastructural features. Haemogregarines are sophisticated apicomplexan blood parasites with an obligatory heteroxenous life cycle and haplohomophasic alternation of generations. Haemogregarines are common blood parasites of fish, amphibians, lizards, snakes, turtles, tortoises, crocodilians, birds, and mammals. Haemogregarine ultrastructure has been so far examined only for stages from the vertebrate host. PCR-based assays and the sequencing of the 18S rRNA gene are helpful methods to further characterize this parasite group. The proper classification for the haemogregarine complex is available with the criteria of generic and unique diagnosis of these parasites.