TICKS PARASITIZING THE SPUR-THIGHED TORTOISE (TESTUDO GRAECA) POPULATION OF TUNISIA

Tick infestation in spur-thighed tortoise population: a pilot study for unraveling epidemiological patterns and demographic consequences

Ectoparasites, such as ticks, modulate host population dynamics by impacting demographic traits. They transmit infectious agents among their hosts, posing a critical threat to animal and public health. This study aimed to characterize and analyze the Hyalomma aegyptium infestation on one of its main hosts, the spur-thighed tortoise, its effects on demographic traits, and to determine the diversity of infectious agents present in both ticks and tortoises in the Maamora forest (northwestern Morocco). Our results show that 100% of the tortoises were parasitized by adult ticks in spring, an infestation intensity of 4 ticks/tortoise (5.1 and 3.6 ticks/tortoise in males and females, respectively; 4.2 and 3.3 ticks/tortoise in gravid and non-gravid females, respectively) and an abundance ranging from 1 to 12. Although without significant differences, male tortoises had higher tick abundances than females. The interaction of tortoise sex and body condition was significantly related to tick abundance, male body condition decreased with higher tick abundance in contrast to females. Nevertheless, the interaction of body condition and reproductive stage of females was not significantly related to tick abundance. Gravid females were significantly associated with tick abundance, showing a slightly higher infestation than non-gravid females. Molecular analysis of pooled tick samples revealed the presence of Ehrlichia ewingii, Candidatus Midichloria mitochondrii, and Rickettsia africae, with a minimum infection rate of 0.61 to 1.84%. However, blood sample analysis of the tortoises was infectious agent-free, pinpointing a lack of significant health problems. Given the possible effect on the transmission of zoonotic diseases by spur-thighed tortoises associated with their frequent collection as pets, it should be surveyed to control possible human health problems. In conservation terms, as a long-lived species, the role of tick infestation in demographic traits might be included in the management and conservation programs of spur-thighed tortoises.

Detection and molecular identification of Anaplasma phagocytophilum and Babesia spp. infections in Hyalomma aegyptium ticks in Tunisia

Tortoises of the genus Testudo are the main hosts of Hyalomma aegyptium ticks. This species serves as a vector of several zoonotic pathogens. Therefore, the present study aimed to investigate the presence of four pathogens associated with H. aegyptium ticks obtained from tortoises from Tunisia. Conventional, multiplex and nested PCRs were used for Aanaplasma phagocytophilum, Ehrlichia canis, Coxiella burnetii and Babesia spp. screening. The molecular analyses revealed the presence of A. phagocytophilum and Babesia spp. None of the ticks, were infected by E. canis or C. burnetii species. Co-infection was detected in four ticks. As a conclusion, this is the first detection of A. phagocytophilum and Babesia spp. in H. aegyptium ticks collected from tortoises, in Tunisia. Thus, considering these results, the spur-thighed tortoise constitute a potential host of H. aegyptium which plays an important role in the transmission of pathogenic agents affecting both human and animals. In term of public health, a strict control and surveillance should be carried to reduce the circulation of such pathogens between different hosts.