Endogenous development of Hemolivia mauritanica (Apicomplexa: Adeleina: Haemogregarinidae) in the marginated tortoise Testudo marginata (Reptilia: Testudinidae): evidence from experimental infection

Abstract

Abstract. Six young tortoises Testudo marginata Schoepff, 1792 were experimentally infected with Hemolivia mauritanica (Sergent et Sergent, 1904). The prepatent period ranged from 6 to 8 weeks. Young, smaller, club-like forms (6-9 × 3-6 µm) of gametocytes appeared in the peripheral blood first, whereas mature, elongated, cylindrical forms (9-12 × 5-7 µm) were detected after 1-2 weeks and predominated during later patency. Three of the infected tortoises were euthanized and dissected to study the endogenous stages. Meronts occurred in the cells of the reticulo-endothelial system and in the erythrocytes; these were observed mostly in parenchymatous organs. Mature forms measured 14.2 × 9.3 µm and contained 7-12 merozoites. Cysts with two (exceptionally one) cystozoites were also found predominantly in parenchymatous organs and measured 14.8 × 7.9 µm. Pathological changes attributable to Hemolivia were mild and limited to liver and kidneys. The role of individual developmental stages of haemogregarines is discussed with respect to evolution of heteroxenous life cycle and long-term persistence of parasites in their intermediate hosts.

Hemolivia species infecting Central American wood turtles (Rhinoclemmys pulcherrima manni) and problems with differential diagnosis within the genus Hemolivia

“…A blood smear captures the situation of a single moment, so it is usually dominated by mature gamonts. Obtaining information on the sequence of individual developmental stages in real time would require either experimental infection under laboratory conditions ( e.g ., for Hemolivia : [ 12 , 18 , 19 , 23 , 25 ]), or very frequent, repeated sampling of the same individuals in the field ( e.g ., using radiotelemetry). We named the detected blood stages by approximation with these Hemolivia species that have described life cycles.…”

“…Blood smears were air-dried, fixed in absolute methanol for 10 min, stained with Giemsa as described in Široký et al . [ 23 ], and then microscopically examined with an Olympus BX53 microscope using the 100× magnification lens equipped with immersion oil. Photomicrographs were captured using an Olympus DP 73 digital camera.…”

“…Furthermore, parameters LW (length × width) and L/W (length/width ratio) were calculated. The intensity of parasitemia was estimated for each infected turtle as the percentage of infected red blood cells found in approximately 10 4 cells [ 23 ].…”