Heba M. Abdel-Haleem

Coccidiosis of domestic rabbit (Oryctolagus cuniculus) in Egypt: light microscopic study.

In the present study, the incidence and prevalence of coccidian infection among domestic rabbits in Egypt were investigated. Severe overall prevalence reaching 70% (70/100) was recorded. Eight species of Eimeria were detected. Mixed infection with three different species occurred most frequently. Eimeria intestinalis and Eimeria coecicola were generally the most predominant species. The complete life cycle of E. intestinalis was investigated. This study is the first to report coccidia in domestic rabbits in Egypt. Six species of Eimeria were reported for the first time.

Endogenous stages of Choleoeimeria baltrocki (Daszak et Ball, 1991) n. comb. infecting the gall bladder of gold skink, Eumeces schneiderii Daudin, 1802 from Egypt

Examination of 98 gold skink, Eumeces schneiderii Daudin, 1802 from Alexandria and Marsa-matroh Governorates, Egypt revealed oocysts of Choleoeimeria baltrocki (Daszak et Ball, 1991) n. comb. in the gall bladder and faeces. The prevalence of the infection was 40.8%. Sporulated oocysts were found in the faeces and the gall bladder contents. Sporulated oocysts were tetrasporocystic, cylindrical, reaching a mean of 38.7 (36–42) × 19.9 (17–25) μm with bilayered smooth and colourless wall. The dizoic sporocysts were subspherical and measuring 10.8 (9.5–13) × 9.3 (8–10.5) μm with a large globular sporocyst residuum. Sporocyst wall was bilayered joined by meridional suture. Sporozoites were crescent-shaped, blunt at one end and slightly tapered at the other. Endogenous stages (meronts, gamonts, gametes and young oocysts) were confined to the gall bladder epithelium and the infected cells were hypertrophied. Based on the morphological features of the exogenous stages and endogenous development of the present parasite, its generic affiliation was revised and placed into the genus Choleoeimeria.

Anticoccidial activities of Chitosan on Eimeria papillata-infected mice

Eimeria spp. multiply within the intestinal tract causing severe inflammatory responses. Chitosan (CS), meanwhile, has been shown to exhibit anti-inflammatory activities in different experimental models. Here, we investigated the effect of CS on the outcome of inflammation caused by Eimeria papillata in the mouse intestine. Investigations were undertaken into the oocyst output in feces and developmental stages and goblet cells in intestinal tissue. Assays for lipid peroxidation, nitric oxide (NO), and myeloperoxidase (MPO) were also performed. T cells in intestinal tissue were counted using immunohistochemistry while total IgA in serum or intestinal wash was assayed using ELISA. In addition, mRNA expression of tumor necrosis factor alpha (TNF-α), transforming growth factor β (TGF-β), interleukin (IL)-10, and IL-4 were detected using real-time PCR. The data indicated a reduction in both oocyst output and in the number of parasite developmental stages following CS treatment, while the goblet cell hypoplasia in infected mice was also inhibited. CS decreased lipid peroxidation, NO, and MPO but did not alter the T cell count or IgA levels in comparison to the infected group. The expression of TNF-α and TGF-β decreased but IL-10 and IL-4 increased after CS treatment in comparison to the non-treated infected group. In conclusion, CS showed anti-inflammatory and protective effects against E. papillata infection.

A New Sarcocystis Species (Apicomplexa: Sarcocystidae) from the Rock Gecko Bunopus tuberculatus in Saudi Arabia

Abstract: Sarcocystis bunopusi n. sp. from the muscle fibres of the rock gecko (Bunopus tuberculatus) in Saudi Arabia is described. Sarcocysts were found in skeletal muscles of the tail and fore and hind limbs in 3 of 30 geckos. Sarcocysts were microscopic, 42–45 µm long and 22–25 µm wide. Using light microscopy, the cyst wall was thin and smooth. Ultrastructurally, the primary cyst wall consisted of a thin parasitophorous vacuolar membrane with osmiophilic 100 nm × 50 nm knob-like papillae, and no perpendicular protrusions. Septae were indistinct. Bradyzoites were 5–7 × 1.5–2.0 µm in size. This is the first description of a Sarcocystis species from this gecko.

Electron Microscopic Study of the Developmental Stages of Eimeria Intestinalis Cheissin , 1948 in Domestic Rabbit Oryctolagus Cuniculus with Reference to Endodyogeny

The endogenous stages in Eimeria intestinalis were studied in experimentally infected coccidia-free rabbits by transmission electron microscopy. Four asexual generations were ob- served.Two types of merozoites were reported. Binucleated merozoites possess all the characteristics of apical complex indicating asexual reproduction by endodyogeny. While the second type, the mononuclear merozoites have one central nucleus. Gamonts were developed mainly from the third generation merozoites where the mature gamonts were recorded together with the fourth generation schizonts. Macro- and microgametogenesis were clearly observed. Development of microgametes and its fine structural characteristics were detected. Mature macrogametes with central large nucleus and the appearance of two types of wall forming body (I, II) were observed. Many reserve food materials including amylopectin granules and lipids droplets were very characteristic. Control experimentally infected rabbits shed unsporulated oocysts on the day eight p.i.

Rhabdias bufonis (Rhabdiasidae) from the lung of the African common toad, Amietophrynus regularis (Bufonidae) in Egypt. New data on the basis of light and scanning electron microscopic study

Background and Aims Rhabdias sp. (Rhabdiasidae) is a nematode parasite of family Rhabdiasidae infecting the lung of amphibians. The present study provides new morphological details for Rhabdias bufonis isolated from the lungs of the African common toad, Amietophrynus regularis based on observations of light and scanning electron microscopy (SEM). Methods Forty specimens were collected from its natural habitat: the damp, moist fields and gardens at Giza governorate, Egypt. Worms were isolated from the lungs, fixed and then preserved. They were examined using light and SEM with further line drawings. Results Fourteen specimens (35%) were found to harbor Rhabdias with an intensity of three to five worms per host. Bodies of the gravid females were elongated, slender, measured 3.22–9.86 (5.64 ± 0.03) long and 0.09–0.48 (0.23 ± 0.02) wide at mid-length. Buccal capsule was with cylindrical lumen and sclerotized walls. Ovaries were almost straight. The uteri were located anterior and posterior to the vulva. Uterus were filled with a large number of eggs (17–42). Eggs were oval in shape and some of them were with fully developed larvae inside. The tail was comparatively short, gradually tapered. SEM showed that worms possessed an oval anterior end with a simple, slit like oral opening. The lipless edges of the mouth opening were bordered with tiny cuticular elevations, radiated outwards. Two pairs of submedian cephalic papillae were observed around the oral opening as well as two amphids. Conclusion The current study presents new morphological details for R. bufonis isolated from the African common toad. Also, the morphology of the slit-like mouth opening, the two pairs of cephalic papillae, two amphids and the three pairs of cuticular elevations supporting the area around mouth opening were investigated.

Molecular characterisation of Hepatozoon aegypti Bashtar, Boulos & Mehlhorn, 1984 parasitising the blood of Spalerosophis diadema (Serpentes: Colubridae)

Hepatozoon aegypti Bashtar, Boulos & Mehlhorn, 1984 was first described from the blood of the diadem snake (Spalerosophis diadema) in Egypt. During an investigation of the diversity of reptilian haemogregarines in Saudi Arabia, seven diadem snakes (100% of the sample) were found to be highly parasitised by H. aegypti, with an average parasitaemia of 37% per 500 counted erythrocytes. A complete characterisation of this species with morphometrics and 18S rDNA sequence data is therefore presented here. The infection was found to be restricted to the erythrocytes with, frequently, single and, sometimes, double infections. Mature gamonts were sausage-shaped with round posterior and anterior extremities and measured 14 (13–17) × 3.5 (3–5) μm. The infected erythrocytes were hypertrophied with a faintly stained cytoplasm and longitudinally stretched nuclei. The merogonic stages occurred only in the endothelial cells of the snakes’ lungs, and no stages were found in other organs. Mature meronts were round in shape, measured 18 (17–21) μm in diameter and were estimated to produce between 9 and 15 merozoites. Phylogenetic analysis based on the partial 18S small subunit ribosomal DNA sequences indicates that Hepatozoon aegypti cluster within a mixed clade of Hepatozoon species parasitising snakes, geckos and rodents from various geographic areas. Our results might reinforce the theory of prey-predator transmission in respect to the relationships of snake-host Hepatozoon species.

Immunoprotective responses against murine sarcocystosis by β - Irradiated sporocysts

This study aimed to induce protective immunity against infection with Sarcocystis muris in experimental mice using β-irradiated sporocysts. Mice were vaccinated with 50 sporocysts of S. muris which were exposed to 1.84 μSv β-irradiation for 2, 4 and 8 h. After challenge infection, different samples were taken for evaluation. Serum and intestinal wash were assayed for IFN-γ and IgA, respectively. Mesenteric lymph nodes (MLNs) and spleen were investigated for CD4+ and CD8+ T cells using immunohistochemistry. For liver, the morphological changes in parasitic stages and the count of infiltrated CD8+ T, NK1.1+ and FasL+ cells were also investigated. Real time (RT) - PCR was used for detection of liver MHC I, CD1d, IFN-γ, perforin and FasL as well as the parasite 18S ribosomal(r) RNA in liver and muscle tissues. Alterations of liver parasitic stages as well as a decrease in the infection with the parasite in both of liver and muscle tissues were dependent on radiation exposure time. An investigation for the mechanism of immunoprotection showed an increase in liver NK1.1+ & FasL+ cells, serum IFN-γ and intestinal IgA, while CD4+ and CD8+ T showed a remarkable increase in MLNs and spleen. FasL expression increased in the liver dependently on radiation exposure time, while perforin, MHC I and CD1d were not. β-irradiated sporocysts with 1.84 μSv for 8 h s could induce the highest protection against infection with Sarcocystis. This could be largely relied on the increased infiltration of NK cells and associated higher expression of FasL in the liver.

Ultrastructural and molecular characteristics of Kudoa crenimugilis n. sp. infecting intestinal smooth muscle of fringelip mullet Crenimugil crenilabis in the Red Sea

This study describes infection of intestinal smooth muscle in fringelip mullets Crenimugil crenilabis with Kudoa crenimugilis n. sp. Of 30 individuals sampled from the Red Sea off Saudi Arabia, 6 (20%) were infected. Ovoid plasmodia (279-412 × 157-295 µm) in the smooth muscle of the intestine were packed with only mature myxospores with 4 valves. Specifically, light and transmission electron microscopy revealed quadrate myxospores with 4 equal, rounded, spore valves uniting at thin delicate suture lines. The mature myxospores were 8 (7-9) µm long, 5.2 (5-6) µm thick and 7.8 (7-8) µm wide. The 4 polar capsules were equal-sized, elliptical to ovoid, and measured 5 (4-5) µm long and 2 (1.5-3) µm wide, possessing 2 filament coils. The sporoplasm was uninucleated and composed of a primary cell enveloping a secondary cell. The parasite had a significant histopathological impact since the developing plasmodia replaced normal muscle tissue and was associated with the myolysis of local muscle fibres and the inflammatory infiltration of lymphocytes and macrophages. The partial sequences of the 18S and 28S rDNA showed that K. crenimugilis n. sp. has the highest level of nucleotide similarity with K. ciliatae (98.46 and 94.11%, respectively) and K. cookii (97.51 and 92.11%, respectively), both of which have previously been reported from the intestines of their host fish. Phylogenetic analysis revealed that K. crenimugilis consistently clustered with these other 2 intestinal Kudoa species in a well-supported subclade, confirming the evaluative association between Kudoa species infecting the same organs.

Redescription and new locality record of Choleoeimeria turcicus from the gallbladder of Hemidactylus turcicus in Egypt, with notes on its endogenous development

Upton et al. J Protozool 35:24–25, 1988 originally described Eimeria turcicus from the gallbladder of the Mediterranean gecko, Hemidactylus turcicus, in the USA. Shortly after establishing the genus Choleoeimeria, Paperna and Landsberg S Afr J Zool 24:345–355, 1989 transferred E. turcicus to this genus, renaming it as Choleoeimeria turcicus. This paper reports the findings of a survey of coccidian parasites of lizards in Egypt, during which tetrasporocystic oocysts were reported from the gallbladder of H. turcicus. Based on the oocysts’ morphological and morphometric characteristics and the same host, it can be deduced for the first time that the present species is conspecific with E. turcicus. In the present study, the gallbladder was the sole site for the endogenous development and no endogenous stages were noticed in the intestine. The endogenous stages induce hypertrophy and displacement of the infected cells from the original biliary epithelium to form a prolonged and branching outgrowth. We therefore followed Paperna and Landsberg S Afr J Zool 24:345–355, 1989 and considered the biliary coccidium recorded in this study to be a member of the genus Choleoeimeria. This represents a new locality record for C. turcicus, which was previously known in the USA and Israel.