[Show abstract][Hide abstract] ABSTRACT: This study assessed the anisakid nematode distribution pattern in the fish collected from coasts of Mediterranean Sea, Egypt, during the period September 2010-April 2011. Two hundred thirty out of 300 (76.7%) Dicentrarchus labrax (European seabass) marine fishes belonging to family Moronidae were dissected and found to be infected with larva three nematodes. The larvae had been studied by light and scanning electron microscopy. The present work represents the first record of the presence of the parasite in this fish in the Mediterranean Sea. The concentrations of some heavy metals (Pb, Zn, Fe, Cd, Cu, Mn, Ni) in parasites as well as in tissues of fish were measured. The presented results showed that the nematode parasites are able to accumulate heavy metals in their tissues and in some cases that they are able to accumulate large amounts of heavy metals in a higher amount than host tissues. This demonstrated their sustainability as bioindicators of environmental pollution by removing heavy metals and help in the survival of fish.
No preview · Article · Aug 2011 · Parasitology Research
[Show abstract][Hide abstract] ABSTRACT: The life cycle of Hepatozoon hemprichi n. sp. is described; the vertebrate host is Scincus hemprichii and it is vectored by Hyalomma impeltatum. Erythrocytic stages of 18 ± 1.8 × 4 ± 0.8 µm developed in the hemocoel of ticks to sporozoites within 16-18 days. Schizogony occurred in the liver parenchyma and the endothelial cells of blood capillaries in lung and spleen. Mature schizonts measuring 27 ± 3.11 × 20.13 ± 3.0 µm produced 28 merozoites (on average). The merozoites were 13 ± 1.21 × 1.21 ± 0.72 µm with nuclei 5 ± 0.65 × 2.1 ± 0.51 µm. Syzygy and differentiation of gamonts took place in tick's hemocoel up to the third day post-infection (PI). The microgamont (16 ± 0.31 × 18 ± 0.42 µm) produced 4, uniflagellated microgametes at 4-5 days PI. The microgamete measured 15.2 ± 0.31 µm while the flagellum was always at least 26 µm. The macrogamete was very large in size (31 ± 3.11 µm) with a central nucleus. After fertilization, (5-6 days PI) zygotes developed into oocysts (55 ± 3.41 × 52 ± 4.11 µm) in which repeated mitotic divisions with centripetal invaginations occurred; each contained 18 banana-shaped sporozoites, 13.61 ± 0.8 × 1.2 ± 0.31 µm in size. Experimental transmission was successfully carried out by oral administration or by intra-peritoneal inoculation of the infective stages (sporozoites) to uninfected skinks and led to the appearance of blood stages after 5 wk and 4 wk, respectively.
No preview · Article · Jun 2011 · Journal of Parasitology
[Show abstract][Hide abstract] ABSTRACT: In the present investigation, macroscopic sarcocysts of Sarcocystis acanthocolubri were observed in muscles of 42 (4.3%) out of 975 Acanthodactylus sp. lizards collected from different geographical areas in Egypt. The infection rate was 6.4% in Acanthodactylus boskianus, 2.1% in Acanthodactylus sculentus, and 5% in Acanthodactylus paradalis. The highest infection rate was recorded in the lizards captured from Baltem (10% in A. boskianus and 8% in A. paradalis). The infection rate was usually higher in females (7.4%) than in males (3.8%). Moreover, the highest infection rate was recorded in summer (7.53%), autumn (3.57%), and spring (3.11%), and the lowest was recorded in winter (0.91%). Also, old animals had higher infection rates (10.8%) than young ones (0-2.7%). Macrocysts measured 0.95 × 10.12 mm. Both macroscopic and microscopic sarcocysts were enclosed only by a primary cyst wall, which had many finger-like, stalkless, and non-branched protrusions giving it a striated appearance. The primary cyst wall measured 3.9 μm. A dark granulated ground substance was found directly underneath the protrusions and is extended interiorly dividing the cyst cavity into many compartments containing the parasites (metrocytes and merozoites). Metrocytes were found directly under the ground substance and usually multiply asexually by endodyogeny producing two merozoites from each metrocyte. Both metrocytes and merozoites had the apical complex structures characteristic to the genus Sarcocystis. Transmission experiments with three snake species indicated that the snake Spalerosophis diadema is the proper final host belonging to the family Colubridae. The prepatent period was 16 days, while the patent period was 35 days. The results obtained from the present investigation revealed that this is a new species which was named Sarcocystis acanthocolubri.
No preview · Article · Jun 2011 · Parasitology Research
[Show abstract][Hide abstract] ABSTRACT: Cysts of Sarcocystis capracanis obtained from infected goats were examined to clarify the effect of the parasite on the host. Muscle tissues from fresh oesophagus, tongue, diaphragm and skeletal muscles of 680 goats were slaughtered in the main abattoir of Cairo, Egypt and they were examined microscopically for Sarcocystis infection for the first time in Egypt. 540 out of 680 (79.4%) of examined goats were found to be infected with Sarcocystis sp. The infection was recorded firstly by light microscopy as spindle shaped cysts embedded in the muscle tissues. The validity of this species as S. capracanis was confirmed by means of ultrastructural characteristics of the primary cyst wall which revealed the presence of thick-radially striated wall with finger like projections, underlined by a thick layer of ground substance enclosing the developing metrocytes and merozoites that usually contain nearly all the structures of the apical complex and fill the interior cavity of the cyst. The cyst cavity is divided by many septa extending from the ground substance and producing large number of chambers. An experimental infection using the highly infected muscles was carried out to determine the final host, which is dog. Smears of intestinal epithelium were taken to examine the endogenous stages (gamogony and sporogony) by means of light microscopy. These stages were mainly observed as to infect the lamina propria of the posterior third of the small intestine. Gamogony and zygote formation (fertilization) occurred 2-8 days post infection, while sporulation took place within the final host 13-15 days and sporocysts were passed within faeces of the infected puppies at that time. The prepatent period of S. capracanis was 12-15 days, while the patent period was extended to 37 days. In goats, infection with S. capracanis led to the loss of weight, anaemia, abortion and even death in cases of heavy infection. While bleeding, watery faeces filled with mucous on 5th and 8th day p.i. as well as intestinal lesions are the pathogenic effects occurred in puppies after experimental infection.
Full-text · Article · May 2011 · Veterinary Parasitology
[Show abstract][Hide abstract] ABSTRACT: Benedenia (Capsalidae) is a genus of important oral and cutaneous fluke parasite of aquarium, cultured and marine fish. In the present study, the morphological and morphometric characterization of Benedenia sciaenae,
a monogenean parasite infecting the gills of the brown-spotted grouper fish Epinephelus chlorostigma were
described by means of light microscopy as a first description from Epinephelus chlorostigma. 215 out of 290
(74.1%) fish samples were found to be infected with this ectoparasitic capsalid causing pathogenic and epizootic
events. The adult worm is flattened, elongated with an anterior adhesive organ enclosing two anterolateral adhesive
structures, each one possesses three lobes which aids for adhesive secretions while the enlarged posterior end
enclosing haptor. The adult worm measured about 0.52 -0.67 (mean 0.59 ±0.03) mm in total length and 0.33 – 0.49
(mean 0.38 ±0.02) mm in width. Haptor width measured 0.25-0.29 (mean 0.26 ± 0.02) mm; its hard parts consist of
two pairs of hamuli and the accessory sclerites. The anterior hamulus measured 0.027-0.034 (mean 0.31±0.002) mm
long while the posterior one measured 0.030-0.040 (mean 0.036±0.002) mm and each of the accessory pieces
measured 0.032-0.044 (mean 0.040±0.002) mm long. Results showed that the general morphology of the present
Benedenia sp. resembles that of B. sciaenae described previously in Turkeys from Argyrosomus regius fish host
with the dimensions of body more or less similar. Also, there were significant correlations (P≤0.05) between fish
length, weight and parasite abundance per fish. Number of monogeneans was increased with host size and age to
fish of intermediate length and weight, and then it decreased probably because changes in size of gill filaments
affect their attachment capability, enhancing the possibility of being detached by respiratory currents.
No preview · Article · Jan 2011 · Life Science Journal
[Show abstract][Hide abstract] ABSTRACT: Out of 2,343 examined sheep throughout the whole year, 271 were found to be infected with tapeworms (11.5%). The highest infection rate (22.1%) was recorded in autumn, while the lowest (6%) occurred in summer. Six species of cestodes were identified according to their prevalence: Moniezia expansa (74%), Moniezia denticulata (8.5%), Moniezia benedeni (4.8%), Moniezia trigonophora (2.7%), and Thysaniezia giardi (2.7%), T. giardi was recorded in Egypt for the first time. M. expansa was found throughout the year with two peaks in January (92.3%) and June (88.5%). SEM examination revealed that M. expansa scolex has four triangular suckers guarded by an X-shaped fibrous band that makes them open permanently. Also, there is a Y-shaped apical part at the scolex center which may be an embryonically non-developed rostellum. The whole worm body surface is covered with unidirectional microtriches. TEM showed that the tegument is underlaid by a thick fibrous interstitial layer below which an outer circular and an inner longitudinal muscular layer are arranged. Beneath these structures the subtegumental cells are found which have spherical electron-dense inclusions and various other cell organelles. Moreover, M. expansa has interproglottidal glands which contain secretory vesicles and secretions. For biological control of this parasite, different concentrations of crude plant extract of Artemisia cina were used in vitro and in vivo. In vitro, the results indicated that the plant extract is efficacious at all concentrations tested. Electron microscopic examination showed that many structures of the treated worms were affected. The most affected sites were the scolex and the microtriches of the outer tegumental surface. In vivo, treatment of heavily infected animals showed an antihelminthic effect, since the complete absence of eggs was recorded 9 days after treatment when fecal investigations were done.
Full-text · Article · Jan 2011 · Parasitology Research