Interactions of spodoptera littoralis haemocytes following injection with the entomopathogenic fungi: Beauveria Bassiana and Nomuraea Rileyi

This study compared the cellular interactions of Spodopteralittoralis haemocytes with two virulence-different entomopathogenic fungi: Beauveriabassiana and Nomuraearileyi. Using light and transmission microscopy, five types of haemocytes namely, prohaemocytes [PRs], plasmatocytes [PLs], granulocytes [GRs], spherule cells [SPs] and oenocytoids [OEs] were identified in the 6[th] instar larvae. PRs and PLs were found in the haemopoietic tissue.Intra-haemocoelic injection of blastospores induced ultrastructural alterations in the cytoplasm and nucleiof circulating haemocytes of treated larvae. Different responses were observed in the populations of haemocyte types following injection with the tested fungi. The most important changes were the decrease of the numbers of GRs aiccompanied with increase inSPs at 12-48h following injection with B. bassiana, whereas,a decrease of PLs with a commitment increase inSPs and OEs were observed at most time intervals after injection with N. rileyi. Both fungi provoked a decrease of the total number of haemocytes at 48h followed by an increase at 72h post-injection. In vivo assay showed that the GRs and PLs actively phagocytised fungal blastospores. There was a time-dependent decrease and increase in the phagocytosis activity after injection of B. bassiana and N. Rileyi, respectively .In B. bassiana-injected insects, the numbers nodules increased significantly at 6-48h in comparison with the controls post-injection. In N. rileyi-injected insects, nodules increased significantly only at 72h post-injection.No cellular encapsulation was observed in any of the examined insects

Preliminary field trials with culicinomyces clavosporus against some Egyptian mosquitoes in selected habitats

Culicinomyces clavosporus was isolated from diseased larvae of Culex pipiens collected from brackish water habitat. Pure cultures of the fungus were grown on nutrient agar media. Field studies were undertaken on a variety of habitats of mosquitos. Evaluations included artificial pool studies and field trials. The fungus was applied once to three different natural breeding habitats of mosquitos at a dose rate of 1010 conidia/m2. C. Clavosporus addition to unpolluted rice field that had high densities of Cx. Antennatus and low densities of Anopheles tenebrosus Doenitz and Cx. Perexiguus resulted in 100% control of the larvae five days post treatment. The addition of the fungus to brackish water habitat supporting large brood of Ae. Caspius and few numbers of Culiseta longiareolata [Macquart], Cx. pusillus and Cx. pipiens was equally effective

Some ultrastructrual studies on the excretory bladder of the adult cynodiplostomum azimi [trematoda: digenea] in infected rats

Transmission electron microscope was used to reveal the reserve bladder system of the adult Cynodiplostomum azimi in experimentally infected rats. It was shown that this system consisted of a number of lacunae. The lacunar lining appeared as syncytial epithelium containing many nuclei, mitochondria, dense secretory bodies, Golgi complex and bundles of smooth muscles. The outer surface of the excretory epithelium was highly folded and lamellated. These lamellae were continuous with the excretory epithelium. Small lipid droplets were observed within the excretory epithelium, while larger ones were associated with the lamellae. The large lipid droplets were released in the lacunal lumen after the rupture of the lamellae surrounding them

Scanning electron microscopy of the small intestine of rats experimentally infected with cynodiplostomum azimi

Scanning electron micrographs of the proximal intestine of rats infected with C. azimi showed mild villous changes and excessive mucus secretion as early as the first day after infection. On the second day, the regular leak-like pattern of the villi was not seen, the epithelial lining of the mucosa was damaged with large amounts of mucus. Goblet cell openings appeared either empty or filled with secretions. The mucosal damage persisted for three months. Four months after infection, villi regained part of their normal pattern. Their epithelial lining although less damaged, appeared delicate. Villi away from the worm were less affected. Pathological changes at different intervals of infection were discussed in relation to the surface structure of the parasite

Ultrastructural study of the tegument of cotugnia polyacantha and killigrewia streptopelia inhabiting the dove streptopelia senegalensis aegyptiaca

The ultrastructure of the teguments of the cyclophyllidean cestodes Cotugnia polyacantha and Killigrewia streptopelia naturally infecting the dove Streptopelia senegalensis aegyptiaca was studied using transmission electron microscopy. The two cestodes inhibit two distinct sites in the small intestine of the same bird. Observations revealed basic similarity between the two cestodes, though, marked differences between the tegument structure of the two species were reported regarding the structure and dimension of microtriches, types and distribution of vesicles among the regions of the tegumental / perikaryal complex, structure of subtegumental connective tissue and subtegumental muscle layer. The significance of these observations was discussed in possible relation to the different physiochemical environments known to occur where each cestode resides