Studies on three species of the genus Cystocephalus schneider, 1886 [apicomplexa: eugregarinida: stylocephaliae] with special reference to host specificity and distribution of members of family stylocephalidae in Egypt

Three species belonging to genus Cystocephalus, Schneider 1886 were found parasitizing three coleoptra hosts. Out of 105 Blaps polychresta, only one male was infected with C. algerianus and females were parasites free. Ten percent of examined Pimelia angulata [n = 30] were infected with the same parasite. Among are one male [5.56%] and 2 females [16.67%]. Out of 126 of Trachyderma hispida 6 [4.76%] were parasitized by C. gabei. Only 3 males [5.1%] and 3 females [4.48%] were harbouring this parasite. Cystocephalus albrechti were found infecting 78 [61.9%] out of 126 of T. hispida. Forty six males [77.93%] and 32 females [47.76%] were infected. Males of the three tenebrionid hosts were more susceptible to infection rather than females. B. polychresta was considered a new host for C. algerianus in Egypt. Also, C. albrechti might be considered as specific host for T. hispida. Mid and hind gut appeared blackened in case of massive infection [>240 parasites per host] of parasitized males of C. albrechtj. The host specificity and the first biogeographical map fort distribution of stylocephalids and cystocephalids are provided here

Biological studies on the snail intermediate hosts of schistosomiasis with a special emphasis on using larval echinostomes as biocontrol agent against larval schistosomes and snails

The present investigation dealt with the infectivity of the two snail intermediate hosts of schistosomiasis, Biomphalaria alexandrina and Bulinus truncatus collected from nine drains in Sharqia Governorate, Egypt. The rate of infection among the snails was generally low in many drains. Regarding B. alexandrina, the rate of infection ranged 4-16% and in B. Truncatus ranged 4-8%. Infection with larval echinostomes was dominant over larval schistosomes in the two snail vectors. The distribution of larval schistosomes was restricted to the hepatopancreas of the two snail vectors, while larval echinostomes were distributed in head foot, kidney, hemocoelic cavity and hepatopancreas,. etc. The predation of larval schistosomes by larval echinostomes and the severe histopathological effects induced by larval echinostomes strongly enhanced using them as biocontrol agent. The physicochemical parameters and pollution condition in the drains seemed to have no effect on the process of snails infectivity. The results of the study showed that larval echinostomes can resist the polluting conditions in the drain. The two snail vectors exhibit very minimal or rare host response against larval echinostomes. The toxicants and pollutants in the drain may act as stressor that makes the snails much more susceptible to infection by larval trematodes

Pairing of schistosoma mansoni males in infected Syrian hamsters

Pairing of male schistosomes in the liver of infected hamsters was recorded with Egyptian S. mansoni strain. The homospecific male pairs never carried each other in the gynecophoric duct, but they are closed in either central or hepatic veins. Other perfused males and females en copula showed normal mating behavior. The paired males were more or less in the same size. The random sexed miracidia used resulted in obtaining 1: 2.1 female/male ratio. It is concluded that the random increase of male schistosomes may create the male pairing behavior. Also, the migration of female against the blood stream to the mesenteric plexus of the host and the failure of male to catch them may lead to this homosexual pairing. The black hemozoin- like substance seen in mature females was also observed in the pairing males and this probably reflects the effect of scarcity or migration of females to the mesenteric plexus

Effect of behavioural stress on susceptibility of Syrian hamsters to schistosoma mansoni infection: effect on number and fertility of worm burden

The effect of pairing on the susceptibility of male Syrian hamsters to Schistosoma mansoni infection in comparison with their isolated counterparts has been studied. Pairing resulted in significant differences between paired and isolated hamsters in the measurements of eggs, miracidia, number of adult worms recovered and mean testicular number of males. Paired hamsters seemed to be immunologically suppressed and such a suppression resulted in increasing the fertility and number of worms recovered. The width of the male Schistosomes recovered from the paired hamsters was two folds and the length was four folds greater than those recovered from isolated ones. It was concluded that the stressed host reflected effects on the number and fertility of the schistosome worms burden, hence the severity of the disease and its complications

histopathological effect of metacercariae of the genus brachylaima on the land snail, monacha obstructa

The histopathological changes in the kidney of the land snail Monacha obstructa and the histochemistry of the body wall of the parasite were studied. The histological pictures of the infected kidney showed extensive degree of degeneration in the renal tissue with multiple necrotic foci. Due to the mechanical and feeding effects of the parasite, the renal lamellae were disintegrated. Also, suckers increased the renal damage. In some levels of the kidney, the renal tissue was completely disappeared except the connective tissue of kidney capsule. Also, it was observed that there was a clear space between the parasites and renal tissue probably as a trial of evasion from the Host's reaction. The histochemical study on the metacercarial body wall revealed that it is consisting of 3 layers arranged as outer, middle and inner layers. Staining with periodic acid Schiff proved that the body wall is rich in mucopolysaccharide content. The idea that this parasite can be used as a biocontrol agent was also discussed

Larval occurrence of hydatigera taeniaeformis Batsh [1786] [cestoda: taeniidae] in the liver of wild rodents in Egypt

Hydatigera taeniaeformis Batsch [1786] was found in the liver of six species of Egyptian wild rodents. The total incidence of this larval stage was found to be 20.0% among cestode infection. It was found in 40.9% Rattus norvegicus, 33.3% Gerbillus gerbillus, 26.8% Rattus rattus, 25.0% Mus musculus, 16.6% Acomys cahirinus and 7.2% Arvicanthis niloticus. The cysts of Hydatigera taeniaeformis was always occupying the marginal surfaces of both right and left lobes and sometimes there was a double cyst contained two strobilae. The rostellar hooks used for identification. The strobilae obtained were in different stages of development. The rostellar hook system was complete and so the suckers, but the segment showed no maturation. Morphological characters and role of rodents as intermediate host for such cestode are discussed

Studies on the nematode parasites from Egyptian rodents 1- spirurid nematodes

Three spirurid nematode species have been collected from Egyptian rodents in Giza province. Streptopharagus kuntzi was collected from stomach and small intestine of Rattus ratus, R. norvegicus, Arvicanthis niloticus and Gerbillus gerbillus. Protospirura muris and P. marsupialis have also been collected from A. niloticus, R. rattus and R. norvegicus but P. marsupialis was collected only from the stomach while P. muris collected from stomach and small intestine. P. marsupialis was firstly recorded in Egypt during this work and no males of this species were collected. Females of S. kuntzi and P. muris showed marked dominance over males. Streptopharagus sudanensis and S. kuntzi are placed in synonomy