Schistosomiasis is an important parasitic disease that infects humans. Among the main species of schistosomes infecting humans is Schistosoma mansoni and S. haematobium. Snails of various genera, such as Biomphalaria alexandrina and Bulinus truncates, act as intermediate hosts and play a major role in the transmission of schistosomes. Transmission from human to snail is under the influence of t...

Fasciolosis is a parasitic helminthes disease caused by Fasciola gigantica. The different larval stage (sporocyst, redia and cercaria) are found in intermediate host snail Lymnaea acuminata. In the present study it has been tried to kill the F. gigantica larvae in vitro/ in vivo condition by the use of ferulic acid there is no mortality of snails. Mortality of larvae in in vivo and in vitro con...

An unnamed microcercous cercaria (Digenea: Monorchiidae), a parasite of Amiantis purpurata (Lamarck, 1818) (Bivalvia: Veneridae) and its corresponding metacercaria from the province of Buenos Aires and the Patagonian coast of the Southwest Atlantic Ocean, are described. The cercaria described in this paper differs from the three other monorchiid microcercous cercariae, i.e., Lasiotocus minutus ...

Schistosomiasis is a debilitating disease that affects over 240 million people worldwide and is considered the most important neglected tropical disease following malaria. Free-swimming freshwater cercariae, one of the six morphologically distinct schistosome life stages, infect humans by directly penetrating through the skin. Cercariae identify and seek the host by sensing chemicals released f...

Twenty-eight Dorper wethers, allocated according to age into 4 groups of 7 animals each, and 1 group of 7 Merino wethers, were compared for susceptibility to Schistosoma mattheei infestation. The group mean ages of the Dorper sheep varied from 5-61 months and their live mass from 25-66 kg, while the Merinos were 8 months old and had a mean mass of 19 kg. Despite the marked differences in the ag...

Brachylaima cribbi is a recently described species of terrestrial trematode that infects mammals and birds with helicid land snails as its first and second intermediate hosts. The adult worm is 2.5-6.0 mm long by 0.5-0.8 mm wide being a long slender cylindrical worm with oral and ventral suckers in the anterior quarter and genital pore in the posterior quarter. Scanning electron microscopy show...

Sanguinicolids, or fish blood flukes, infect the vascular system of both marine and freshwater fishes, and some act as serious pathogens of hosts in aquaculture. Blood flukes typically possess a relatively benign relationship with wild fishes; however, cultured hosts near appropriate intermediate hosts (i.e., snail, bivalve, or polychaete) may accumulate heavy infections of the worms and their ...

Protective immunity against schistosomiasis induced by vaccination of mice with irradiated cercaria can be passively transferred to uninfected mice with sera or IgG. Antigens that are uniquely or more strongly recognized by such protective sera compared with sera from infected unprotected mice have been identified previously. Two genes, SmIrV1 and SmIrV5, were selected from an adult worm cDNA l...

The biogenic amine serotonin (5-hydroxytryptamine: 5HT) is a widely distributed neuroactive substance of vertebrates and invertebrates. Among parasitic flatworms, in particularly the bloodfluke, Schistosoma mansoni, 5HT is an important modulator of neuromuscular function and metabolism. Previous work has shown that schistosomes take up 5HT from host blood via a carrier mediated mechanism. This ...

Previous investigations of sensory systems in opecoelid cercariae have focused on chaetotaxy and ultrastructure of sensory receptors. They revealed chaetotaxic patterns within family, genus, and species as well as different receptors. Chaetotaxic and ultrastructural observations have rarely been combined. We investigated the ultrastructure of cercarial sensory receptors in conjunction with chae...