Charlie's Pond (North Carolina) harbors a diverse community of trematodes that infect the planorbid snail Helisoma anceps. Research at the Pond began in 1984 and serves as a foundation on which to investigate long-term changes in trematode communities. In 2002, 2005, and 2006 average size and fecundity of H. anceps were calculated each month, and seasonal trends analyzed with randomization test...

Toxoplasma gondii has a very wide intermediate host range and is thought to be able to infect all warm blooded animals. The parasite causes a spectrum of different diseases and clinical symptoms within the intermediate hosts and following infection most animals develop adaptive humoral and cell-mediated immune responses. The development of protective immunity to T. gondii following natural infe...

Alternative transmission strategies are common in many parasitic organisms, often representing discrete phenotypes adopted in response to external cues. The facultative truncation of the normal 3-host life-cycle to a 2-host cycle in many trematodes provides an example: some individuals mature precociously, via progenesis, in their intermediate host and produce eggs without the need to reach a d...

Thirty-six freshwater fish from Bung Borapet, a large reservoir, were examined for helminths in July 2005. The prevalence of infection was 19.44 (7/36) and the intensity was 4.67 (168/36) per fish. Seven fish were infected with 4 species of helminths: 1 trematode, Clinostomum philippinensis (metacercariae); 1 cestode, Senga chiangmaiensis; 1 acanthocephalan, Pallisentis sp and 1 nematode, Camal...

A serotonergic pathway is apparently involved in parasite-host interactions. Previous studies conducted in our laboratory showed increased rates in oxygen consumption and alterations in body posture in the crab Hemigrapsus crenulatus parasitized by the acanthocephalan, Profilicollis antarcticus. Such changes may be related to the functions described for biogenic amines in crustaceans. During th...

Freshwater snails of the genus Biomphalaria are important intermediate snail hosts for the widespread transmission of schistosomiasis in humans. This chronic and debilitating disease remains one of the most intractable public health concerns in 74 developing countries, infecting more than 200 million people. Prevalence of schistosomiasis is difficult to estimate, but according to the World Heal...

The low stringency-polymerase chain reaction (LS-PCR) with a pair of specific primers for the amplification of the 18S rRNA gene was evaluated as a means of differentiating between the two Schistosoma mansoni intermediate host species in Brazil: Biomphalaria glabrata and B. tenagophila. Individual snails obtained from different states of Brazil were used and the amplification patterns obtained ...

For conspecific parasites sharing the same host, kin recognition can be advantageous when the fitness of one individual depends on what another does; yet, evidence of kin recognition among parasites remains limited. Some trematodes, like Coitocaecum parvum, have plastic life cycles including two alternative life-history strategies. The parasite can wait for its intermediate host to be eaten by ...

Single-miracidium infections of Lymnaea cubensis (Pfeiffer) from Guadeloupe with the giant liver fluke Fascioloides magna (Bassi, 1875) (Digenea) were carried out during five successive snail generations to determine if this lymnaeid might sustain complete larval development of the parasite. Controls were constituted by a French population of Galba truncatula (Miller) (a single generation) infe...