The species richness of freshwater environments is disproportionately high compared with that of the oceans, given their respective sizes. If diversification rates are higher in freshwaters because they are isolated and heterogeneous, this should apply to parasites as well. Using 14 large datasets comprising 677 species of freshwater and marine fish, the hypothesis that freshwater parasites exp...

Declines in moose (Alces alces) populations have occurred repeatedly during the past century on the southern fringe of moose range in central and eastern North America, generally in the same geo-climatic regions. These prolonged declines, occurring over a number of years, are associated with higher than usual numbers of co-habiting white-tailed deer (Odocoileus virginianus). Numerous proximate ...

Abstract A key benefit of sociality is a reduction in predation risk. Cohesive group behaviour and rapid collective decision making are essential for reducing risk groups. Parasite infection might reduce an individuals’ grouping behaviours thereby change the as whole. To investigate relationship between parasite behaviours, we studied groups three-spined sticklebacks, Gasterosteus aculeatus , v...

because of endemic parasitological infectious diseases in iran and contaminated vegetables, as one of the most important ways of contamination, carried out a parasitical study on 263 vegetable samples from 44 farms in the suburbs of tehran city, and also 166 vegetables samples from 20 green grocery markets in the same city. from 263 samples of farms 147 cases (65%) of contamination were recorde...

To explore the mechanisms of antigen-specific immune unresponsiveness seen in microfilaremic patients with bancroftian filariasis, T and B cell precursor frequency analysis was performed using PBMC from individuals with either asymptomatic microfilaremia (MF, n = 7) or chronic lymphatic obstruction (CP, n = 20). Highly purified CD3+ cells were partially reconstituted with adherent cells and the...

The current study was conducted in Misan Governorate to detect the parasite Sarcocystis spp. by both conventional and molecular methods identify species of this genus goats as intermediate hosts for multiple parasite. Regarding traditional study, rates infection with macroscopic type were low recorded 2% esophageal samples only goats. sizes cysts ranged between 1-10 mm length 2-6 width. Infecti...

We investigate the initial behaviour of a deterministic model of parasitic infection, appropriate to transmission between homogeneously mixing hosts, where the amount of infection which is transferred from one host to another at a single contact depends on the number of parasites in the infecting host. In this model, R0 can be de ned to be the lifetime expected number of o spring of an adult pa...

Title of Document: THE INFLUENCE OF PARASITE-DERIVED CHEMOKINES IN LEISHMANIASIS Sean Martin Conrad, Doctor of Philosophy, 2006 Directed By: Professor David M. Mosser Department of Cell Biology and Molecular Genetics Transgenic chemokine-secreting parasites were generated and used to actively recruit immune cells into Leishmania lesions. It was hypothesized that the chemokine induced cell migra...

Host-mediated responses and parasite density-dependent processes can have a major influence on the growth and fecundity of parasitic nematodes. However, host characteristics and parasite intensity consistently change during the course of an infection and these could affect worm length and number of eggs in a non-constant way. We used a free-living population of rabbits naturally infected with T...

Large numbers of parasites are found in various organs of anuran amphibians, with parasite intensities thought to modulate the host's Darwinian fitness traits. Interaction between the anuran hosts and their multiple parasites should modulate the host's phenotypic characteristic, such as those associated with high energetic demand (such as calling effort and locomotor performance), energy balanc...