Generalist parasites exploit multiple host species at the population level, but the individual parasite's strategy may be either itself a generalist or a specialist pattern of host species use. Here, we studied the relationship between host availability and host use in the individual parasitism patterns of the Shiny Cowbird Molothrus bonariensis, a generalist avian obligate brood parasite that ...

BACKGROUND: Bovine leukemia virus (BLV) is an oncogenic deltaretrovirus causing a persistent lifelong infection of B lymphocytes. In addition to the domestic cattle, the virus can also infect water buffaloes. OBJECTIVES: Recent investigations have demonstrated the increasing prevalence of BLV infection among cattle population in Iran. Large popul...

Marine microbial interactions involving eukaryotes and their parasites play an important role in shaping the structure of phytoplankton communities. These interactions may alter population densities of the main host, which in turn may have consequences for the other concurrent species. The effect generalist parasitoids exert on a community is strongly dependent on the degree of host specificity...

aphid parasitoids (braconidae: aphidiinae) in several localities of kerman province, southeastern iran were studied between 2007 and 2008 and 20 species belonging to eight genera were identified. parasitoids were reared from 25 field-collected aphid species occurring on 31 host plant species. in the present study, 83 parasitoid-aphid-plant associations, their aphid hosts, and the respective hos...

Parasite life-history characteristics, the environment, and host defenses determine variation in parasite population parameters across space and time. Parasite abundance and distribution have received little attention despite their pervasive effects on host populations and community dynamics. We used analyses of variance to estimate the variability of intensity, prevalence, and abundance of 4 s...

Information about similarities and differences in the demographic history of host and parasite populations is potentially useful for making inferences about a variety of evolutionary processes. However, it is difficult to observe the historical demographic properties of natural populations directly. Here, the extent of demographic similarity in a host and its parasite was examined indirectly by...

A comparative analysis of parasite species richness was performed across 53 species of fish from the floodplain of the upper Paraná River, Brazil. Values of catch per unit effort, CPUE (number of individuals of a given fish species captured per 1000 m(2) of net during 24 h) were used as a rough measure of population density for each fish species in order to test its influence on endoparasite sp...

(1) Three categories of biological processes are shown to have a destabilizing influence on the dynamical behaviour of model host-parasite associations: parasite induced reduction in host reproductive potential, parasite reproduction within a host which directly increases parasite population size and time delays in parasite reproduction and transmission. (2) The importance of parasitic species ...

Bee-population declines are linked to nutritional shortages caused by land-use intensification, which reduces diversity and abundance of host-plant species. Bees require nectar and pollen floral resources that provide necessary carbohydrates, proteins, lipids, and micronutrients for survival, reproduction, and resilience to stress. However, nectar and pollen nutritional quality varies widely am...