Search results for "Diplostomum"
showing 8 items of 38 documents
Data from: Interactions among bacterial strains and fluke genotypes shape virulence of co-infection
2015
Most studies of virulence of infection focus on pairwise host-parasite interactions. However, hosts are almost universally co-infected by several parasite strains and/or genotypes of the same or different species. While theory predicts that co infection favours more virulent parasite genotypes through intensified competition for host resources, knowledge of effects of genotype by genotype (G×G) interactions between unrelated parasite species on virulence of co infection is limited. Here we tested such relationship by challenging rainbow trout with replicated bacterial strains and fluke genotypes both singly and in all possible pairwise combinations. We found that virulence (host mortality) …
Data from: Reciprocal interaction matrix reveals complex genetic and dose-dependent specificity among coinfecting parasites
2012
Understanding genetic specificity in factors determining the outcome of host-parasite interactions is especially important as it contributes to parasite epidemiology, virulence, and maintenance of genetic variation. Such specificity, however, is still generally poorly understood. We examined genetic specificity in interactions among coinfecting parasites. In natural populations, individual hosts are often simultaneously infected by multiple parasite species and genotypes that interact. Such interactions could maintain genetic variation in parasite populations if they are genetically specific so that the relative fitness of parasite genotypes varies across host individuals depending on (1) t…
Data from: Genotypic and phenotypic variation in transmission traits of a complex life cycle parasite
2013
Characterizing genetic variation in parasite transmission traits and its contribution to parasite vigor is essential for understanding the evolution of parasite life-history traits. We measured genetic variation in output, activity, survival, and infection success of clonal transmission stages (cercaria larvae) of a complex life cycle parasite (Diplostomum pseudospathaceum). We further tested if variation in host nutritional stage had an effect on these traits by keeping hosts on limited or ad libitum diet. The traits we measured were highly variable among parasite genotypes indicating significant genetic variation in these life-history traits. Traits were also phenotypically variable, for …
Data from: Parasite infection in a central sensory organ of fish does not affect host personality
2016
Among the ecological factors acting on the evolution and expression of animal personalities and behavioral syndromes, parasitism has received comparatively little attention. However, infection and host behavior are often strongly intertwined, because host behavior can predict the risk of infection and can also be changed by an infection. We conducted a controlled experimental infection study to explore the effects of infection on host boldness, exploration and activity using rainbow trout Oncorhynchus mykiss and its trematode parasite Diplostomum pseudospathaceum, which infects a central sensory organ of the fish, the eye lens. Contrary to our expectation, infection did not change the withi…
Data from: Host infection history modifies co-infection success of multiple parasite genotypes
2016
1. Co-infections by multiple parasite genotypes are common and have important implications for host-parasite ecology and evolution through within-host interactions. Typically, these infections take place sequentially and therefore, the outcome of co-infection may be shaped by host immune responses triggered by previous infections. For example, in vertebrates specific immune responses play a central role in protection against disease over the course of life, but co-infection research has mostly focused on previously uninfected individuals. 2. Here, we investigated whether sequential exposure and activation of host resistance in rainbow trout Oncorhynchus mykiss affects infection success and …
Data from: Learned parasite avoidance is driven by host personality and resistance to infection in a fish–trematode interaction
2016
Cognitive abilities related to the assessment of risk improve survival. While earlier studies have examined the ability of animals to learn to avoid predators, learned parasite avoidance has received little interest. In a series of behavioural trials with the trematode parasite Diplostomum pseudospathaceum, we asked whether sea trout (Salmo trutta trutta) hosts show associative learning in the context of parasitism and if so, whether learning capacity is related to the likelihood of infection mediated through host personality and resistance. We show that animals are capable of learning to avoid visual cues associated with the presence of parasites. However, avoidance behaviour ceased after …
Eye fluke-induced cataract formation in fish: quantitative analysis using an ophthalmological microscope
2004
We examined the parasite-induced cataract formation in rainbow trout (Oncorhynchus mykiss) using slit-lamp microscopy to determine the relationship between cataract intensity and number of Diplostomum spathaceum parasites that were established in the lens. Cataract intensity increased significantly with parasite burden, but was also affected by the pattern of exposure to the parasite cercariae. The slit-lamp methodology proved useful in scoring the cataracts since it provides a 3-dimensional view into the lens and gives an actual picture of the location and intensity of the cataracts, which allows detailed investigations of mechanisms underlying cataract formation in various fish species. P…