Search results for "Parasite hosting"
showing 6 items of 306 documents
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…
Isolation and characterization of microsatellite markers in the liver fluke (Fasciola hepatica)
2004
PRIMER NOTE; International audience; Six microsatellite markers were isolated from Fasciola hepatica, a re-emerging parasite that causes important veterinary and public health problems. In a sample of 52 liver flukes from a region of hyperendemicity (Bolivian Altiplano), five microsatellite were polymorphic. Our results showed that liver flukes present important genetic variability, suggesting a preferential outcrossing reproduction mode for this hermaphroditic parasite.
Sex and sexual ornamentation associated with survival of the cyprinid fish, Rutilus rutilus, under disease stress
2013
By conveying information of disease resistance, sexual signals may be used as cues for adaptive mate choice. Here we report observations on survival of laboratory-maintained, wild-collected, sexually mature, ready-to-spawn cyprinid fish, Rutilus rutilus (roach), under accidental epidemic attributed to Flavobacterium psychrophilum, diagnosed using species-specific PCR. The fish were maintained in a single tank. During the 27 days observation period, both the proportion of fish surviving the infection as well as the length-adjusted mean survival time of the fish that died was the highest among the high-ornamented males with large breeding tubercles, intermediary among the low-ornamented males…
Parasite avoidance behaviours in aquatic environments
2018
Parasites, including macroparasites, protists, fungi, bacteria and viruses, can impose a heavy burden upon host animals. However, hosts are not without defences. One aspect of host defence, behavioural avoidance, has been studied in the terrestrial realm for over 50 years, but was first reported from the aquatic environment approximately 20 years ago. Evidence has mounted on the importance of parasite avoidance behaviours and it is increasingly apparent that there are core similarities in the function and benefit of this defence mechanism between terrestrial and aquatic systems. However, there are also stark differences driven by the unique biotic and abiotic characteristics of terrestrial …
Author Correction: Evaluation of three methods for biomass estimation in small invertebrates, using three large disparate parasite species as model o…
2018
Invertebrate biomass is considered one of the main factors driving processes in ecosystems. It can be measured directly, primarily by weighing individuals, but more often indirect estimators are used. We developed two indirect and non-destructive approaches to estimate biomass of small invertebrates in a simple manner. The first one was based on clay modelling and the second one was based on image analysis implemented with open-source software. Furthermore, we tested the accuracy of the widely used geometric approximation method (third method). We applied these three different methods to three morphologically disparate model species, an acanthocephalan worm, a crustacean and a flatworm. To …
Phosphorus limitation enhances parasite impact: feedback effects at the population level
2014
Background Nutrient deficiency affects the growth and population dynamics of consumers. Endoparasites can be seen as consumers that drain carbon (C) or energy from their host while simultaneously competing for limiting resources such as phosphorus (P). Depending on the relative demands of the host and the parasite for the limiting nutrient, intensified resource competition under nutrient limitation can either reduce the parasite’s effect on the host or further reduce the fitness of the nutrient-limited host. So far, knowledge of how nutrient limitation affects parasite performance at the host population level and how this affects the host populations is limited. Results We followed the popu…