Effects of cadmium and zinc toxicity on orientation behaviour of Echinoparyphium recurvatum (Digenea: Echinostomatidae) cercariae

Morley, N.J.; Crane, Mark; Lewis, J. W.

doi:10.3354/dao056089

Cited by 14 publications

(8 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similarly, Cross et al (2005), when examining the swimming behaviour of Cryptocotyle lingua (Creplin, 1825) cercariae living in a polluted environment, found that they displayed a slower horizontal swimming rate and reduced longevity compared to cercariae released in a cleaner environment. Another similar finding was recorded by Morley et al (2003) on the cercariae of Echinoparyphium recurvatum (Digenea: Echinostomatidae) living within rediae parasitizing molluscs having accumulated toxic substances (cadmium and zinc). The free-living stages of Digenea have been highlighted as potentially good biological indicators of pollution with heavy metals (Lafferty, 1997).…”

Section: Resultssupporting

confidence: 86%

Digenean diversity in labrid fish from the Bay of Bizerte in Tunisia

Abdalah

Elbohli²,

Maamouri³

2009

J. Helminthol.

View full text Add to dashboard Cite

Six species of digeneans (Proctoeces maculatus (Looss, 1901), Helicometra fasciata (Odhner, 1902), Helicometra pulchella (Odhner, 1902), Macvicaria alacris (Looss, 1901), Peracreadium genu (Nicoll, 1909) and Zoogonus rubellus (Olson, 1868)) were found for the first time in labrid fish (Symphodus tinca (Linnaeus, 1758), Labrus merula (Linnaeus, 1758) and Labrus viridis (Linnaeus, 1758)) from the Bay of Bizerte. Except for P. maculatus and Z. rubellus, which are limited to the rectum, these helminths colonize the entire digestive tract. The study of the seasonal prevalence, abundance and mean intensity shows that three parasites, P. maculatus, H. fasciata and P. genu are present throughout the year while H. pulchella, M. alacris and Z. rubellus are less frequent and appear only in spring (H. pulchella and M. alacris) or in spring and summer (Z. rubellus). The levels of infection and digenean faunal diversity in labrid fish from the Tunisian coasts are generally lower than those from localities within the western Mediterranean.

show abstract

Section: Resultssupporting

confidence: 86%

Digenean diversity in labrid fish from the Bay of Bizerte in Tunisia

Abdalah

Elbohli²,

Maamouri³

2009

J. Helminthol.

View full text Add to dashboard Cite

show abstract

“…However, in a reversed illumination experiment L. peregra were active in the dark without E. recurvatum cercariae emerging (unpublished observations), indicating that emergence is essentially invoked by illumination and the release of cercariae is made possible by movements of the snail host, exposing the preferred cercarial exit region to the environment. Echinoparyphium recurvatum cercariae may also directly respond to illumination within the intramolluscan environment, as once emerged into water they demonstrate both phototactic and geotactic orientation behaviour (McCarthy, 1999c; Morley et al , 2003b). The correlation of emergence with first intermediate host activity will also synchronize maximum cercarial production with the daily activity of second intermediate molluscan hosts.…”

Section: Discussionmentioning

confidence: 99%

The effects of host size and temperature on the emergence ofEchinoparyphium recurvatumcercariae fromLymnaea peregraunder natural light conditions

2010

View full text Add to dashboard Cite

The production of cercariae from their snail host is a fundamental component of transmission success in trematodes. The emergence of Echinoparyphium recurvatum (Trematoda: Echinostomatidae) cercariae from Lymnaea peregra was studied under natural sunlight conditions, using naturally infected snails of different sizes (10-17 mm) within a temperature range of 10-29 degrees C. There was a single photoperiodic circadian cycle of emergence with one peak, which correlated with the maximum diffuse sunlight irradiation. At 21 degrees C the daily number of emerging cercariae increased with increasing host snail size, but variations in cercarial emergence did occur between both individual snails and different days. There was only limited evidence of cyclic emergence patterns over a 3-week period, probably due to extensive snail mortality, particularly those in the larger size classes. Very few cercariae emerged in all snail size classes at the lowest temperature studied (10 degrees C), but at increasingly higher temperatures elevated numbers of cercariae emerged, reaching an optimum between 17 and 25 degrees C. Above this range emergence was reduced. At all temperatures more cercariae emerged from larger snails. Analysis of emergence using the Q10 value, a measure of physiological processes over temperature ranges, showed that between 10 and 21 degrees C (approximately 15 degrees C) Q10 values exceeded 100 for all snail size classes, indicating a substantially greater emergence than would be expected for normal physiological rates. From 14 to 25 degrees C (approximately 20 degrees C) cercarial emergence in most snail size classes showed little change in Q10, although in the smallest size class emergence was still substantially greater than the typical Q10 increase expected over this temperature range. At the highest range of 21-29 degrees C (approximately 25 degrees C), Q10 was much reduced. The importance of these results for cercarial emergence under global climate change is discussed.

show abstract

“…At concentrations as low as 10 mg/l the metals induced a more rapid change to negative phototaxis and positive geotaxis than controls, which was considered to be either a reflex response to the toxic environment or a by-product of the toxic action of the metals (Morley et al 2003 c). These changes in behaviour have been attributed to the binding of metals to areas associated with sensory receptors (Korner & Haas, 1998 ;Morley et al 2003 c), and histochemical studies on E. recurvatum appear to support this (Morley et al 2003 c). Furthermore, metals may also bind to other structures on the tegumental surface including glandular openings in the cephalic region, excretory pores and the mouth opening.…”

Section: Functional Biologymentioning

confidence: 99%

“…Autometallographic localisation of zinc on free-living digeneans using protocols devised byDanscher et al (1987) and modified byMorley et al (2003 c). Parasites were exposed to 10 000 mg/l Zn for 30 min.…”

mentioning

confidence: 99%

Pollution toxicity to the transmission of larval digeneans through their molluscan hosts

2003

View full text Add to dashboard Cite

The increased occurrence of pollutants in ecosystems is a continuing area of concern. It is known that numerous diseases of wild aquatic animals can occur with decreased or increased prevalences in areas associated with high or chronic levels of pollution. This may have serious implications for environmental health. There has consequently been an increasing number of laboratory and field studies on disease transmission under polluted conditions, especially focusing on digeneans of medical or economic importance. The effect of pollutants to the transmission of larval digeneans (miracidia, cercariae, metacercariae) and snail-digenean interactions is therefore considered. An overview and interpretation of the published literature on laboratory and field studies is provided. It is apparent from these studies that the influence of pollutants on digenean transmission is highly complex with much of the observed effects in the laboratory often masked by a complexity of other factors in the field. Future studies would benefit from a standardisation of experimental procedures, increasing the number of combined laboratory and field studies, and increasing the complexity of the experiments undertaken.

show abstract

Effects of cadmium and zinc toxicity on orientation behaviour of Echinoparyphium recurvatum (Digenea: Echinostomatidae) cercariae

Cited by 14 publications

References 15 publications

Digenean diversity in labrid fish from the Bay of Bizerte in Tunisia

Digenean diversity in labrid fish from the Bay of Bizerte in Tunisia

The effects of host size and temperature on the emergence ofEchinoparyphium recurvatumcercariae fromLymnaea peregraunder natural light conditions

Pollution toxicity to the transmission of larval digeneans through their molluscan hosts

Contact Info

Product

Resources

About