Colonization, larval survival and epidemiology of the nematode Anguillicola crassus , parasitic in the eel, Anguilla anguilla , in Britain

Colonization, larval survival and epidemiology of the nematode Anguillicola crassus , parasitic... In late 1987, immature Anguillicola crassus were reported for the first time in Britain from eels from two river systems. By late 1988, gravid adults were present in a number of rivers in the east of England in two discrete centres of distribution: one in East Anglia correlated with the route taken by lorries exporting eels to the continent, and one in the R. Thames correlated with the import of eels to London. The parasite was firmly established in the R. Trent, where prevalence levels reached 100% in some places. Laboratory investigations showed that adult parasites and their eggs remained viable even after infected eels had been maintained for 4 weeks in 100% sea water. Hatching of eggs declined with increasing salinity, but was not totally inhibited by sea water. Survival and infectivity of freeliving second stage larvae were maximal in natural fresh water (95% survival for 4 months, and 50% still infective to copepod intermediate hosts after 70 days), but declined in alkaline water and with increased salinity. Nevertheless, in 100% sea water, 50% of larvae were still infective after 8 days. Specificity to the intermediate host was low, and eels of all sizes could be infected. These characteristics, plus a high reproductive potential, give the parasite exceptional colonization potential and ability, enabling it to survive natural movements of eels from catchment to catchment and to increase rapidly within a new locality. The ability of free‐living larvae to adhere to the substratum and survive in sea water enables them to survive in eel‐transport lorries from which they will not readily be removed by flushing, the normal cleansing procedure. It is concluded that there were two separate introductions of the parasite to Britain; via the eel import trade through London, and, totally unexpectedly, via the eel export trade in lorries traversing East Anglia. The parasite is now firmly established in Britain and will continue to spread by natural movements of eels but especially by human‐assisted movements of infected eels for stocking and market. This latter practice is recognized as a major factor in introducing and disseminating fish parasites. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Fish Biology Wiley

Colonization, larval survival and epidemiology of the nematode Anguillicola crassus , parasitic in the eel, Anguilla anguilla , in Britain

Journal of Fish Biology, Volume 36 (2) – Feb 1, 1990

Loading next page...
 
/lp/wiley/colonization-larval-survival-and-epidemiology-of-the-nematode-tGm0q4onwg
Publisher
Wiley
Copyright
Copyright © 1990 Wiley Subscription Services, Inc., A Wiley Company
ISSN
0022-1112
eISSN
1095-8649
D.O.I.
10.1111/j.1095-8649.1990.tb05588.x
Publisher site
See Article on Publisher Site

Abstract

In late 1987, immature Anguillicola crassus were reported for the first time in Britain from eels from two river systems. By late 1988, gravid adults were present in a number of rivers in the east of England in two discrete centres of distribution: one in East Anglia correlated with the route taken by lorries exporting eels to the continent, and one in the R. Thames correlated with the import of eels to London. The parasite was firmly established in the R. Trent, where prevalence levels reached 100% in some places. Laboratory investigations showed that adult parasites and their eggs remained viable even after infected eels had been maintained for 4 weeks in 100% sea water. Hatching of eggs declined with increasing salinity, but was not totally inhibited by sea water. Survival and infectivity of freeliving second stage larvae were maximal in natural fresh water (95% survival for 4 months, and 50% still infective to copepod intermediate hosts after 70 days), but declined in alkaline water and with increased salinity. Nevertheless, in 100% sea water, 50% of larvae were still infective after 8 days. Specificity to the intermediate host was low, and eels of all sizes could be infected. These characteristics, plus a high reproductive potential, give the parasite exceptional colonization potential and ability, enabling it to survive natural movements of eels from catchment to catchment and to increase rapidly within a new locality. The ability of free‐living larvae to adhere to the substratum and survive in sea water enables them to survive in eel‐transport lorries from which they will not readily be removed by flushing, the normal cleansing procedure. It is concluded that there were two separate introductions of the parasite to Britain; via the eel import trade through London, and, totally unexpectedly, via the eel export trade in lorries traversing East Anglia. The parasite is now firmly established in Britain and will continue to spread by natural movements of eels but especially by human‐assisted movements of infected eels for stocking and market. This latter practice is recognized as a major factor in introducing and disseminating fish parasites.

Journal

Journal of Fish BiologyWiley

Published: Feb 1, 1990

References

  • The occurrence of Bothriocephalus acheilognathi Yamaguti, 1934 ( B. gowkongensis ) (Cestoda: Pseudophyllidea) in the British Isles
    Andrews, Andrews; Chubb, Chubb; Coles, Coles; Dearsley, Dearsley

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off