The Importance of the Acanthocephalan Polymorphus minutus as a Parasite of Domestic Ducks in the United Kingdom

The intestinal parasite Polymorphus minutus sometimes causes severe losses of domestic ducks, but more often birds on free range are unaffected although exposed to infection. The causes of this are examined and an attempt is made to explain it. The worm has no innate seasonal occurrence, but can survive for many months in the intermediate host, by which it can also be spread for long distances along streams. The veterinary implications of these findings are considered.

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Comparison of richness and diversity of macroparasite communities among eels from Nova Scotia, the United Kingdom and Australia

Parasitology ◽

10.1017/s0031182097001923 ◽

1998 ◽

Vol 116 (1) ◽

pp. 73-83 ◽

Cited By ~ 8

Author(s):

D. J. MARCOGLIESE ◽

D. K. CONE

Keyword(s):

United Kingdom ◽

Nova Scotia ◽

Intestinal Parasite ◽

Fish Fauna ◽

Species Number ◽

Component Community ◽

Parasite Communities ◽

The United Kingdom ◽

Tropical Conditions ◽

The Uk

Species richness and diversity of macroparasite assemblages were compared among American eels (Anguilla rostrata) from Nova Scotia, European eels (A. anguilla) from the United Kingdom (Kennedy, Bush & Aho, 1986; Esch et al. 1988; Kennedy, 1990, 1993), and Australian eels (A. reinhardtii) from Queensland (Kennedy, 1995). Community richness and diversity of the macroparasite fauna of American and European eels did not differ significantly for total parasite component communities, intestinal parasite component communities, and intestinal parasite infracommunities. The similarities in richness and diversity between the parasite communities of American and European eels are not surprising given the common, recent origin of these sister species. However, differences in species composition were noted between Nova Scotia and the UK. Both species of eels were infected by a nearly identical suite of specialists, but differences occurred in the species number and composition of generalist parasites. In addition, generalist species were rarely dominant in Nova Scotia, but commonly so in the UK. These differences can be attributed to the differences in the freshwater fish fauna and their parasites that occur between Nova Scotia and the UK. American and European eels are derived from a common ancestor and, whereas they have carried with them a common suite of specialist parasites during their brief period of independence, they acquired different suites of generalists apparently from their respective continental faunas after they diverged. In contrast, parasite communities of American and European eels were significantly less diverse and speciose than those of Australian eels regardless of scale (total component community, intestinal component community, intestinal infracommunity). These results support the notion that parasite communities have had more time to evolve and/or that tropical conditions have promoted parasite speciation in Australian eels.

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