On the bionomics ofCrepidostomum metoecus(Braun, 1900) andCrepidostomum farionis(Müller, 1784) (Trematoda: Allocreadiidae)

Parasitology ◽  
1968 ◽  
Vol 58 (2) ◽  
pp. 307-324 ◽  
Author(s):  
J. B. E. Awachie
Keyword(s):  
Salmo Trutta ◽  
Time Lag ◽  
Ecological Factors ◽  
Life Cycles ◽  
Trophic Factors ◽  
Annual Cycles ◽  
Cottus Gobio ◽  
The United Kingdom ◽  
North Wales ◽  
History Of

The life-cycles of the two species ofCrepidostomumoccurring in a stream in North Wales are investigated. Both species share the same arthropod and definitive hosts, viz.Gammarus pulexandSalmo trutta, respectively, but have different molluscan hosts, viz.:Lymnaea peregraforC. metoecusandPisidium casertanumforC. farionis.C. metoecusandC. farionishave annual cycles, hence periodicity of occurrence in their hosts. InC. metoecusthe dynamics of occurrence in the three hosts are correlated. The inverse relationship inG. pulexandS. truttaas well as the existence of a time-lag of 3–4 months between the establishment of this worm inG. pulexand inS. truttaare discussed.Neither premunition nor age-resistance occurs in the parasitization ofS. truttaandG. pulexbyC. metoecus. The increase in the rate and degree of infestation with the age and length of fish, except in the oldest and longest group, is shown to be due to trophic factors.C. metoecusis more abundant and widely distributed in the stream thanC. farionis. This fact is associated with the occurrence of their molluscan hosts.Experimental observations were made on the stages in the life-history ofC. metoecus, including the mode of emergence of the cercaria, invasion of shrimps and encystment, as well as development of the metacercariae inG. pulex.More cercariae are shed by day and at higher temperatures, and they live for about 5 days at 8 °C. The metacercaria undergoes considerable development before becoming infective.C. metoecusdoes extensive damage toL. peregra, has no observed ill-effect on trout, and apparently affects the life-span of shrimps adversely only in cases of very heavy infestations.The non-parasitization ofCottus gobioby the two flukes is probably due to the prevailing ecological factors.My thanks are due to Professor H. B. N. Hynes and Dr J. C. Chubb for many helpful criticisms at all stages of this study; to Miss Joan Venn for helping with the sampling programme; and the Commonwealth Scholarship Commission in the United Kingdom for financial support.

Observations on Cyathocephalus truncatus Pallas, 1781 (Cestoda: Spathebothriidea) in its Intermediate and Definitive Hosts in a Trout Stream, North Wales

1966 ◽  
Vol 40 (1-2) ◽  
pp. 1-10 ◽  
Author(s):  
J. B. E. Awachie
Keyword(s):  
Brown Trout ◽  
Annual Cycle ◽  
Salmo Trutta ◽  
Feeding Habits ◽  
Age Groups ◽  
Older Age ◽  
Cottus Gobio ◽  
North Wales ◽  
Food And Feeding

Of the three species of fish which live in Afon Terrig (Salmo trutta, Cottus gobio and Nemacheilus barbatula), only S. trutta was infected by Cyathocephalus truncatus. The parasite has a clear annual cycle and hence a periodicity of occurrence in the brown trout.No age resistance of fish to infection by C. truncatus is found. The increase of incidence with age among l+—3+ year-old fish and decrease in the older age groups are correlated with the variation in the food and feeding habits of trout with age.

The population dynamics of the monogenean gill parasite Discocotyle sagittata Leuckart on Windermere trout, Salmo trutta, L.

Parasitology ◽  
1965 ◽  
Vol 55 (4) ◽  
pp. 667-694 ◽  
Author(s):  
J. E. Paling
Keyword(s):  
Population Dynamics ◽  
Population Study ◽  
Salmo Trutta ◽  
Ecological Factors ◽  
Life Cycles ◽  
Lake Ladoga ◽  
Coregonus Lavaretus ◽  
One Year ◽  
Fish Hosts ◽  
Relevant Work

Relatively little is known of the way in which the populations of monogenean parasites are related to the behaviour and physiology of their hosts or how such populations vary in composition over the year. Bychowsky (1957, trans. Hargis, 1961, p. 108) has described the results of studies upon six different fish hosts and parasites, while Llewellyn (1962) has studied two other species of Monogenea living on one host species. In all these investigations, the various ecological factors which influence the life cycles of the parasites have been determined.Dogiel, Petrushevski & Polyanski (1961, p. 14) referred to a previous population study of Discocotyle sagittata on a host Coregonus lavaretus in Lake Ladoga, Russia. The parasite was said to breed in July and August, while in September broods of young and old parasites overlapped. The large individuals disappeared in October and November and this ‘death of the older generation’ was taken to indicate that the parasites had a life span of only one year.The only relevant work available when the present study was commenced was the population study of the monogeneans Gastrocotyle trachuri and Pseudaxine trachuri by Llewellyn and as this concerned a marine host, it was of obvious interest to investigate the population dynamics of a parasite of a freshwater fish. Discocotyle sagittata was chosen because the biology of the British host, the brown trout (a different host from that in the Russian study of Discocotyle), has been intensively studied for many years. It was thought that this would be of advantage in attempting to relate any seasonal fluctuations in the parasite population to the biology of the host.

The ecology of Echinorhynchus truttae Schrank, 1788 (Acanthocephala) in a trout stream in North Wales

Parasitology ◽  
1965 ◽  
Vol 55 (4) ◽  
pp. 747-762 ◽  
Author(s):  
J. B. E. Awachie
Keyword(s):  
Intermediate Host ◽  
Salmo Trutta ◽  
Ecological Factors ◽  
Final Host ◽  
The Other ◽  
Developmental Cycle ◽  
Simultaneous Operation ◽  
Physiological Factors ◽  
North Wales ◽  
Sampling Points

Periodicity of occurrence in the final host has been observed in only a few of the known Acanthocephala of fish (Van Cleave, 1916; Steinstrasser, 1936; Komarova, 1950; Shulman & Shulman-Albova, 1953). The periodicity appears to be due to the simultaneous operation of a complex of physiological, developmental and ecological factors.In the present investigation a detailed study has been made of both the occurrence and the developmental cycle of Echinorhynchus truttae in its hosts in a small trout stream, Afon Terrig, in North Wales. An attempt has also been made to ascertain to what extent some of the various and varying ecological and physiological factors influenced the incidence, degree of parasitization and the development of the worm in nature.Samples of the intermediate host, Gammarus pulex pulex L., and the final host the brown trout, Salmo trutta L., were taken monthly at three points or stations where the stream was readily accessible. Station I was at Rhydtalog as far upstream as practicable. Station III was at the opposite end of the stream near Caegwydd and station II was about mid-way between the other two sampling points. To ensure that each host sample was examined in as fresh a condition as possible, autopsy of the intermediate host was completed before the definitive host was taken.Within the first week of each month from November 1961 to January 1963, shrimps were taken from over a stretch of about 30 m at each station.

History of political and civil rights of women in the United Kingdom

2019 ◽  
Vol 2019 (11) ◽  
pp. 135-139
Author(s):  
Maria Zhukova ◽  
Elena Maystrovich ◽  
Elena Muratova ◽  
Aleksey Fedyakin
Keyword(s):  
United Kingdom ◽  
Civil Rights ◽  
The United Kingdom ◽  
History Of

Charles de Gaulle and European Community

2020 ◽  
Vol 2020 (10-3) ◽  
pp. 70-81
Author(s):  
David Ramiro Troitino ◽  
Tanel Kerikmae ◽  
Olga Shumilo
Keyword(s):  
World War Ii ◽  
European Community ◽  
World War ◽  
Charles De Gaulle ◽  
The United Kingdom ◽  
History Of ◽  
The Common ◽  
Post War ◽  
De Gaulle

This article highlights the role of Charles de Gaulle in the history of united post-war Europe, his approaches to the internal and foreign French policies, also vetoing the membership of the United Kingdom in the European Community. The authors describe the emergence of De Gaulle as a politician, his uneasy relationship with Roosevelt and Churchill during World War II, also the roots of developing a “nationalistic” approach to regional policy after the end of the war. The article also considers the emergence of the Common Agricultural Policy (hereinafter - CAP), one of Charles de Gaulle’s biggest achievements in foreign policy, and the reasons for the Fouchet Plan defeat.

Volunteering in hospice and palliative care in the United Kingdom

2018 ◽  
Author(s):  
Ros Scott
Keyword(s):  
Palliative Care ◽  
United Kingdom ◽  
Care Services ◽  
The United Kingdom ◽  
Strategic Direction ◽  
Palliative Care Services ◽  
History Of ◽  
The Uk ◽  
Hospice And Palliative Care ◽  
Changing Role

This chapter explores the history of volunteers in the founding and development of United Kingdom (UK) hospice services. It considers the changing role and influences of volunteering on services at different stages of development. Evidence suggests that voluntary sector hospice and palliative care services are dependent on volunteers for the range and quality of services delivered. Within such services, volunteer trustees carry significant responsibility for the strategic direction of the organiszation. Others are engaged in diverse roles ranging from the direct support of patient and families to public education and fundraising. The scope of these different roles is explored before considering the range of management models and approaches to training. This chapter also considers the direct and indirect impact on volunteering of changing palliative care, societal, political, and legislative contexts. It concludes by exploring how and why the sector is changing in the UK and considering the growing autonomy of volunteers within the sector.

Disability and Work in South Asia and the United Kingdom

2018 ◽  
Author(s):  
Jane Buckingham
Keyword(s):  
Low Socioeconomic Status ◽  
Industrial Revolution ◽  
Economic Status ◽  
Low Socioeconomic ◽  
Disability History ◽  
The United Kingdom ◽  
Indian Experience ◽  
The Social ◽  
History Of ◽  
Western View

Historical analyses, as well as more contemporary examples of disability and work, show that the experience of disability is always culturally and historically mediated, but that class—in the sense of economic status—plays a major role in the way impairment is experienced as disabling. Although there is little published on disability history in India, the history of the Indian experience of caste disability demonstrates the centrality of work in the social and economic expression of stigma and marginalization. An Indian perspective supports the challenge to the dominant Western view that modern concepts of disability have their origins in the Industrial Revolution. Linkage between disability, incapacity to work, and low socioeconomic status are evident in India, which did not undergo the workplace changes associated with industrialization in the West.

Sign in / Sign up

Export Citation Format

Share Document