17 research outputs found
Engineering in its social context : farmer participation in the Betsiboka irrigation system, Madagascar
Bauerliche Nutzergruppen in der Bewasserungslandwirtschaft: das Betsiboka-projekt in Madagaskar
Understanding the (Mega-)Urban from the Rural: Non-Permanent Migration and Multi-Locational Households
Westafrikaprojekt: Integratives Management-Projekt fuer einen Effizienten und Tragfaehigen Umgang mit Suesswasser (IMPETUS). Forschung und Praxis im Dialog Endbericht ueber die Vorstudie
SIGLEAvailable from TIB Hannover: F03B841 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung, Berlin (Germany)DEGerman
Temporary rural–rural labor migration from Quarit District, Northwest Ethiopia: a search for the determinants
How does Relationship-Based Governance Accommodate New Entrants? Evidence from the Cycle Rickshaw Rental Market
The Missing Link Between Urban and Rural Development: Lessons from Iraqi Kurdistan Region
Host and Environmental Influences on Development of Disease
While many myxozoan parasites produce asymptomatic infections in fish
hosts, several species cause diseases whose patterns of prevalence and
pathogenicity are highly dependent on host and environmental factors.
This chapter reviews how these factors influence pathogenicity and
disease prevalence. Influential host factors include age, size and nutritional
state. There is also strong evidence for host strains that vary in resistance
to infection and that there is a genetic basis for resistance. A lack of
co-evolutionary processes appears to generally underly the devastating
impacts of diseases caused by myxozoans when introduced fish are
exposed to novel parasites (e.g. PKD in rainbow trout in Europe) or when
native fish are exposed to an introduced parasite (e.g. whirling disease in
North America). Most available information on abiotic factors relates to
water temperature, which has been shown to play a crucial role in several
host parasite systems (e.g. whirling disease, PKD) and is therefore of
concern in view of global warming, fish health and food sustainability.
Eutrophication may also influence disease development. Abiotic factors
may also drive fish disease via their impact on parasite development in
invertebrate hosts