Spore-forming parasites infecting muscles of freshwater fishes : ecology and epidemiology
Fish parasites may potentially harm fisheries and aquaculture. Infected fish are
unusable, even though they would not pose a direct risk to human health. The
aim of this thesis was to investigate the ecology and epidemiology of three
previously unknown or poorly known spore-forming parasites infecting
muscles of economically important fish species. The first novel microsporidian
species, here described as Microsporidium luciopercae, was found from pike-perch (Sander lucioperca) and European perch (Perca fluviatilis) and formed
opaque-looking patches in the muscles. The second novel microsporidian
species, Myosporidium spraguei, was found from pike-perch and burbot (Lota lota)
and occurred within xenomas in the musculature. The third muscle-dwelling
parasite, Henneguya zschokkei (Cnidaria), formed white plasmodia in the muscle
of whitefish (Coregonus lavaretus). Among the six study lakes, the prevalence of
M. luciopercae in wild pike-perch and perch varied from 0 to 1 %, while M.
spraguei was more common (prevalence of 5–26 % in pike-perch and 65 % in
burbot). M. spraguei was strongly aggregated and most abundant in the middle-sized (37–45 cm) pike-perch and in larger burbot (> 35 cm), but the infection
was not related to host sex, sampling season or host condition. In the case of H.
zschokkei, in two inland fish farms, one year-old whitefish were virtually
uninfected, but the prevalence of infection was higher in 2 and 3 year old fish
(up to 36 % of 3 year old fish were infected). New infections appeared
seasonally in July-August. Neither the size of plasmodia nor the proportion of
different plasmodium types changed from 2 to 3 year old fish, suggesting slow
development of H. zschokkei in whitefish. However, the proportion of infected
fish with melanised plasmodia increased with fish age, suggesting an age-dependent host response against this strongly aggregated parasite.
...
![showless](/themes/JYX2//images/showless.png)
![showmore](/themes/JYX2//images/showmore.png)
Publisher
University of JyväskyläISBN
978-951-39-7109-0ISSN Search the Publication Forum
1456-9701Keywords
Metadata
Show full item recordCollections
- Väitöskirjat [3515]
License
Related items
Showing items with similar title or keywords.
-
Rearing background and exposure environment together explain higher survival of aquaculture fish during a bacterial outbreak
Räihä, Ville; Sundberg, Lotta-Riina; Ashrafi, Roghaieh; Hyvärinen, Pekka; Karvonen, Anssi (Wiley-Blackwell Publishing Ltd., 2019)1.Parasitic diseases represent one of the greatest challenges for aquaculture worldwide and there is an increasing emphasis on ecological solutions to prevent infections. One proposed solution is enriched rearing, where ... -
Sequential infection can decrease virulence in a fish‐bacterium‐fluke interaction : implications for aquaculture disease management
Karvonen, Anssi; Fenton, Andy; Sundberg, Lotta-Riina (Wiley-Blackwell Publishing, Inc., 2019)Hosts are typically infected with multiple strains or genotypes of one or several parasite species. These infections can take place simultaneously, but also at different times, i.e. sequentially, when one of the parasites ... -
Interactions between two parasites of brown trout (Salmo trutta) : Consequences of preinfection
Gopko, Mikhail; Chowdhury, Motiur; Taskinen, Jouni (John Wiley & Sons Ltd., 2018)Preinfection by one parasitic species may facilitate or by contrast hamper the subsequent penetration and/or establishment of other parasites in a host. The biology of interacting species, timing of preinfection, and dosage ... -
Relationship between the endangered freshwater pearl mussel Margaritifera margaritifera, its salmonid host and co-infectants
Chowdhury, M. Motiur R. (Jyväskylän yliopisto, 2018) -
The influence of infective dose, nutrient availability and coinfection on virulence of Flavobacterium columnare : implications of intensive aquaculture on opportunistic infections
Kinnula, Hanna (University of Jyväskylä, 2016)Ecological factors are known to affect disease dynamics and even lead to disease emergence. Especially in opportunistic, environmentally transmitted pathogens, the environment may significantly contribute to pathogen ...