Int J Parasitol Parasites Wildl
August 2024
We here describe the location of anisakid third stage larvae in Atlantic herring L. caught in the North Sea in August 2023. We further demonstrate how industrial processing (mechanical gutting, removal of entrails, head, tail, hypaxial anterior musculature and vertebral column) reduces the overall infection and worm load in the musculature.
View Article and Find Full Text PDFSeveral biocides are widely used in rainbow trout aquaculture against various ectoparasites and ectobionts, but the inflammation induced in treated fish is less well described. Dose-response studies were conducted to elucidate the effects on rainbow trout (gills and fins) induced by a series of biocides including formalin, hydrogen peroxide (H2O2), peracetic acid (PAA) and the surfactant SPH6, which was isolated from the bacterium Pseudomonas H6. The compounds have documented antiparasitic effects, but the specific effects on fish needs further documentation.
View Article and Find Full Text PDFDuring recent years, we have observed an increasing occurrence of cercarial dermatitis in Denmark. We here describe 5 new cases from 2019 to 2020 associated with bathing in lakes Esrum sø, Furesø, and Ringen with emphasis on clinical symptoms and their relation to previous exposure to bird schistosome cercariae. In 2020, 2 patients from Furesø suffered from different severity of clinical symptoms after morning bathing in the same lake.
View Article and Find Full Text PDFEye flukes in fish are common in freshwater lakes. Fish become infected by the penetration of cercariae released from freshwater snails, and high infection pressures may be associated with mortalities in a Danish lake. Examination of two other freshwater lakes, combined with laboratory study, supported the notion.
View Article and Find Full Text PDFBackground: Digenean trematodes are parasitic platyhelminths that use several hosts in their life cycles and are thereby embedded in various ecosystems affected by local environmental conditions. Their presence in a habitat will reflect the presence of different host species and, as such, they can serve as ecological indicators. Only limited information on the occurrence of trematodes and their link to other trophic levels in the Danish freshwater ecosystems is currently available.
View Article and Find Full Text PDFTrichuris trichiura and T. suis are whipworms of humans and pigs, respectively, but it has recently been suggested that humans may be infected with multiple genotypes or species of Trichuris and cross-infection with Trichuris of pig origin has also been reported. In addition, the species status of Trichuris in non-human primates is unsettled and it is unknown how many whipworm species we share with other primates.
View Article and Find Full Text PDFBackground: Cercarial dermatitis (swimmer's itch) caused by bird schistosome cercariae, released from intermediate host snails, is a common disorder also at higher latitudes. Several cases were observed in the artificial Danish freshwater Ringen Lake frequently used by the public for recreational purposes. The lake may serve as a model system when establishing a risk analysis for this zoonotic disease.
View Article and Find Full Text PDFGill parasitic infections challenge farming of rainbow trout (Oncorhynchus mykiss, Walbaum) in freshwater facilities. Apart from flagellates (Ichthyobodo, (Pinto) and ciliates (Ichthyophthirius (Fouquet), Ambiphrya (Raabe), Apiosoma (Blanchard), Trichodinella (Sramek-Husek) and Trichodina (Ehrenberg)), we have shown that amoebae are prevalent in Danish trout farms. Gills were isolated from farmed rainbow trout in six fish farms (conventional and organic earth pond and recirculated systems) and placed on non-nutrient agar (NNA) moistened with modified Neff's amoeba saline (AS) (15°C).
View Article and Find Full Text PDFSwimmer's itch, or cercarial dermatitis, is a waterborne non-communicable skin condition caused by schistosome cercariae released by aquatic snails. Cercarial dermatitis appears worldwide, but may be caused by different trematode species. The itchy maculopapular rash develops on exposed areas of the skin and typically resolves within 1-3 weeks.
View Article and Find Full Text PDFFish Shellfish Immunol
October 2019
Tightened regulations and an environmentally friendly approaches in fish production have greatly reduced the use of antibiotics but green solutions are continuously being explored. The use of functional feed may have a potential in the aquaculture sector in securing biomass and minimizing the loss from disease. In the present study, we tested the concept that blood from the fish slaughterhouse can be used for mass purification of specific antibodies which subsequently can be used for feeding fish and thereby confer protection against diseases.
View Article and Find Full Text PDFInfection of rainbow trout with the parasitic ciliate Ichthyopthirius multifiliis induces differential responses in gills, skin and spleen. A controlled experimental infection was performed and expression of immune-relevant genes in skin, gills, and spleen were recorded by qPCR at day 1 and 8 after parasite exposure. Infection induced a marked reaction involving regulation of innate and adaptive immune genes in rainbow trout at day 8 post-infection.
View Article and Find Full Text PDFCK11 is a rainbow trout () CC chemokine phylogenetically related to both mammalian CCL27 and CCL28 chemokines, strongly transcribed in skin and gills in homeostasis, for which an immune role had not been reported to date. In the current study, we have demonstrated that CK11 is not chemotactic for unstimulated leukocyte populations from central immune organs or mucosal tissues but instead exerts a potent antimicrobial activity against a wide range of rainbow trout pathogens. Our results show that CK11 strongly inhibits the growth of different rainbow trout Gram-positive and Gram-negative bacteria, namely , subsp.
View Article and Find Full Text PDFThe parasite Ichthyophthirius multifiliis infecting skin, fins and gills of a wide range of freshwater fish species, including rainbow trout, is known to induce a protective immune response in the host. Although a number of studies have reported activation of several immune genes in infected fish host, the immune response picture is still considered incomplete. In order to address this issue, a comparative transcriptomic analysis was performed on infected versus uninfected rainbow trout gills and it showed that a total of 3352 (7.
View Article and Find Full Text PDFThe understanding of the epidemiology of canine parasitic infections is necessary for an efficient control program to minimize the risk of zoonotic transmission. The objectives of this study were (1) to determine the prevalence of canine gastrointestinal helminths and protozoa in Basra province, Southern Iraq, and (2) to identify the association of epidemiological characteristics (age, breed, gender, and feed type) of dogs with the parasitic infections. A total of 93 fecal samples, collected in the period from December 2014 to June 2015, were examined macroscopically and microscopically for the presence of worm eggs and protozoal oocysts, using centrifugal flotation method.
View Article and Find Full Text PDFVaccination of rainbow trout against Enteric Redmouth Disease (ERM) caused by Yersinia ruckeri can be successfully performed by administering vaccine (a bacterin consisting of formalin killed bacteria) by immersion, bath or injection. Booster immunization is known to increase the protection of fish already primed by one of these vaccination methods. Oral vaccination of trout (administering vaccine in feed) is an even more convenient way of presenting antigen to the fish but the effect of an oral booster has not previously been described in detail.
View Article and Find Full Text PDFA significant increase in the infection level of Baltic cod Gadus morhua with the anisakid nematode larvae Contracaecum osculatum and Pseudoterranova decipiens has been recorded during recent years due to the expanding local population of grey seals Halichoerus grypus, which act as final hosts for these parasites. Here, we report from an investigation of 368 cod (total length [TL] 6-49 cm; caught in ICES Subdivision 25) that the infection level of juvenile cod (TL 6-30 cm) with larvae of C. osculatum and P.
View Article and Find Full Text PDFBackground: Trichuris suis and T. trichiura are two different whipworm species that infect pigs and humans, respectively. T.
View Article and Find Full Text PDFEnteric redmouth disease (ERM) caused by the fish pathogen Yersinia ruckeri is a major threat to freshwater production of rainbow trout (Oncorhynchus mykiss) throughout all life stages. Injection vaccination of rainbow trout against Y. ruckeri infection has been shown to confer better protection compared to the traditionally applied immersion vaccination.
View Article and Find Full Text PDFThe whipworms Trichuris trichiura and Trichuris suis in humans and pigs, respectively, are believed to be two different species yet closely related. Morphologically, adult worms, eggs and larvae of the two species are indistinguishable. The aim of this study was to examine the genetic variation of Trichuris sp.
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