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We report the results of investigations 2010 through 2023 of hymenopteran parasitoids associated with gall midges in Europe. A total of 242 collections of gall midges were made, from each of which one to several parasitoid species emerged, resulting in ca. 200 recorded parasitoid species and 267 host-parasitoid interaction records. The parasitoid families involved were Eulophidae (63 species), Platygastridae (56 species), Torymidae (34 species), Pteromalidae (31 species), Ceraphronidae (5 species), Eupelmidae (4 species), Eurytomidae (2 species) and Encyrtidae (1 species). As many as 159 interactions are reported for the first time, significantly enlarging our knowledge of gall midge – parasitoid interactions on the species level. Even more interesting, 51 host records are for parasitoid species for which no host was previously known. Similarly, 28 species of gall midge are reported as host to named parasitoids for the first time. Additionally, 91 parasitoid records were the first for the country in question. Differences between the rearing methods applied and their suitability for recording species with contrasting life histories, are discussed.

Fungal and arthropod consumers constitute the vast majority of global terrestrial biodiversity. Yet, the link from richness and composition of producer (plant) communities to the richness of consumer communities is poorly understood. Fungal and arthropod species richness could be a simple function of producer species richness at a site. Alternatively, it could be a complex function of chemical and structural properties of the producer species making up communities. We used databases on plant–fungus and plant–arthropod trophic links to derive the richness of consumer biota per associated plant species (coined link score). We assessed how well link scores could be predicted by simple attributes of plant species. Next, we used a multi-taxon inventory of 130 sites, representing all major habitat types in a country (Denmark), to investigate whether link scores summed over plant species in communities (coined link sum) could outperform simple plant species richness as predictor of fungal and arthropod richness at the sites. We found plant species' link scores for both fungi and arthropods to be positively related to plant size, regional occupancy, nativeness and ectomycorrhizal status. Link-based indices generally improved the prediction of richness of fungal and arthropod communities. For fungal communities, both observed link sum (from databases) and predicted link sum (from plant attributes) had high predictive power, while plant richness alone had none. For arthropod communities, predictive performance varied between functional groups. For both fungi and arthropods, richness predictions were further improved by considering abiotic habitat conditions. Our results underline the importance of plants as niche space for the megadiverse groups of arthropods and fungi. The plant–attribute approach holds promise for predicting local and regional consumer richness in areas of the world lacking detailed plant–consumer databases.

Inflammatory bowel disease (IBD) in developed countries is linked with elevated hygienic standards. One of the several factors involved in this question may be reduced exposure to the immunomodulatory effects of parasitic helminths. Several investigations on treatment of mice and humans with helminth-derived substances have supported this notion, but underlying mechanisms remain unclear. This study therefore dissects to what extent a series of immune-related genes are modulated in zebrafish with experimentally induced colitis following exposure to excretory-secretory (ES) products isolated from larval Anisakis, a widely distributed fish nematode. Adult zebrafish intrarectally exposed to the colitis-inducing agent TNBS developed severe colitis leading to 80% severe morbidity, but if co-injected (ip) with Anisakis ES products, the morbidity rate was 50% at the end of the experiment (48 hours post-exposure). Gene expression studies of TNBS-treated zebrafish showed clear upregulation of a range of genes encoding inflammatory cytokines and effector molecules and some induction of genes related to the adaptive response. A distinct innate-driven immune response was seen in both TNBS and TNBS + ES groups, but expression values were significantly depressed for several important pro-inflammatory genes in the TNBS + ES group, indicating protective mechanisms of Anisakis ES compounds on intestinal immunopathology in zebrafish.

Crohn’s disease and ulcerative colitis—inflammatory bowel diseases (IBD)—are chronic conditions with an inadequately understood pathogenesis. Employing a set of novel molecular markers in a gene expression assay (qPCR), we have used adult zebrafish to investigate two acute inflammatory models, induced by the haptenizing agents oxazolone and TNBS. In addition, goblet cell dynamics in the scales and intestine and 5-HT (serotonin) in intestinal tissues were investigated through optical projection tomography. Gene expression studies revealed a distinct and significant upregulation of proinflammatory cytokines, acute-phase reactants and metalloprotease 9 in both chemical models, primarily after 72 hours. In comparison, transcription factors and cytokines associated with Th1 and Th17 (Crohn’s) and Th2 (ulcerative colitis) were mainly not affected in this acute setting. However, elevated transcript levels were detected in Foxp3, IL-10 and T-bet, which are linked with tolerance and Tregs in mammals. Goblet cells in scales were depleted in both chemical models and in the intestine of oxazolone-treated fish. A marked 5-HT signal was noted in intestinal tissue of some chemically treated zebrafish. In conclusion, a distinct acute inflammatory reaction was induced in both chemical models. Further, oxazolone and TNBS did not result in clear-cut Th2 and Th1/Th17 pathway signaling at this early timepoint, but the applied molecular tools may provide further insight to the IBD pathogenesis and translational value of the IBD zebrafish model.

First records of twenty-three gall midge species in Denmark are reported: Asphondylia ervi Rübsaamen, Contarinia acetosellae Rübsaamen, C. viburnorum Kieffer, Dasineura astragalorum (Kieffer), D. fructum (Rübsaamen), D. harrisoni (Bagnall), D. lotharingiae (Kieffer), D. papaveris (Winnertz), D. saxifragae (Kieffer), D. traili (Kieffer), Herbomyia robusta Möhn, Jaapiella chelidonii Fedotova, Lasioptera arundinis Schiner, L. calamagrostidis Rübsaamen, Mayetiola festucae Ertel, M. phalaris Barnes, M. ventricola (Rübsaamen), Mycodiplosis coniophaga (Winnertz), Parallelodiplosis galliperda (Löw), Piceacecis abietiperda (Henschel), Rabdophaga strobilina (Bremi), Taxomyia taxi (Inchbald) and a probably undescribed species of Contarinia Rondani. Thus, 363 fully identified gall midge species are now documented from Denmark along with 25 species, which have been identified to genus level only. The species number per subfamily is 335 Cecidomyiinae (311 fully identified and 24 identified to the genus level only), 0 Winnertziinae and 14 Porricondyliinae (13 fully identified and one identified to the genus level only), 24 Micromyinae and 15 Lestremiinae.

Inflammatory bowel disease (IBD) is subdivided into ulcerative colitis and Crohn's disease, which are chronic disorders. Millions of persons throughout the Western world are affected by IBD, and the condition is associated with severe morbidity and reduced quality of life for afflicted persons. The etiology is complex and not fully understood. The zebra fish (Danio rerio) may serve as a model for elucidation of these inadequately understood mechanisms. Two hapten-mediated IBD-like models in zebra fish have been generated by using the chemicals oxazolone and TNBS dissolved in ethanol. From mammalian models it is known that oxazolone and TNBS can induce conditions mimicking ulcerative colitis (Th2 like response) and Crohn's disease (Th1/Th17 like response), respectively. Zebra fish (body weight 0.5 g) were divided into 4 groups (each with 2 replicates) and instilled rectally with H2O, ethanol, TNBS or oxazolone. Samples (intestine) were taken for realtime quantitative PCR. An array of TagMan assays was designed using Primer3Plus. All assays were checked by melting curve analysis in SYBR Green and by 3% agarose gel electrophoresis in order to ensure specificity. The assays include transcription factors and cytokines of different subsets of T-cell populations, cell markers etc. The 2-Ct method was used to estimate the fold change of gene expression relative to the H2O instilled group. Only results with p>0.05 and regulations >2 are discussed. The solvent ethanol, necessary for dissolving oxazolone and TNBS, itself up-regulates genes (T-bet, INF, IL-17A, TGF) primarily from the Th1/Th17 response but also IL-10 of the Th2 response. The gene expression pattern of the oxazolone and TNBS instilled groups were partly similar pointing primarily towards a Th2 response. TNF was the only Th1response specific gene up-regulated. In both groups the expression of 2 typically IBD markers IL-8 and Mmp9 were up-regulated whereas Myd88 seemed unaffected. In conclusion, as judg

Første danske fund af femten arter af galmyg dokumenteres, nemlig: Arthrocnodax fraxinellus (Meade), der er prædator på askeblomstgalmider på ask, Contarinia anthophthora (F. Löw), C. nicolayi (Rübsaamen), C. rumicis (Loew), C. umbellatarum Rübsaamen og Dasineura cardaminis (Winnertz), der fremkalder galler i blomsterknopper af henholdsvis mørk kongelys, almindelig bjørneklo, almindelig pimpinelle, vandkarse og vedbend, Dasineura dactylidis Metcalfe og Sitodiplosis dactylidis Barnes, der lever i blomsterstande af hundegræs, Dasineura inflata Stelter, der danner galler af frugthylstre på sylt-star, Planetella gallarum (Rübsaamen) og P. tarda (Rübsaamen), der begge fremkalder galler på bladskeder af tue-star, Jaapiella volvens Rübsaamen og Macrolabis lonicerae Rübsaamen, der danner galler i rullede blade af henholdsvis gul fladbælg og almindelig gedeblad, og endelig Wachtliella krumbholzi Stelter, der lever i svagt misdannede frugter af vrietorn. Med de fundne arter består den kendte danske galmyg-fauna af 320 fuldt identificerede arter, samt yderlige 24 arter, hvis identitet indtil videre kun er kendt på slægtsniveau.

Gennemgang af levnedsmiddelhygiejniske aspekter ved fiskeparasitter

Three salmonid fish species, Oncorhynchus mykiss, Salmo salar and Salmo trutta, were infected experimentally with the parasitic nematode Anisakis simplex (A. simplex) and the difference between in vivo behaviour of the nematode in the three fish species was investigated. Infection success rate differed between species. S. salar (Baltic salmon) showed the highest number of successfully established nematodes, whereas S. trutta (brown trout) and O. mykiss (rainbow trout) had a higher natural resistance. Microhabitat selection of nematodes differed according to fish species. In brown trout, A. simplex larvae were attached to the digestive tract (stomach, pyloric caeca, intestine), while the majority of larvae found in rainbow trout were located between the pyloric caeca. In Baltic salmon, nematodes were dispersed in and on spleen, head kidney, liver, swim bladder and musculature. Encapsulation and inflammatory cellular reactions differed accordingly. Histopathological and immunohistochemical studies using monoclonal antibodies raised against salmonid IgM, CD8 and MHCII were performed to detect the presence of immune cells around the infecting nematodes. None of the three fish species showed positive reactions for IgM-bearing cells in the inflammatory tissue connected with nematodes. CD8+ cells were detected in all three species and MHCII-bearing cells were found associated with encapsulated A. simplex in rainbow trout and brown trout, but not in Baltic salmon. Physiological, immunological and pathological implications of microhabitat differences are discussed.