Anisakis simplex larvae, commonly found in marine fish, cause anisakiasis in humans, resulting in gastric to gastro-allergic symptoms. Despite known health risks, the impact of Anisakidae larvae on fish hosts is less understood. This study aimed to investigate this interaction by assessing the feeding strategy of A.
View Article and Find Full Text PDFTo construct robust biogeochemical models for application to marine-based aquaculture settings, careful selection of appropriate model parameters is necessary. This study used an experimental approach to establish biomarkers of farm and marine-derived organic matter, and to derive isotopic turnover rates, and trophic discrimination factors specific to aquaculture associated food webs. A shift towards a farm-derived resource base resulted in consumer tissues more depleted in the carbon-13 isotope (indicated by more negative δC values) and a higher proportion of oleic acid, linoleic acid, and alpha-linoleic acid in the fatty acid profile of consumers over time.
View Article and Find Full Text PDFWhen ecosystems are under severe pressure or environments change, trophic position and intraspecific niche width may decrease or narrow, signalling that conservation action is required. In New Zealand, alpine and subalpine ecosystems have been extensively modified through farming since 19th-century European settlement, with consequences for indigenous species such as the kea Nestor notabilis. We investigated feather stable isotope values in the kea and predicted a lower trophic position in modern kea populations, to reflect reduced lowland habitat and a mixed diet with more plant material.
View Article and Find Full Text PDFUnderstanding how marine food webs are affected by anthropogenic stressors is an important steppingstone toward the improved management of natural resources. Stable isotope analysis of historical and modern samples spanning a century indicated that the niche width of an exploited fish community increased after the expansion of New Zealand fisheries. Since the 2000s most species increased their reliance on food webs supported by pelagic production, compared to coastal production supported by macroalgae, and shifted to a higher trophic level.
View Article and Find Full Text PDFThe New Zealand huia (Heteralocha acutirostris) had the most extreme bill sexual dimorphism among modern birds. Given the quick extinction of the species, the cause of the dimorphism could only be hypothesised to reflect different trophic niches and reduce male/female competition. We tested that hypothesis by combining museum specimens, geometric morphometrics, and isotopic analyses.
View Article and Find Full Text PDFEvery internet search query made out of curiosity by anyone who observed something in nature, as well as every photo uploaded to the internet, constitutes a data point of potential use to scientists. Researchers have now begun to exploit the vast online data accumulated through passive crowdsourcing for studies in ecology and epidemiology. Here, we demonstrate the usefulness of iParasitology, i.
View Article and Find Full Text PDFLocal differences in trophic structure and composition of organic matter subsidies can influence the capacity of soft sediment communities to assimilate recycled organic matter from processes such as salmon farm enrichment. The present study combines biochemical analysis with biomass density information on soft sediment taxa collected within the depositional footprint of salmon farms and at reference sites in the Marlborough Sounds, New Zealand. Distinct biochemical signatures confirmed that the flux of organic matter from salmon farms was an important subsidy for soft sediment communities.
View Article and Find Full Text PDFBackground: We previously reported that ketamine has anxiolytic effects in patients with treatment-resistant generalized anxiety and social anxiety disorders.
Aims: The purpose of this study was to replicate our earlier report about ketamine's anxiolytic activity, using a more robust study design.
Methods: This was a double-blind, psychoactive-controlled ascending dose study in 12 patients with treatment-resistant generalized anxiety and social anxiety disorders who were not currently depressed.