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Traditional methods to identify bacterial pathogens involved in fish diseases are often slow and/or costly. Matrix-Assisted Laser Desorption Ionization Time-Of-Flight mass spectrometry (MALDI-TOF MS) is an established, fast, accurate and cost effective protein-based technique for identification of bacterial pathogens in human and veterinary laboratories, and has now also been developed for identification of bacterial fish pathogens. Based on analysis of colonies sampled directly from agar plate cultures, the MALDI-TOF technique generates a protein spectrum which is then compared against spectra, called reference spectra, stored in the MALDI-TOF databases. Since not all bacterial fish pathogens are covered in commercial databases, database-libraries are usually constructed locally for relevant reference strains/species. In this study, results from two collaborative projects, involving four European veterinary medicine institutes, are presented, focusing on supplementation of available spectra and validation of the MALDI-TOF MS technique for identification of several bacterial fish pathogens. Flavobacterium psychrophilum, F. columnare, Pseudomonas anguilliseptica, Renibacterum salmoninarum, Vibrio anguillarum and Yersinia ruckeri are examples of important bacterial fish pathogens that may be successfully identified to the species level by MALDI-TOF MS. On the contrary, identification of Aeromonas salmonicida to species level requires additional phenotypic or genetic analysis to arrive at a correct identification. In conclusion, MALDI-TOF MS has proven a fast, cost effective and accurate identification method for use in fish bacteriology, with a potential for further improvements.

The Scandinavian wolf population descends from only five individuals, is isolated, highly inbred and exhibits inbreeding depression. To meet international conservation goals, suggestions include managing subdivided wolf populations over Fennoscandia as a metapopulation; a genetically effective population size of Ne⩾500, in line with the widely accepted long-term genetic viability target, might be attainable with gene flow among subpopulations of Scandinavia, Finland and Russian parts of Fennoscandia. Analytical means for modeling Ne of subdivided populations under such non-idealized situations have been missing, but we recently developed new mathematical methods for exploring inbreeding dynamics and effective population size of complex metapopulations. We apply this theory to the Fennoscandian wolves using empirical estimates of demographic parameters. We suggest that the long-term conservation genetic target for metapopulations should imply that inbreeding rates in the total system and in the separate subpopulations should not exceed Δf=0.001. This implies a meta-Ne of NeMeta⩾500 and a realized effective size of each subpopulation of NeRx⩾500. With current local effective population sizes and one migrant per generation, as recommended by management guidelines, the meta-Ne that can be reached is ~250. Unidirectional gene flow from Finland to Scandinavia reduces meta-Ne to ~130. Our results indicate that both local subpopulation effective sizes and migration among subpopulations must increase substantially from current levels to meet the conservation target. Alternatively, immigration from a large (Ne⩾500) population in northwestern Russia could support the Fennoscandian metapopulation, but immigration must be substantial (5-10 effective immigrants per generation) and migration among Fennoscandian subpopulations must nevertheless increase.

Amphibians are threatened on a global scale and pollutants may be contributing to population declines, but how chemicals impact on their reproduction is poorly understood. We conducted a life cycle analysis to investigate the impacts of early life exposure to two anti-androgens (exposure until completion of metamorphosis;stage 66): flutamide, (50 µg/L)/linuron (9 and 45 µg/L)) on sexual development and breeding competence in Xenopus tropicalis. Our analyses included: mRNA levels of dmrt1, cyp17, amh, cyp19, foxl2 and ar (tadpoles/metamorphs), gonadal histomorphology (metamorphs/adults), mRNA levels of ar/gr (adult male brain/gonad/forelimb), testosterone/corticosterone levels (adult males), secondary sexual characteristics (forelimb width/nuptial pad: adult males) and breeding competence (amplexus/fertility: adult males). Compared to controls, feminised sex ratios and increased number of spermatogonia (adults) were observed after exposure to flutamide and the lower linuron concentration. Exposure to the lower linuron concentration also resulted in demasculinisation of secondary sexual characteristics and reduced male fertility. Flutamide exposure resulted in masculinisation of the nuptial pad and elevated mRNA levels of dmrt1, cyp17, amh and foxl2 in brains (metamorphs). Testosterone levels were higher in all treatment groups, however, overall few effects were observed in response to the higher linuron concentration. Our findings advance understanding of reproductive biology of X. tropicalis and illustrate negative effects of linuron on reproductive processes at a concentration measured in freshwater environments.

Evaluation of shellfish aquaculture for potential contaminants is essential for consumer confidence and safety. Every three years, between 1999 and 2014, bivalve shellfish from aquaculture zones in up to 31 estuaries across 2,000 km of Australia's east coast were tested for cadmium, copper, lead, mercury, selenium and zinc. Inorganic arsenic was included in the analyses in 2002, and total arsenic was used as a screen for the inorganic form in subsequent years. Concentrations of inorganic arsenic, cadmium, lead and mercury were low and did not exceed maximum limits mandated in the Australia New Zealand Food Standards Code. As maximum limits have not been assigned to copper, selenium and zinc, accepted international dietary guidelines were used as a benchmark. Dietary exposure assessments for these elements demonstrated that shellfish from the aquaculture areas investigated do not present a food safety risk. Continued surveillance is essential, given increasing pressure on Australia's coastal resources.