129 research outputs found

    Do voluntary international environmental agreements work?

    Get PDF
    We consider the effects of international environmental agreements, using the Sofia Protocol on the reduction of nitrogen oxides. Our analysis utilizes panel data from 25 European countries for the period 1980–96. We divide these countries into “participants” and “non-participants”—that is, those that did and those that did not ratify the Sofia Protocol, respectively. Using a difference in difference estimator, we find that signing the treaty has a significant positive impact on emission reduction. The yearly reduction is approximately 2.4 percent greater than it would have been without the Sofia Protocol.international environmental agreements; public goods; evaluation

    Complete Genome Sequences of 12 Quinolone-Resistant Escherichia coli Strains Containing qnrS1 Based on Hybrid Assemblies

    Get PDF
    In total, 12 quinolone-resistant Escherichia coli (QREC) strains containing qnrS1 were submitted to long-read sequencing using a FLO-MIN106 flow cell on a MinION device. The long reads were assembled with short reads (Illumina) and analyzed using the MOB-suite pipeline. Six of these QREC genome sequences were closed after hybrid assembly

    Microbial growth in modified atmosphere packaged blue mussels (Mytilus edulis)

    Get PDF
    Microbial growth was investigated in live blue mussels (Mytilus edulis) packaged in modified atmosphere (MA) and stored at -1 and 4 oC for 19 days. The mortality of mussels was 0.8 % after 19 days of storage with lowest mortality at -1 and in CO2 atmosphere. The increase in bacterial numbers in the mussel flesh was low, 1- 2 log units, measured as Aerobic Plate Counts, H2S-producing bacteria, and psychrotrophic bacteria. There was significant lower bacterial growth (p<0.05) in an atmosphere with CO2:O2 compared air and N2:O2 and at -1 oC. An initial level of < 3 mg Tri-Methylamine Oxid-N (TMAO-N)/ 100g was found in the mussels, detectable levels of trimethylamine-N (TMA) were observed after 11 days of storage and TMA-N increased to 1 – 3 mg/100g in 19 days. Total Volatile Nitrogen (TVN) increased from 3.4 to 18 mg/100g in 19 days and may be an important chemical indicator to be used in defining the shelf life. Low temperature (-1 oC) did not significantly increase the shelf life, but the superchilled temperature will control pathogenic growth. MA packaging of live blue mussels is a promising packaging technology for retail distribution, with a shelf life of 11-12 days based on sensory scores.publishedVersio

    Use of lumpfish for sea-lice control in salmon farming: challenges and opportunities

    Get PDF
    Efficient sea-lice control remains one of the most important challenges for the salmon farming industry. The use of wrasse (Labridae) as cleaner fish offers an alternative to medicines for sea-lice control, but wrasse tend to become inactive in winter. Lumpfish (Cyclopterus lumpus) continue to feed on sea-lice at low temperatures, and commercial production has escalated from thousands of fish in 2010 to well over 30 million juveniles deployed in 2016. However, production still relies on the capture of wild broodstock, which may not be sustainable. To meet global industry needs, lumpfish production needs to increase to reach c. 50 million fish annually and this can only come from aquaculture. We review current production methods and the use of lumpfish in sea cages and identify some of the main challenges and bottlenecks facing lumpfish intensification. Our gap analysis indicates that the areas in most need of research include better control of maturation for year-round production; formulation of appropriate diets; artificial selection of elite lines with desirable traits; and development of vaccines for certified, disease-free juvenile production. The welfare of farmed lumpfish also needs to be better quantified, and more information is needed on optimal densities and tank design. Finally, the risk of farmed lumpfish escaping from net pens needs to be critically assessed, and we argue that it might be beneficial to recover cleaner fish from salmon cages after the production cycle, perhaps using them as broodstock, for export to the Asian food markets or for the production of animal feeds

    Transport of Babesia venatorum-infected Ixodes ricinus to Norway by northward migrating passerine birds

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Bovine babesiosis is regarded as a limited health problem for Norwegian cows, and the incidence has decreased markedly since the 1930s. Rare cases of babesiosis in splenectomised humans from infection with <it>Babesia divergens </it>and <it>B.venatorum </it>have been described. The objective of this study was to determine whether birds can introduce <it>Babesia</it>-infected ticks. There are between 30 and 85 million passerine birds that migrate to Norway every spring.</p> <p>Methods</p> <p>Passerine birds were examined for ticks at four bird observatories along the southern Norwegian coast during the spring migrations of 2003, 2004 and 2005. The presence of <it>Babesia </it>was detected in the nymphs of <it>Ixodes ricinus </it>by real-time PCR. Positive samples were confirmed using PCR, cloning and phylogenetic analyses.</p> <p>Results</p> <p>Of 512 ticks examined, real-time PCR revealed five to be positive (1.0%). Of these, four generated products that indicated the presence of <it>Babesia </it>spp.; each of these were confirmed to be from <it>Babesia venatorum </it>(EU1). Two of the four <it>B. venatorum</it>-positive ticks were caught from birds having an eastern migratory route (<it>P</it>< 0.001).</p> <p>Conclusions</p> <p>Birds transport millions of ticks across the North Sea, the Skagerrak and the Kattegat every year. Thus, even with the low prevalence of <it>Babesia</it>-infected ticks, a substantial number of infected ticks will be transported into Norway each year. Therefore, there is a continuous risk for introduction of new <it>Babesia </it>spp. into areas where <it>I. ricinus </it>can survive.</p

    Evaluation of vaccine delivery systems for inducing long-lived antibody responses to Dermanyssus gallinae antigen in laying hens

    Get PDF
    Dermanyssus gallinae, the poultry red mite, is a global threat to the commercial egg-laying industry. Control of D. gallinae is difficult, with only a limited number of effective pesticides and non-chemical treatments available. Here we characterise the candidate vaccine antigen D. gallinae cathepsin D-1 (Dg-CatD-1) and demonstrate that purified refolded recombinant Dg-Cat-D1 (rDg-CatD-1) is an active aspartyl proteinase which digests haemoglobin with a pH optimum of pH 4. Soluble protein extracts from D. gallinae also have haemoglobinase activity, with a pH optimum comparable to the recombinant protein and both proteinase activities were inhibited by the aspartyl proteinase inhibitor Pepstatin A. Enzyme activity and the ubiquitous localization of Dg-CatD-1 protein in sections of adult female mites is consistent with Dg-CatD-1 being a lysosomal proteinase. Using Dg-CatD-1 as a model vaccine antigen, we compared vaccine delivery methods in laying hens via vaccination with: i) purified rDg-CatD-1 with Montanide™ ISA 71 VG adjuvant; ii) recombinant DNA vaccines for expression of rDg-CatD-1 and iii) transgenic coccidial parasite Eimeria tenella expressing rDg-CatD-1. In two independent trials, only birds vaccinated with rDg-CatD-1 with Montanide™ ISA 71 VG produced a strong and long-lasting serum anti-rDg-Cat-D1 IgY response, which was significantly higher than control birds vaccinated with adjuvant only. Furthermore, we showed that egg laying rates of D. gallinae mites fed on birds vaccinated with rDg-CatD-1 in Montanide™ ISA 71 VG was reduced significantly compared with mites fed on unvaccinated birds

    Draft genome assembly of the poultry red mite, Dermanyssus gallinae

    Get PDF
    The poultry red mite, Dermanyssus gallinae, is a major worldwide concern in the egg-laying industry. Here, we report the first draft genome assembly and gene prediction of Dermanyssus gallinae, based on combined PacBio and MinION long-read de novo sequencing. The ∼959-Mb genome is predicted to encode 14,608 protein-coding genes
    corecore