Using measurements of muscle cell nuclear RNA with flow cytometry to improve assessment of larval condition of Walleye Pollock (Gadus chalcogrammus)

Nuclear RNA and DNA in muscle cell nuclei of laboratory-reared larvae of Walleye Pollock (Gadus chalcogrammus) were simultaneously measured through the use of flow cytometry for cell-cycle analysis during 2009–11. The addition of nuclear RNA as a covariate increased by 4% the classification accuracy of a discriminant analysis model that used cell-cycle, temperature, and standard length to measure larval condition, compared with a model without it. The greatest improvement, a 7% increase in accuracy, was observed for small larvae (<6.00 mm). Nuclear RNA content varied with rearing temperature, increasing as temperature decreased. There was a loss of DNA when larvae were frozen and thawed because the percentage of cells in the DNA synthesis cell-cycle phase decreased, but DNA content was stable during storage of frozen tissue.

Nuclear and mitochondrial DNA markers for specific identification of istiophorid and xiphiid billfishes

Independent molecular markers based on mitochondrial and nuclear DNA were developed to provide positive identification of istiophorid and xiphiid billfishes (marlins, spearfishes, sailfish, and swordfish). Both classes of markers were based on amplification of short segments (<1.7 kb) of DNA by the polymerase chain reaction and subsequent digestion with informative restriction endonucleases. Candidate markers were evaluated for their ability to discriminate among the different species and the level of intraspecific variation they exhibited. The selected markers require no more than two restriction digestions to allow unambiguous identification, although it was not possible to distinguish between white marlin and striped marlin with any of the genetic characters screened in our study. Individuals collected from throughout each species’ range were surveyed with the selected markers demonstrating low levels of intraspecific character variation within species. The resulting keys provide two independent means for the forensic identification of fillets and for specific identification of early life history stages.

Weather index insurance: Lessons learned and best practices for Bangladesh

WorldFish and the International Centre for Climate Change and Development (ICCCAD) held a two-day workshop on the topic of Weather Index-Based Insurance: Lessons Learned and Best Practices for Bangladesh. Weather index insurance is based on a predefined weather event which when triggered ensures automatic payout to farmers who have taken out insurance. For example, the climatic trigger could be a predefined consecutive number of days where rainfall is below a set level or when the floodwater level reaches above a certain point. Index insurance has been operating for about 10 years in many countries but is still at an early stage in Bangladesh, where there are two schemes currently being piloted and three other projects being developed. The aim of the two-day workshop was twofold: to ascertain the present state of index insurance in Bangladesh and elsewhere, and to work together to identify ways forward.