Auswirkungen der Wassertemperatur auf die Missbildungshäufigkeit pelagischer Fischembryonen

Malformation rates in embryos of dab, whiting, cod, flounder and plaice have been monitored for several years (1984-2006) in the Southern North Sea. For embryos of all species investigated trends for the fluctuation of malformation rates over the time were registered in the areas showing intermediate prevalences at the beginning of the studies in 1984 and maxima in 1987. Thereafter for all species a decrease of malformation rates was found until 2006 excepting an increase in 1996. A significant negative correlation existed between surface water temperature and prevalences of malformed embryos of dab and other species.

Prevention of infestation by Dermestes maculatus Degeer in east African dried fish by solar treatment

East African sun-dried fish infested by Dermestes maculatus were exposed to tropical sunlight at ambient temperature and analysed for insect mortality and weight losses. Solar treatment for 6 to 8 lo was highly effective for one layer of split sun-dried fish and 100% insect mortality was toted, while pest species were still present in the four layer batch. Weight losses between 1.2% and 10.2% were recorded, the top layer suffering the highest loss. The high surface temperature of 60°C caused fish to become brittle and quality losses occurred. A reduction in length of exposure/temperature is probably a presupposition for application of the method to local conditions.