Long depletion time of enrofloxacin in rainbow trout (Oncorhynchus mykiss).

The international production of farmed fish has been growing continuously over recent years. Until now few veterinary drugs have been approved by the European Union for use in aquaculture, and this has favored the off-label use of products authorized for use in food-producing animal species different from fishes among fish farmers. Adequate field studies are lacking, especially for those species called minor species which are consumed extensively only in some European countries.

Some considerations on the kinetics of pathogenic prions formation.

Literature data, respective to kinetics of infectivities due to prion diseases, have been here reconsidered. The autocatalytic phenomenon of prion replication and the process of advancement of the infection are also considered. A model describing the interconversion from "normal" into "pathogenic" prions, and the subsequent growth of the infection, is proposed.