Recombinant bovine growth hormone identification and the kinetic of elimination in rainbow trout treated by LC-MS/MS.

ABSTRACT

The efficiency of the administration of recombinant bovine growth hormone (rbGH) to enhance fish growth has been widely reported in the literature. Although its use is probable and has been described in several countries, rbGH is prohibited in the European Union (Council Decisions 1994/936/EC, 1999/879/EC). In this context, an analytical strategy was optimised in order to identify rbGH-treated fish. Currently, one of the most difficult challenges for the detection of rbGH in fish is probably the choice of the matrix and the corresponding available quantity for analysis. Therefore, based on a previous efficient protocol developed for mammalian species, a method was adapted for very limited serum volume (50 µl) and was successfully implemented to analyse serum collected from seven trout treated with rbGH. The detection of rbGH was possible from the very first day after administration and the hormone could easily be identified at least for 1 month with levels in the range 5-10 µg ml(-1). The limits of detection (LODs) estimated around 0.5 µg ml(-1) rbGH in fish serum are far below observed concentrations in incurred samples and therefore attest to the relevance of the developed protocol.