Body composition of Atlantic salmon (Salmo salar L.) studied by neutron activation analysis.

This paper describes the measurement of whole body Ca, Cl, K, N, Na, O and P in Atlantic salmon parr, adults and kelts by neutron activation analysis (NAA). This technique is based on counting the specific gamma activity in samples which is present naturally or is produced by neutron irradiation. Body composition (fat, mineral, protein and water) are estimated from these data. NAA has advantages over chemical methods with the potential for in vivo measurements. Anthropogenic 137Cs was found in sea-water (SW) salmon but not found in the freshwater (FW) stages (parr and kelts). Presence of this isotope in fish caught in FW indicates recent SW residence.