The gill sialic acid content as an index of environmental stress in rainbow trout, Salmo gairdneri, Richardson

Abstract
The gill sialic acid content in Rainbow Trout exposed to several aqueous concentrations of ammonia NH3 and/or to a high environmental pH was determined by two different methods. The results showed Warren's method was adequate for the biological material, even without purification of the extracts by Dowex 2.8 resin. A significant increase of the sialic acid concentration occurred in fish exposed to ammonia.