Publication Abstract

Sub-lethal effects of the pesticideDiazinon on olfactory function in mature male Atlantic salmon (Salmo salar L.)parr

A. Moore and C.P. Waring

Diazinon,an organophosphate pesticide, had a sublethal effect on the olfactory system of maturemale Atlantic salmon part. The olfactory responses of the part to prostaglandin F_2α(PGF_2α) were studied after exposure of the epithelium to differentconcentrations of Diazinon in water. Electrophysiological recordings from the epitheliumindicated that the responses to this prostaglandin were significantly reduced at nominalconcentrations as low as 1-0 µg l^-1 and the threshold of detection was reduced10-fold at 2-0 µg l^-1. Mature male salmon parr exposed for a period of 120 hto Diazinon (nominal concentrations 0-3, 0-8, 1-7, 2-7, 5-6, 13, 28 and 45 µg l^-1)also had significantly reduced levels of the reproductive steroids, 17,20βdihydroxy-4-pregnen-3-one,testosterone and gonadotrophin 11 in the blood plasma after priming with ovulated femalesalmon urine. Both prostaglandin F_2α and ovulated female urine are known tohave important roles in synchronizing reproductive physiology and behaviour in salmonidsas well as other fish species. The results are therefore discussed in relation to thepossible sublethal effects of Diazinon on reproduction in the Atlantic salmon and possibleeffects on populations of salmonids.

Reference:

A. Moore and C.P. Waring, 1995. Sub-lethal effects of the pesticide Diazinon on olfactoryfunction in mature male Atlantic salmon (Salmo salar L.) parr. Journal of Fish Biology,48: 758-775.