Variations by sex and body size in the avoidance tests of sodium linear laurylbenzene sulfonate and fenitrothion using a fish, medaka Oryzias latipes.

Abstract

This paper examined variations by sex and body size in the avoidance tests of LAS (sodium linear laurylbenzene sulfonate) and fenitrothion using a fish, adult medaka Oryzias latipes, in a small chamber system with a bisymmetrie parallel-flow. Although these avoidance tests were re-peated many times in different seasons, the reproducibility of the tests was excellent. No significant difference was found in between the male and female of same size. However, the avoidance con-centrations of small medaka were apparently lower than those of large medaka, indicating that avoidance response to the aquatic contaminants may vary significantly with fish body size. There-fore, comparison of avoidance tests among different species of fish should take into consideration the fish size.