Effect of alcohol and congeners on aggressive response in Betta splendens
Quarterly Journal of Studies on Alcohol. Supplement, (May 1970)Abstract
Measured the aggressive response of 12 male Siamese fighting fish before and after 6 hr. of immersion in individual tanks containing 1 of 3 test solutions: 285 mg of ethanol/100 ml, commercial bourbon whisky diluted to the same ethanol concentration, and a congener solution diluted to contain amounts of congeners similar to that of the 2nd test solution and containing 10 mg of ethanol/100 ml. Groups were reversed a wk. later so that 12 Ss were tested as both control and test in all 3 conditions. The accumulated time the gill membrane of the S was lowered in response to a 3-min exposure to its mirror image was used as an index of aggressive response. In the ethanol solution the mean accumulated gill show increased by 11.42 sec. (p < .05), in the bourbon and congener solutions the aggressive response decreased by 24.75 (p < .001) and 19.33 sec. (p < .005), respectively. In the congener solution 5 of the 12 Ss showed no aggressive response whereas all the Ss in the bourbon solution showed some residual aggression after the 6-hr immersion. Results suggest that the behavioral effects of congeners and ethanol involve different physiological mechanisms.