Bighead catfish and larvae Bighead catfish of both sexs
(mean weight 80.53.5 g and 4.20.15 g respectively) obtained
from Deparment of Aqutic Science, Burapha University were
acclimated in a 2000 L concrete tank provided with continuous
aeration and a water flowthrough system (flow rate of 500 L h-1
;
27-29 C; pH 7.8-8.2) and oxygen flow 6.5 ppm. Experiments
with larvae Bighead catfish were conducted in static 20 L aquaria
containing 10 L of water. The first series of experiments
examined the effects of eugenol derivatives concentration on the
behaviour and stress of larvae and Bighead catfish. Ten larvae
per sample were individually exposed to either 25, 50 ppm