Changes in gill and hepatic nucleolar activity of the neotropical silverside Odontesthes bonariensis (Pisces: Atherinidae) in response to feeding levels

CARRIQUIRIBORDE P.; DULOUT F.N.; DE LUCA J.C.; RONCO A. E.

Manaos, Brasil

Congreso; VI International Congress on the Biology of Fish; 2004

Physiology Section, American Fisheries Society

The responses of the nucleolar parameters (volume (NV) and number (NN)) were assessed in the gill and liver of Odontesthes bonariensis (Pisces: Atherinidae) exposed to a reduction in the feeding levels during a maximum period of two weeks. NV was very sensitive to changes in the feeding regime of fish, showing an exponential decrease with time and quickly reaching a new equilibrium state according to the new feeding regime. No response was observed in NN. Results support nucleolar size as a sensitive indicator of the physiological condition of the fish that could be useful for aquaculture purposes in countries with scarce resources