Resumo

TAVARES, R; LEMUS, M  e  CHUNG, KS. Evaluation of the instantaneous growth of juvenile smooth dogfish sharks (Mustelus canis) in their natural habitat, based on the RNA/DNA ratio. Cienc. mar [online]. 2006, vol.32, n.2, pp.297-302. ISSN 0185-3880.

The RNA/DNA and protein/DNA ratios were evaluated to determine the physiological condition of the smooth dogfish shark (Mustelus canis) in its natural habitat. The samples were collected from animals captured by the Venezuelan trawling fleet operating between the north coast of Sucre State and Margarita Island. Proteins (Bradford method) and nucleic acids (fluorometric method) were quantified from muscle tissue samples. Instantaneous growth was estimated from the RNA/DNA and protein/DNA relationships. A decrease in the RNA/DNA ratio was observed in relation to body length in both sexes. In the case of the protein/DNA ratio, the distribution values do not show any tendency relative to body length or sex. The results show that the RNA/DNA ratio can be used to analyze the instantaneous growth and population health of sharks.

Palavras-chave : shark; Mustelus; RNA; DNA; proteins; growth; Venezuela.