Somatic growth and RNA/DNA rate of Eucinostomus argenteus (Pisces: Gerreidae) juveniles stages at two localities of the Venezuelan Caribbean.

Con la finalidad de evaluar la asociación de índices de crecimiento en estadios tempranos de peces marinos, se estimó la tasa de crecimiento somático y las condiciones fisiológicas de Eucinostomus argenteus en dos zonas del nor-oriente venezolano: Bahía de Mochima y Golfo de Cariaco. La edad y el crecimiento fueron estimados basados en análisis de otolitos sagitta. Las condiciones fisiológicas fueron evaluadas por medio de las concentraciones de proteínas y la relación ARN/ADN, empleando técnicas espectofotométricas y fluorométricas sobre tejido muscular. Las relaciones entre tallas con la edad y el diámetro de los otolitos resultaron positivas, significativas y ajustadas a un modelo de regresión lineal. Los valores de la tasa de crecimiento reciente oscilaron entre 0.178 y 0.418mm día-1, la tasa de crecimiento retrocalculado varió entre 0.295 y 0.393mm día-1, y la tasa ARN/ADN osciló entre 1.65 y 6.97. No se registraron diferencias entre las zonas de estudio, sin embargo se reportaron diferencias entre localidades. A pesar de no encontrarse correlación entre la tasa de crecimiento y la relación ARN/ADN, los valores reportados sugieren crecimiento positivo de los individuos silvestres en las localidades evaluadas. No obstante, ciertas localidades mostraron valores que indican pobres condiciones nutricionales, pudiendo afectarse a futuro otras tasas vitales.In order to evaluate the association among growth indices of marine fishes at early life stages, the somatic growth rate and physiological conditions of Eucinostomus argenteus were estimated at two Venezuelan North-East zones: Mochima Bay and Cariaco Gulf. The age and somatic growth rate were estimated based on daily growth increments in sagitta otoliths. The physiological conditions were evaluated with proteins concentrations and RNA/DNA rate, which were estimated by spectrofluorometric and fluorometric techniques, respectively, on muscle tissue. Juvenile standard length ranged from 9.80 to 39.20mm from 21 to 73 days of age. At all the study localities there were significant and positive correlations between age, otolith diameter and body size, and fitted to a linear regression model. The values of recent growth rate ranged from 0.178 to 0.418mm day-1, backcalculated growth rate oscillated between 0.295 - 0.393mm day-1, and RNA/DNA rate ranged from 1.65 to 6.97. Differences were not found between study zones, but there were differences between localities. Despite the fact that there was no correlation between juvenile´s somatic growth and RNA/DNA rates, the reported values suggesting a E. argenteus juvenile’s positive growth in their natural habitat at localities studied. Nevertheless, in some localities values that indicate poor nutritional conditions were registered, which could affect other future demographic rates as survivor and fecundit