IADO   05364
INSTITUTO ARGENTINO DE OCEANOGRAFIA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Metabolic responses to trophic habits of Ramnogaster arcuata
Autor/es:
MOLINA , J. M.; BLASINA, G.E.; LOPEZ CAZORLA, A.; RONDA, A. C
Lugar:
Mar del Plata
Reunión:
Congreso; XVIII Congreso Latinoamericano de Ciencias del Mar-COLACMAR 2019 Asociación Latinoamericana de Investigadores en Ciencias del Mar-ALICMAR; 2019
Institución organizadora:
Universidad Nacional de Mar del Plata Facultad de Ciencias Exactas y Naturales
Resumen:
Biological responses of the coastal fish Ramnogaster arcuata in relation with its trophic habits were evaluated in aquatic ecosystems in which the species is widespread. To cover estuarial and coastal environments where the specie inhabiting, two sites were selected in the Bahía Blanca estuary (BBE) and two in the adjacent coastal zone (ACZ). Only fish between 1 and 2 years old, according to its total length, were analyzed. Fulton´s condition index (K) and diet composition of R. arcuata was asses. Lipid peroxidation, determinates through the thiobarbituric acid reactive substances (TBARs), protein content, and activities of the metabolic enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined in liver of fish. Only correlation analyses between assessed parameters which presented variation among sites were performed. A total of 142 R. arcuata were caught in the BBE and 35 in the ACZ. The main differences recorded between BBE and ACZ concerns condition index, trophic ecology (including feeding activity and diet composition) and liver metabolic biomolecules (ALT/AST enzymes and TBARS). Consume on mysids was positively correlated with ALT and negatively with TBARs; while the ostracods consume showed a negative correlation with ALT. Activities of ALT and AST correlated with each other positively, indicating that if one of these enzymes is activated or inhibited, the other one follows the same pattern. Moreover, ALT/AST activities positively correlated with K while a negative correlation between K and TBARs is apparent (Figure). According to results presented here, a biological response, both in the body condition and the enzyme activity, is closely linked to the diet composition was observed. The main prey items of R. arcuata were mesozooplancton. Recent data analysis revealed a strong dependence of the mesozooplankton composition and abundance on the seasonal cycle and degree of habitat deterioration (Berazategui et al., 2018). Modifications in prey composition in the environment could be, finally, affect the general status of fish which ultimately could have impacts on its fitness.