EFFECT OF THE FIRST FEEDING ON SOMATIC GROWTH AND DEVELOPMENT OF THE ALIMENTARY TRACT OF THE PEJERREY BONAERENSE (ODONTESTHES BONARIENSIS)

FAGGIANI, MARIANO; RIO DANIELA; PEREZ SIRKIN, DANIELA; BERIOTTO, AGUSTINA C; SIMO, I; DI YORIO, MARÍA P.; SALLEMI JULIETA; BRECCIA, ANDRÉS; ARRANZ,SE; VISSIO, PAULA G.

Mar del Plata

Congreso; REUNIÓN ANUAL DE LAS SOCIEDADES DE BIOCIENCIAS; 2023

Sociedad Argentina de Biología

The pejerrey bonaerense is a highly valued fish in Argentina for thequality of its meat and its importance in sport fishing; however, itsculture is under development, presenting low larval growth and survivalrates. Considering that the initial feeding is a determining factorfor the animals´ survival and development and that feeding protocolsfor the early life stages of this species have not yet been established,the aim of this study is to evaluate the possible effects ofdifferent initial diets on the larval development and the maturation ofthe alimentary tract of the pejerrey bonaerense. From hatching to 40days post-hatching (dph), animals were fed daily until satiation withunenriched Artemia nauplii (S), Artemia nauplii enriched with fish oil(P), or Artemia nauplii enriched with a mixture of fish and vegetableoil (M). The live food was then replaced by commercial dry feed ineach tank until the end of the experiment. The degree of enrichmentof the Artemia in fatty acid was assessed by GC/MS, the survivaland growth of the fish were evaluated at 90 dph, and the developmentof their alimentary tracts was studied by histological sectionsat 9 dph, focusing on the number of taste buds, the width and heightof the intestinal folds and the area of hepatocytes.The enrichedArtemia showed an increase in their content of ω3 fatty acids. Nosignificant differences were obtained in the survival of the pejerrey,while a tendency to a higher weight gain was observed in animalsof treatment M (0.47 ± 0.05 g vs. S: 0.33 ± 0.03 g, P: 0.39 ± 0.03g). Histological analysis showed a trend towards a difference in thenumber of taste buds between treatments and a significant increasein the area of hepatocytes in individuals of treatment M (135.73 ±10.92 μm2 vs. P: 101.32 ± 6.21 μm2), suggesting a greater energyreserve at the beginning of their development. The results obtainedprovide additional knowledge for improving the larval culture of the pejerrey bonaerense.