Effect of the first feeding on somatic growth and development of the alimentary tract of the pejerrey bonaerense (Odontesthes bonariensis)

FAGGIANI, M; RIO, DANIELA M.; PÉREZ-SIRKIN, DANIELA I.; BERIOTTO, AGUSTINA C.; SIMÓ, IGNACIO; DI YORIO, MARÍA P.; SALLEMI, JULIETA E.; BRECCIA, ANDRÉS; ARRANZ, SILVIA E.; VISSIO, PAULA G.

Mar del Plata

Congreso; Reunión conjunta SAIC SAB AAFE AACYTAL 2023. XXV Jornadas Anuales de la Sociedad Argentina de Biología (SAB).; 2023

SAIC SAB AAFE AACYTAL

The pejerrey bonaerense is a highly valued fish in Argentina for the quality of its meat and its importance in sport fishing; however, its culture is under development, presenting low larval growth and survivalrates. Considering that the initial feeding is a determining factor for the animals´ survival and development and that feeding protocols for the early life stages of this species have not yet been established, the aim of this study is to evaluate the possible effects of different initial diets on the larval development and the maturation of the alimentary tract of the pejerrey bonaerense. From hatching to 40days post-hatching (dph), animals were fed daily until satiation with unenriched 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 in each tank until the end of the experiment. The degree of enrichment of the Artemia in fatty acid was assessed by GC/MS, the survivaland growth of the fish were evaluated at 90 dph, and the development of their alimentary tracts was studied by histological sections at 9 dph, focusing on the number of taste buds, the width and heightof the intestinal folds and the area of hepatocytes. The enriched Artemia showed an increase in their content of ω3 fatty acids. No significant differences were obtained in the survival of the pejerrey,while a tendency to a higher weight gain was observed in animals of treatment M (0.47 ± 0.05 g vs. S: 0.33 ± 0.03 g, P: 0.39 ± 0.03 g). Histological analysis showed a trend towards a difference in thenumber of taste buds between treatments and a significant increase in 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 obtained provide additional knowledge for improving the larval culture of the pejerrey bonaerense.