Ontogeny of digestive enzymes in larvae of the Clown Anemonefish, Amphiprion ocellaris

Introduction: The Clown anemonefish (Amphiprion ocellaris) is the most popular fish species in the marine aquarium trade; however, there is a lack of information on their digestive physiology during larval ontogeny, valuable information needed for diet design and management protocols. Objective: To characterize the early digestive enzymes of A. ocellaris larvae. Methods: We used three pools (10 larvae each) and extracted 10 samples per tank, from just before hatching to the 38th day. We analyzed the specific activity of acid and alkaline proteases, trypsin, chymotrypsin, leucine aminopeptidase and lipase; and did acid and alkaline protease zymograms. Results: We detected all measured enzymes at hatching. Acid proteases increased in activity until the 38th day. Alkaline proteases, trypsin, chymotrypsin, and leucine aminopeptidase had the same pattern, and maximum activity on the 8th day, decreasing at the 38th day. Lipase activity peaked on the 8th and 30th day. The acid zymogram had a single band, appearing on the 8th day. A total of eight alkaline proteases were revealed (154.2, 128.1, 104.0, 59.8, 53.5, 41.9, 36.5 and 25.1 KDa), with seven bands on the 1st day and all bands from the 3rd to 8th day, decreasing at two bands (41.9 and 25.1 KDa) in the 38th day. Conclusion: A. oceuaris has a functional stomach on the 8th day, and, on the 38th day, a digestive omnivore pattern with a tendency to carnivory. Key words: digestive development; early ontogeny; electrophoresis; larvae; lipases; proteases. Introduccion: El pez payaso (Amphiprion oceuaris) es la especie de pez mas popular en el comercio de acuarios marinos; sin embargo, falta informacion sobre su fisiologia digestiva durante la ontogenia larval, informacion valiosa necesaria para protocolos de diseno y manejo dietetico. Objetivo: Caracterizar las enzimas digestivas tempranas de larvas de A. oceuaris. Metodos: Usamos tres homogenados (con 10 larvas cada uno) y extrajimos 10 muestras por tanque, justo antes de la eclosion hasta el dia 38. Analizamos la actividad especifica de proteasas acidas y alcalinas, tripsina, quimotripsina, leucina aminopeptidasa y lipasa; e hicimos zimogramas de proteasas acidas y alcalinas. Resultados: Detectamos todas las enzimas medidas en la eclosion. La actividad de proteasas acidas incremento hasta el dia 38. Proteasas alcalinas, tripsina, quimotripsina, y leucina aminopeptidasa tuvieron el mismo patron, con actividad maxima en el octavo dia, decreciendo en el dia 38. Hubo