caa a22 4500 606230386 CHVBK 20210128101214.0 cr unu---uuuuu 210128e20151001xx s 000 0 eng 10.1007/s10695-015-0073-6 doi (NATIONALLICENCE)springer-10.1007/s10695-015-0073-6 Digestive system development and study of acid and alkaline protease digestive capacities using biochemical and molecular approaches in totoaba ( Totoaba macdonaldi ) larvae [Elektronische Daten] [Mario Galaviz, Lus López, Alejandra García Gasca, Carlos Álvarez González, Conal True, Enric Gisbert] The present study aimed to describe and understand the development of the digestive system in totoaba (Totoaba macdonaldi) larvae from hatching to 40days post-hatch (dph) from morphological and functional perspectives. At hatch, the digestive system of totoaba was undifferentiated. The anus and the mouth opened at 4 and 5dph, respectively. During exogenous feeding, development of the esophagus, pancreas, liver and intestine was observed with a complete differentiation of all digestive organs. Expression and activity of trypsin and chymotrypsin were observed as early as at 1dph, and increments in their expression and activity coincided with changes in food items (live and compound diets) and morpho-physiological development of the accessory digestive glands. In contrast, pepsin was detected later during development, which includes the appearance of the gastric glands between 24 and 28dph. One peak in gene expression was detected at 16dph, few days before the initial development of the stomach at 20dph. A second peak of pepsin expression was detected at day 35, followed by a peak of activity at day 40, coinciding with the change from live to artificial food. Totoaba larvae showed a fully morphologically developed digestive system between 24 and 28dph, as demonstrated by histological observations. However, gene expression and activity of alkaline and acid proteases were detected earlier, indicating the functionality of the exocrine pancreas and stomach before the complete morphological development of the digestive organs. These results showed that integrative studies are needed to fully understand the development of the digestive system from a morphological and functional point of views, since the histological organization of digestive structures does not reflect their real functionality. These results indicate that the digestive system of totoaba develops rapidly during the first days post-hatch, especially for alkaline proteases, and the stomach becomes functional between 20 and 24dph allowing the weaning process to begin at this age. Springer Science+Business Media Dordrecht, 2015 Fish larvae nationallicence Totoaba macdonaldi nationallicence Digestive system nationallicence Ontogeny nationallicence Proteases nationallicence Gene expression nationallicence Galaviz Mario Facultad de Ciencias Marinas, Universidad Autónoma de Baja California (UABC), PO Box 76, 22860, Ensenada, BC, Mexico aut López Lus Facultad de Ciencias Marinas, Universidad Autónoma de Baja California (UABC), PO Box 76, 22860, Ensenada, BC, Mexico aut García Gasca Alejandra Centro de Investigación en Alimentación y Desarrollo, Unidad Mazatlán en Acuicultura y Manejo Ambiental, Avenida Sábalo Cerritos s/n, 82010, Mazatlán, Sinaloa, Mexico aut Álvarez González Carlos Laboratorio de Acuicultura Tropical DACBIOL-UJAT, Carr. Villahermosa-Cárdenas Km 0.5, Bosques de Saloya, Villahermosa, Tabasco, Mexico aut True Conal Facultad de Ciencias Marinas, Universidad Autónoma de Baja California (UABC), PO Box 76, 22860, Ensenada, BC, Mexico aut Gisbert Enric Institut de Recerca i Tecnologia Agroalimentàries. IRTA- Sant Carles de la Ràpita, Crta. Poble Nou km 5.5, 43540, Sant Carles de la Rapita, Spain aut Fish Physiology and Biochemistry Springer Netherlands 41/5(2015-10-01), 1117-1130 0920-1742 41:5<1117 2015 41 10695 https://doi.org/10.1007/s10695-015-0073-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10695-015-0073-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Galaviz Mario Facultad de Ciencias Marinas, Universidad Autónoma de Baja California (UABC), PO Box 76, 22860, Ensenada, BC, Mexico aut NATIONALLICENCE 700 1- López Lus Facultad de Ciencias Marinas, Universidad Autónoma de Baja California (UABC), PO Box 76, 22860, Ensenada, BC, Mexico aut NATIONALLICENCE 700 1- García Gasca Alejandra Centro de Investigación en Alimentación y Desarrollo, Unidad Mazatlán en Acuicultura y Manejo Ambiental, Avenida Sábalo Cerritos s/n, 82010, Mazatlán, Sinaloa, Mexico aut NATIONALLICENCE 700 1- Álvarez González Carlos Laboratorio de Acuicultura Tropical DACBIOL-UJAT, Carr. Villahermosa-Cárdenas Km 0.5, Bosques de Saloya, Villahermosa, Tabasco, Mexico aut NATIONALLICENCE 700 1- True Conal Facultad de Ciencias Marinas, Universidad Autónoma de Baja California (UABC), PO Box 76, 22860, Ensenada, BC, Mexico aut NATIONALLICENCE 700 1- Gisbert Enric Institut de Recerca i Tecnologia Agroalimentàries. IRTA- Sant Carles de la Ràpita, Crta. Poble Nou km 5.5, 43540, Sant Carles de la Rapita, Spain aut NATIONALLICENCE 773 0- Fish Physiology and Biochemistry Springer Netherlands 41/5(2015-10-01), 1117-1130 0920-1742 41:5<1117 2015 41 10695