Enzymatic Activity in the Gastrointestinal Tract of Pimelodus maculatus (Teleostei, Siluriformes) in Two Neotropical Reservoirs with Different Trophic Conditions



Document title: Enzymatic Activity in the Gastrointestinal Tract of Pimelodus maculatus (Teleostei, Siluriformes) in Two Neotropical Reservoirs with Different Trophic Conditions
Journal: Brazilian archives of biology and technology
Database: PERIÓDICA
System number: 000387743
ISSN: 1516-8913
Authors: 1
1
1
Institutions: 1Universidade Federal Rural do Rio de Janeiro, Laboratorio de Ecologia de Peixes, Seropedica, Rio de Janeiro. Brasil
Year:
Season: Jul-Ago
Volumen: 58
Number: 4
Pages: 605-612
Country: Brasil
Language: Inglés
Document type: Artículo
Approach: Experimental, aplicado
English abstract Enzymatic activities for digestion of proteins and carbohydrates were compared among three organs of the digestive system of Pimelodus maculatus in two reservoirs with different trophic conditions during the winter of 2006. The aim was to test the hypothesis that enzymatic activity for the digestion of proteins and carbohydrates differed among organs and that such activities differ between the trophic state of the environment. Enzymatic activities were determined through the assays of specificity for trypsin, chymotrypsin and β-glucosidase enzymes. The intestine had higher trypsin-like enzymatic activities compared to the stomach and liver. The highest β-glucosidase activity was found in the liver compared to the stomach and intestine in the oligotrophic reservoir only. Overall, enzymatic activity did not differ between the eutrophic and oligotrophic reservoirs, although the intestinal chymotrypsin was comparatively higher in the eutrophic reservoir and the hepatic β-glucosidase was higher in the oligotrophic reservoir. These findings indicated that most digestive activity occurred in the intestine for P. maculatus, which was probably related to its omnivorous/carnivorous feeding habits. The highest proteolytic activity in the intestine was expected for most fishes, but the high hepatic β-glucosidase in the oligotrophic reservoir was unexpected. The hepatic β-glucosidase as well as the intestinal chymotrypsin-like activity could be considered as the candidates for biomarkers of environmental quality
Disciplines: Biología
Keyword: Fisiología animal,
Peces,
Peces de agua dulce,
Tracto digestivo,
Enzimas,
Hábitos alimenticios,
Pimelodus maculatus,
Siluriformes
Keyword: Biology,
Animal physiology,
Fish,
Freshwater fish,
Digestive tract,
Enzymes,
Feeding habits,
Pimelodus maculatus,
Siluriformes
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