Enzymatic Digestion Of Stomachless Fish Zenarchopterus Buffonis

Abstract

The absence of a stomach in halfbeaks (Hemiramphidae) does not restrain their capability in digesting food item. Halfbeak (Zenarchopterus buffonis) is known to have a wide spectrum of dietary preference. The present study investigates the activity of four digestive enzymes along the gut of halfbeaks to determine how they digest their diets as opportunistic omnivores. A total of 20 halfbeak samples were collected from the coastal waters of Peninsular Malaysia. Overall, we found that the α- amylase shows the highest enzymatic activity, followed by lipase and relatively low activity of protease (trypsin and aminopeptidase) along the alimentary canal, even though all of the enzymes show no significant difference among the gut sections. The increasing activity of α-amylase from proximal to distal intestine but with a notably drop-off in rectum zone demonstrates its high consumptions on arthropods and plant materials which are available in the environment. Presence of lipase with uniform distribution along the gut is expected due to insectivorous nature of fish, which gives an indication that there is possibility for halfbeaks to assimilate a wider array of diet nutrients. Our findings in this study is thought to be beneficial for improving knowledge on the biology and nutrition physiology of examined species and may provide valuable information on current model of stomachless digestive system, yet further refinement may be necessary.