Prawn - Digestive System

The fresh water prawn, Palaemon malcolmsonii, belongs to the phylum Arthropoda, Class Crustacea, is widely found in fresh water ponds, lakes, streams in India. It is omnivorous, feeding on algae, mosses, certain weeds, small insects, snails, tadpoles and small fishes. It is nocturnal, come out in search of food during night and take rest during day time in the hidden places under water.
The Digestive system of prawn can be studied under two heads viz., Structural aspect and Functional aspect.
In the structural aspect, Alimentary canal, its parts and Digestive glands are discussed. Functional aspect is discussed under five steps viz., Ingestion, Digestion, Absorption, Assimilation and Egestion.
Prawn consists only one digestive gland called 'Hepatopancreas', which can be considered as combination of Liver, Pancreas and Small Intestine.