Earthworm (Perionyx excavatus) as a main protein source for growing zig-zag eel (Mastacembelus armatus) in small-household, aquaculture-based farming systems in the Mekong river delta, Vietnam

Phan Phuong Loan, Nguyen Huu Yen Nhi, Tran Thi Thanh Van and Tran Phong Phu

An Giang University, Vietnam
pploan@agu.edu.vn

Abstract

The purpose of the present study was to show: (i)  that Zig-zag eels can live and grow well in captive culture in artificial conditions such as huge plastic containers; and (ii) that earthworms produced from live stock manure can be a good protein source and can replace the natural feed sources for growing zig-zag eels in artificial culture. Perionyx excavatus were cultured on fresh cow manure in three wooden boxes, which were surrounded by plastic sheets. The area of each frame was 2 x 2 x 0.4m. Earthworm seed was put into the wooden boxes with density of 2 kg per m² . Biomass production of earthworms was determined after 60 days and yielded 3.5kg adult earthworm/m².  Temperature, pH and DO were within the normal range for fish culture.  Growing Zig-zag eels were fed small shrimps as a control treatment (SS), or earthworms (EW) or commercial pellet feed (CP). Daily weight gain (DWG), specific growth rate (SGR), and survival rate (SR) were measured. Growth rate of the Zig-zag eels was best for EW, followed by SS with the poorest performance on CP. There was no effect of feed source on  fish survival rate. It was concluded that earthworms are a valuable source of protein for growing Zig-zag eels.

Keywords: Captive culture, cattle manure, commercial feed, fish, recycling