Wallago attu (Freshwater shark) culture in pond: Prospects for farming in Manipur

Abstract

Wallago attu (locally known as Sareng) is a highly valued culinary delicacy in Manipur, northeast India. In view of its cultural and economic relevance, this study focused on developing culture techniques and seed production protocols to support farming of this vulnerable species. Broodstock were raised in ponds (0.2–0.5 ha) at Laphupat Tera, Imphal, using wild-caught juveniles. To promote maturation, the brooders were fed with live carps and tilapia spawn and fry, achieving maturity within just over a year. Induced breeding of selected broodfish (average 5080 g for females and 1024 g for males) was successfully conducted using a synthetic hormone combination (sGnRH analogue + Domperidone) at dosages of 0.8 ml/kg for females and 0.4 ml/kg for males, which triggered spawning within 6–8 h. Fertilized eggs (1.8 ± 0.2 mm) hatched within 18–24 h at 26.2–26.8°C. Nursery rearing of the cannibalistic larvae, were fed with live zooplankton and carp spawn, resulted in fry attaining lengths of 3.8–5.42 cm and weights of 2.0–2.8 g within 15 days,
with 65–70% survival. Grow-out trials in ponds (0.02–0.75 ha) showed that stocking 20-day-old fingerlings (100–120 mm) at 2000–3000/ha, with regular size segregation and feeding of live fish, allowed marketable harvest within 5 months. The findings highlight that periodic segregation of fry and fingerlings is essential to reduce cannibalism and ensure successful culture of this commercially
important species, contributing to both aquaculture development and conservation.