Abstract:
The Sri Lankan Stinging catfish (Heteropneustes fossillis) or Hunga is one of the most
popular underutilized, cannibalistic, highly nutritious indigenous species. Due to
the inadequacy of information on reproduction, breeding and larval rearing,
Stinging Catfish has not introduced to the Sri Lankan aquaculture industry yet.
Therefore, this research is focused to examine the possibility of induced breeding
using GnRh and larval rearing of Stinging Catfish with phytogenic feed additives to
develop the culture practice. Four matured (2 males and 2 females) fish were
selected as brooders and females were artificially induced using GnRh (0.5 ml/kg
for female) and sperms were obtained by crushed testis. The fertilized eggs hatched
out within 24-28 hrs. After yolk sac absorption, live feeds (Artemia and Daphnia)
were given for 4 days as feed for larvae. Then the larvae were fed with 3 formulated
diets namely T1 (Moringa–Moringa oleifera added), T2 (Mukunuwenna–
Alternanthera sessilis added) and T3 (the control) at two hour intervals throughout
the day for three weeks. Specific growth rate, weight gain and survival rate were
significantly higher (<0.05) in larvae fed phytogenic additives added formulated
diets (T1 and T2) compared to Control treatment. The rate of survival, specific
growth rate, and weight gain for T1, T2 and T3 were, 89.267%, 89.467%, 63.800%,
3.88%, 3.76%, 3.46%, and 260 mg, 250 mg, 163.43 mg respectively. Cannibalistic
fish need nutritionally balanced food in bulk quantity during their early larval
stages for uniform growth in the population. In conclusion, the GnRh can be
successfully employed for induced breeding of Stinging Catfish fish and frequent
feeding of Moringa added formulated feed found to be suitable for enhancing
growth as well as minimizing cannibalism.
