THE FIRST SPAWNING SUCCESS OF TAPAH (Wallago leerii) FISH IN KAMPAR RIAU

Tapah fish  (Wallago leerii) is a local fish which  inhabits  the river at Kampar regency of Riau. The existence of tapah fish in the open waters  decrease, because of  overfishing,  and consumer high demand . The tapah fish has  high economic value with the price 120.000, -IDR per kg.  The tapah fish culture has been conducted by fish farmer at Kampar regency through the  use of fish seed caught from the wild.  Efforts of domestication for  mass production of tapah fish seed has been initiated through the collaboration research between the Institute for Freshwater Aquaculture Research and Development, at Bogor, West Java  with Central Fish Breeding (CFB), Sei Tibun, Kampar,  Technical implementing Unit  of Fisheries and Marines Services, Riau Povince.   Artificial provagation  has successfully performed for the first time using the broodstocks which have been collected over three years at CFB, Sei Tibun, Kampar

The weight of the three broodstocks which were used  ranged   from 3.0 to 3.5 kg for female and the male ranged from  1.5 -2.5 kg.  The Tapah broodstocks were  injected with the hormone gonadotropin. After 17 hours, the female was stripped , then the eggs were  fertilized with sperm  (dry fertilization).  The results showed that from the three females injected, two  females were successfully ovulation,  and one  female was partial ovulation. The egg diameter ranged from 1.8 to 2.0 mm, with the weight of 7.8 mg for each egg, the fecundity ranged from 3600-8100 eggs / kg. The sperm had  white milk colour, and it was obtained 2-4 ml per male. The eggs  sank and the previtelin expanded to 1.5 times from the initial diameter after 3 hours incubation. Fertilization rate was 60-85%, and the hatching rate was  65%. The eggs hatched after 29 hours on the water temperature 27-29^oC . The newly hatched larvae length was  5.7 mm, and the larvae started eating  at the age of 68 hours after hatching, the larvae had  highly cannibalism,  the survival rate at 20 days of age was 25-36%.  The larva had fast growth and  at the 40 days age,  they reached 2-6 g, and the length ranged  from 4-12 cm.  A basic information of bioreproduction can be used as a reference in the future  propagation system.