PD/A CRSP Aquanews-Summer 2003
New Fish Species Studied for Aquaculture Potential by Aquaculture CRSP Researchers
by Dhirendra Prasad Thakur, Asian Institute of Technology
Editors note: This article is the first in a series on the biology of fish species being studied for aquaculture potential. Future articles will cover the mahseer (Tor putitora) and climbing perch (Anabas testudineus). Thakur worked with the Aquaculture CRSP at the Asian Institute of Technology from 1996 to 1998 and rejoined the team in April 2003 after obtaining his Ph.D. in Japan.
Stinging catfish (Heteropneustes fossilis)
eteropneustes fossilis (Bloch, 1794) is commonly known as the stinging catfish. The name is well earned, taken from its ability to inflict severe, painful wounds with the dorsal spines and to inject a poison produced by glandular cells in the epidermal tissue covering the spines (Nelson, 1994): this is a venomous fish.
The species is a highly-prized air-breathing freshwater fish from the Indian subcontinent and southeast Asian region. The range encompasses India, Thailand, Bangladesh, Pakistan, Nepal, Sri Lanka, Myanmar, Indonesia, and Cambodia (Smith, 1945; Burgess, 1989). Primary habitat includes ponds, ditches, swamps, and marshes. It can tolerate slightly brackish water. The fish adapts well to hypoxic water bodies and to high stocking densities (Dehadrai et al., 1985).
The family Heteropneustidae includes two species, of which H. fossilis is the better known. Heteropneustidae are extremely hardy and are able to withstand severe drought conditions with the aid of accessory breathing organs.
Heteropneustidae have an elongated, subcylindrical body; just beyond the ventral fin bases, the body tapers off to the tail. The head is depressed and bony plates cover the top and sides. The snout is depressed, and the nostrils are far apart; the slit-like anterior nostrils are positioned behind the nasal barbules. There are four pairs of rather long barbels, the maxillary pair extending as far as the ventral fins, and the two pairs of mandibular barbels and the nasal barbules reaching the end of the pectoral fins. The mouth is small and terminal. The eyes are relatively small, lateral in position, and with a free orbital rim. The gill openings are wide and the gill membranes are free from the isthmus. There are seven branchiostegal rays. The gas bladder is enclosed in a bony capsule (Burgess, 1989).
Several stinging catfish in bucket.
Photo by: Abdul Wahab
Heteropneustids possess a pair of long, hollow, cylindrical cavities extending backward on each side of the body from the gill cavity through the muscle of the back. These are accessory breathing organs that serve as primitive lungs enabling the fish to utilize atmospheric oxygen, and thus they are also called lung fish. This appears to be a necessary adaptation to living habitually in oxygen deficient stagnant pools and swamps. They are not able to live completely out of water for many hours but, like the clariids, can cross dry stretches of land in search of better conditions (Burgess, 1989).
Stinging catfish is reported to be highly nutritive, recuperative, and possessing of medicinal properties. This fish is esteemed for its invigorating qualities (Alikunhi, 1957). Its flesh is rich in protein and iron, and fat content is lower in comparison to that in other fishes. This fish is popular particularly because it can be cultivated in swampy areas and derelict water bodies without involving costly reclamation. Unlike water-breathing fish, air-breathing fish can be easily stored and transported live to consumers. Thus, this species is ideal for wastewater aquaculture (Tharakan and Joy, 1996). The maximum-recorded size of stinging catfish is 38 cm (Sinha, 1993).
The fish is heterosexual. Externally, sexes can be accurately distinguished only during breeding when secondary sexual characteristics become prominent. The best morphological character indicative of a good H. fossilis brood female is a well-rounded abdomen, the fullness of which extends posteriorly past the pelvic fins. The males, on the other hand, look lean. In a mature female, the genital papilla remains in the form of a raised prominent structure, round and blunt with a slit-like opening in the middle. In males, it remains in the form of a pointed structure. Sexual maturity is attained at the end of the first year of life.
Stinging catfish breed in confined waters during the rainy season but can breed in ponds, derelict ponds, and ditches when sufficient rainwater accumulates.
Seed for stocking in grow-out ponds can be collected from the wild or can be produced by artificial breeding and rearing the larvae to marketable size. Kohli and Vidyarthi (1990) summarized the biological and embryonic development of H. fossilis. They reported the first time breeding was induced for this fish (in Maharastra, India).
Chatterjee et al. (1991) found a yearly spawning cycle with a single breeding season from July to August. Breeding activity is highly sensitive to water temperature. The optimum temperature for successful breeding is 22ºC (Saxena and Sandhu, 1994).
The mature female lays a sticky cluster of yellowy green eggs in the aquarium substrate. Both parents tend to the clutch, fanning the pit to ensure water circulation around the eggs. Care continues well after the fry emerge. Fecundity varies from 3,000 to 45,000 depending upon the size of the fish (Azadi and Siddique, 1986; Burgess, 1989). A female weighing 100 g produces 8,000 eggs on average. Fertilized eggs are mildly adhesive in nature and are either green or brown in color. The incubation period varies from 18 to 24 hours depending on water temperature (Singh et al., 1982; Roy and Pal, 1986; Alok et al., 1993).
Hatchlings average 2.72 mm in length. Yolk gets completely absorbed by the end of the fourth day, but the larvae commence feeding from the third day. Zooplankton, such as ciliates and rotifers, serve as the choicest food of the larvae at this stage. Aerial respiration apparently commences on the eighth day of development. The larval survival rate is low. Low survival may be due to cannibalism, in which the fish devours its own eggs and fry when there is a lack of food (Sinha, 1993).
Stinging catfish is omnivorous and a bottom feeder but can be trained to accept large cichlid foods from the water surface. Larger adults require large foods such as earthworms and frozen prawns. It has a great liking for gastropods.
H. fossilis is best suited for monoculture but can be cultured in combination with Clarias batrachus or Anabas testudineus. In semi intensive culture, the recommended rate of stocking for H. fossilis is 60,000 fingerlings per hectare (Thakur and Das, 1986). In monoculture the reported production range was 1,642 to 7,300 kg ha-1 in four to 11 months of culture period, the average being 4,510 kg ha-1.
Optimum pH and temperature range for H. fossilis are 6.0 to 8.0 and 21 to 25 C. During summer when water bodies start drying up, the fish buries itself in the soil and aestivates. Many fishes live together in such pits. There can be a number of pits in large ponds. H. fossilis also makes nest holes in the embankment of a pond and lives there in colonies. Such holes are usually about a foot below the water surface in the form of anastomosing tubes having several exits. H. fossilis is best suited for culture in shallow ponds to 1 m depth. In addition to its suitability for culture in derelict waters, it can also be cultured in conventional well managed ponds for high production. To reach marketable size, a period of six months is normally quite sufficient.
Alikunhi, K.H., 1957. Fish culture in India. Farm Bulletin No. 20. Indian Council of Agricultural Research, New Delhi, 144 pp.
Alok, D., T. Krishnan, G.P. Talwar, and L.C. Garg, 1993. Induced spawning of catfish, Heteropneustes fossilis (Bloch), using D-Lys (6) salmon gonadotropin-releasing hormone analog. Aquaculture, 115:159-167.
Azadi, M.A. and M.S. Siddique, 1986. Fecundity of the catfish, Heteropneustes fossilis (Bloch). Bangladesh Journal of Zoology, 14(1): 33-39.
Burgess, W.E., 1989. An atlas of freshwater and marine catfishes-A preliminary survey of the Siluriformes. T.F.H. Publications, Inc., 784 pp.
Chatterjee, P.K., A. Kumar, and N.D.P. Sinha, 1991. Gonadal cycle and ovarian electrolyte behavior in air-breathing teleosts, Channa punctatus (Bloch) and Heteropneustes fossilis (Bloch). J. Freshwater Biol., 3(1):37-43.
Dehadrai, P.V., K.M. Yusuf, and R.K. Das, 1985. Package and practices for increasing production of air breathing fishes. In: Aquaculture Extension Manual, New Series, Information and Extension Division of CIFRI. Indian Council of Agriculture Research, pp. 1-14.
Kohli, M.P.S. and S. Vidyarthi, 1990. Induced breeding, embryonic and larval development in Heteropneustes fossilis (Bloch) in the agro-climatic conditions of Maharastra. J. Indian Fish. Assoc., 20:15-19.
Nelson, J.S., 1994. Fishes of the World, 3. John Wiley and Sons, New York, 600 pp.
Roy, S. and B.C. Pal, 1986. Quantitative and qualitative analysis of spawning behavior of Heteropneustes fossilis (Bloch) in laboratory aquaria. J. Fish Biol., 28(3):247-254.
Saxena, P.K. and R. Sandhu, 1994. Influence of temperature on ovarian recrudescence in the Indian catfish, Heteropneustes fossilis (Bloch). J. Fish Biol., 44(1):168-171.
Singh, I.J., H.N. Singh, and T.P. Singh, 1982. Induction of ovulation in Heteropneustes fossilis-Analysis of sex related differences in the potency of homologous and heterologous pituitary extracts. Proc. Int. Sym. Reprod. Physiol. Fish, 2-6 August 1982, Wageningen, Netherlands, 203 pp.
Sinha, V.R.P., 1993. A Compendium of Aquaculture Technologies for Developing Countries. Oxford and IBH Publishing, New Delhi, India, 115 pp.
Smith, H.M., 1945. The Freshwater Fishes of Siam or Thailand. United States National Museum Bulletin 188, Smithsonian Institute, Washington D.C., 622 pp.
Thakur, N.K. and P. Das, 1986. Synopsis of Biological Data on Singhi Heteropneustes fossilis (Bloch, 1974). Bull. No. 39, April 1986. Central Inland Fisheries Research Institute, Barrackpore, India, 32 pp.
Tharakan, B. and K.P. Joy, 1996. Effects of mammalian gonadotropin-releasing hormone analogue, Pimozide, and the combination on plasma gonadotropin levels in different seasons and induction of ovulation in female catfish. J. Fish Biol., 48:623-632.