Striped catfish

Developments in hatchery technology for striped catfish (Pangasianodon hypophthalmus)... 

Key words striped catfish, hatchery, fingerling, fry, spawning. 

Directorate, 2011). This fish species is now known worldwide due to its products being exported to 136 countries and territories in 2010 (De Silva and Phuong, 2011). The striped catfish has become the Princess in Vietnamese aquaculture in recent years (Phuong and Oanh, 2010). One of the key drivers for the fast growth of the striped catfish farming sector is the successes of seed production and associated development of hatchery techniques, including the uptake and successful adoption of the techniques by the farming community. 

The striped catfish (P. hypophthalmus) is a migratory riverine species that undertakes long-distance migrations of more than several hundred kilometres between its upstream refuges and spawning habitats and its downstream feeding and nursery habitats (Van Zalinge et ai, 2002 Baran, 2006). The life-cycle of the striped catfish is intimately tied to the annual monsoon... 

The success of the artificial seed production is considered to be one of the key drivers for the explosive growth of the striped catfish in Vietnam (Phuong and Oanh, 2009). The production of hatchery-reared seed has increased rapidly during the past years larvae and fingerfing production increased 18-fold and 26-fold, respectively, between 2002 and 2011 (Fig. 16.3). The seed demand is mostly for fingerfing size for grow-out stocking. 

L3 Historical developments in striped catfish hatchery technology... 

Initially, the seed stock for striped catfish farming was wild-caught, primarily from Cambodian waters at the confluence of the Mekong, Bassac and Tonle Sap Rivers, the main nursery grounds of this species (Nguyen, 2009). However, the Cambodian authorities banned the capture of wild stocks in... 

Fig. 16.3 Growth of striped catfish larvae and fingerlings in Vietnam (compiled by...

Ngor, 1999 Nguyen, 2009 Phuong and Oanh, 2010) and this ban led to a hiatus in the expansion of striped catfish farming. However, it also led to a concerted effort to study and develop artificial propagation techniques. 

Striped catfish seed production induced breeding in hatcheries... 

Striped catfish seed production in Vietnam is structured within two main sectors-hatchery and nursery (Bui et aL, 2010) (Fig. 16.4). Hatcheries produce large numbers of larvae which are mostly sold to nursery farms (94%), while the nursery sector grows fry and fingerling for sale to the grow-out farms. 

Fig. 16.4 Structure of the hatchery and nursery sectors of the striped catfish seed production in the Mekong delta and the movement of stock between each sector...

Both manufactured pelleted feed and farm-made feed are used for striped catfish broodstock, singly or in combination, the latter being used more as a conditioning diet. The formulation of farm-made feed is relatively simple, often comprising a combination of locally available ingredients such as sun-dried trash fish (20%), fresh trash fish (40%), rice bran (30%) and vegetable (10 %) (Bui et al, 2010 Phuong, 2012). 

The striped catfish can reach full maturation in captive conditions and can be induced to spawn (CAB International, 2006). The fish spawns throughout the year, but the peak breeding period is in May-July (as in nature), which corresponds to the onset of the rainy season (Bui et, 2010). Good quality broodstock from potential broodstock ponds are normally selected, based almost entirely on farmer experience, and transferred to maturation ponds for induced spawning about two to three months prior to spawning. 

There are several hormones and stimulating agents used to induce the spawning in striped catfish, e.g. hCG (human chorionic gonadotropin), ovaprim and pituitary gland. However, hCG is most commonly used because of its proven high efficacy. hCG is injected in females at doses of 200-65(X) lU/kg at a time and may be injected up to four or five times before... 

Table 16.1 Hormone (hCG) dose rates and timing of hormone injection used to induced spawning in the striped catfish...

A dry fertilisation method is normally used for the striped catfish, when eggs and nfilt are mixed gently. Fertilisation solution (containing 3 g urea and 4 g salt in 1 L of water) is added to the mixture of eggs and milt to... 

Striped catfish seed production larval and fry nursing... 

Larvae of the striped catfish are cannibalistic, usually causing low survival rate during the first days of the nursing period. Low stocking density and creation of natural food in rearing water are very important to reduce this mortality. 

The larvae of the striped catfish have to be transferred to rearing tanks or ponds within 24 h after hatching and fed five food (Fig. 16.13). Good quality... 

Advances in aquaculture hatchery technology Table 16.2 Feeding table for the striped catfish larvae... 

Table 16.4 Factors affecting the yield, production costs and net income of nursery rearing of striped catfish...

The demand for striped catfish seeds will increase in the coming years to keep pace with the increase in nationally planned production. The induced spawning technique of the striped catfish is relatively well developed and... 

DE SILVA s s and phuong n t (2011) Striped catfish farming in the Mekong Delta, Vietnam A tumultuous path to a global success. Reviews in Aquaculture, 3,45-73. 

LEFEVRE s, HUONG D T T, WANG T, PHUONG N T and MARK B (2011) Hypoxia tolerance and partitioning of bimodal respiration in the striped catfish Pangasianodon hypophthalmus). Comparative Biochemistry and Physiology, Part A, 158, 207-214. 

NGUYEN T T T (2009) Patterns of use and exchange of genetic resources of the striped catfish Pangasianodon hypophthalmus (Sauvage 1878). Reviews in Aquaculture, 1,222-229. 

PHAN L T, BUI T M, NGUYEN T T T, GOOLEY G J, INGRAM B A, NGUYEN H V, NGUYEN P T and DE SILVA SENA s (2009) Current status of farming practices of striped catfish,... 

PHUONG N T (2012) On-farm feed management practices for striped catfish Pangasianodon hypophthalmus) in Mekong River Delta, Viet Nam, in Hasan M R and Shipton T (eds) On-farm feeding and feed management in aquaculture. Fisheries and Aquacultnre Technical Paper. Rome FAO (in press). 

PHUONG N T and oanh d t h (2010) Striped catfish Pangasianodon hypophthalmus) aqnaculture in Viet Nam An nnprecedented development within a decade, in De Silva S S and Davy F B (eds) Success Stories in Asian Aquaculture. Amsterdam Springer-IDRC-NACA, 133-150. 

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