Showing items related by title, author, creator and subject.

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  Conference paper

  Status of the Mekong giant catfish, Pangasianodon gigas Chevey, 1930 stock enhancement program in Thailand 

  N Sukumasavin - In JH Primavera, ET Quinitio & MR Eguia (Eds.), Proceedings of the Regional Technical Consultation on Stock Enhancement for Threatened Species of International Concern, Iloilo City, Philippines, 13-15 July 2005, 2006 - Aquaculture Department, Southeast Asian Fisheries Development Center

  The Mekong giant catfish (Pangasianodon gigas Chevey, 1930) is one of the largest freshwater fish in the world, measuring up to 3 m in length and weighing in excess of 300 kg. It is endemic to the Mekong River Basin area. It is found in Tonle Sap Lake, Tonle Sap River, and the Mekong River. It is not known to occur in the upper 2,000 km of the Mekong River. The current extent of occurrence is estimated at around 4,150 km. Historical reports indicate that the species was abundant in the early 1900s with 40-50 fish caught yearly in Nong Khai Province, north-east Thailand. However, since that time the number of fish caught has declined. This paper discusses several important information about Mekong Giant Catfish, such as rarity and size, natural food, natural spawning season and spawning grounds, and age and size at first maturity. Moreover, the breeding program and the stock enhancement activities of the Thai Department of Fisheries were also presented in the paper.
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  Conference paper

  LHRHa and pimozide-induced breeding in the catfish, Clarias macrocephalus (Gunther) 

  JD Tan-Fermin, RSJ Gapasin, AM Tan, MA Garcia & AC Emata - In CL Marte, GF Quinitio & AC Emata (Eds.), Proceedings of the Seminar-Workshop on Breeding and Seed Production of Cultured Finfishes in the Philippines, Tigbauan, Iloilo, Philippines, 4-5 May 1993, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center

  Clarias macrocephalus is endemic yet dwindling freshwater foodfish in the Philippines. Induced breeding protocol was developed by monitoring the size and maturation of eggs at 0-48 h after a simultaneous injection of luteinizing hormone-releasing hormone analogue (LHRHa; 0.0005 - 0.10 µg/g BW) and pimozide (PIM; 1 µg/g BW). Based on its similar osmotic pressure with catfish plasma, eggs were fixed in 1% phosphate-buffered formalin. Mean egg diameter of fish that were induced to mature increased during ovulation. Oocyte maturation, indicated by oocytes with germinal vesicle breakdown (GVBD), was observed at least 12 h post-injection in fish given 0.01 - 0.10 µg LHRHa + 1 µg PIM/g BW, followed by ovulation 4 h thereafter. Results showed that a simultaneous injection of C. macrocephalus with 0.05 µg LHRHa + 1 µg PIM/g BW at 1800-1900 h followed by stripping at 16-20 h post-injection resulted in high ovulation, fertilization and hatching rates.
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  Conference paper

  Weaning of the Asian catfish, Clarias macrocephalus Gunther, larvae to formulated dry diet 

  AC Fermin & MEC Bolivar - 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center

  Two feeding trials lasting 10 days each were conducted to determine the weaning time in the Asian catfish, Clarias macrocephalus, larvae to dry diet feeding. Three-day-old catfish larvae were fed newly-hatched Artemia nauplii for 2,4, and 6 days after which ad libitum feeding with a commercial feed (trial 1) or a formulated diet (trial 2) was started. Fish fed exclusively dry diet (0-day Artemia feeding) or those fed only Artemia for 10 days served as the controls. In trial 1, fish fed Artemia at different durations had significantly higher growth and survival than those reared exclusively on dry diet. In trial 2, percent survival was not significantly different among fish with or without Artemia pre-feeding. However, fish had significantly higher final body weight and SGR when reared initially on Artemia prior to dry diet than those fed exclusively dry diet. Based on the results, catfish larvae can be successfully weaned to dry diet after feeding Artemia for a maximum period of four days (ave. BW=12.25 mg).