Now showing items 1-6 of 6

    • Conference paper

      The commercial production of green grouper fingerlings, Epinephelus suillus, from wild caught fry - an industry experience 

      JV Juario, JR Silapan & LL Silapan Jr. - 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
      Wild-caught fry of the green groupers, Epinephelus malabaricus and E. suillus ranging in standard lengths (SL) from 1.5 to 3.0 cm were bought from different fry dealers all over the Philippines. These were reared from 1.0 to 2.5 months in 10 to 40 m3 (small) concrete tanks, in 240 m3 (large) concrete nursery tanks with sandy bottom, in 10 m3 hapa nets installed either in large nursery concrete tanks with sandy bottom or in 0.8 to 1.0 ha earthen ponds. The initial stocking density was 33-150/m3. When the fingerlings reached 5 to 7 cm SL, these were harvested and stocked in cages. The wild fry were fed adult brine shrimps for the first few days and later, trash fish. Rearing water in small concrete tanks was changed daily while that in large nursery tanks and hapas was changed only when dissolved oxygen level was about 4 ppt or lower. Survival rates ranged from 3% to 64%. Although survival rates varied, rearing grouper fry in hapa nets installed in earthen ponds were found to be the most suitable for the commercial production of grouper fingerlings to a size suitable for stocking in cages. The large variation in survival rates is attributed mainly to the quality of wild fry bought from different fry dealers all over the country and the occurrence of diseases during the culture period. The problems encountered in the commercial production of fingerlings are discussed.
    • Conference paper

      Effects of different fat sources on the egg quality of grouper, Epinephelus suillus 

      GF Quinitio, RM Coloso, A Duller & D Reyes - 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
      The effect of different fat sources on the egg quality of grouper, Epinephelus suillus eggs was evaluated. Fish in three tanks, each containing 3 females and 1 male, were fed various types of feeds namely: trash fish (control), trash fish + cod liver oil (treatment 1) and trash fish + SELCO, a lipid emulsion containing high levels of highly unsaturated fatty acid (HUFA) (treatment 2).

      Approximately 77.9 million eggs spawned from January to October 1992 by the control group, 40.0 million by fish in treatment 1, and 36.4 million by the treatment 2 group. Egg production (0.45 million eggs/kg BW) among the control group was significantly higher than treatment 2. Egg production of treatment 1 (0.06-0.36 million eggs/kg BW) was not significantly different (P<0.01) from the control group nor treatment 2 (0.02-0.30 million eggs/kg BW). Fertilization and hatching rates showed significant differences among the three groups with control > treatment 1 > treatment 2. There were no differences detected in the egg and oil globule diameters among the treatments. Crude protein and lipid levels of floating (good) and sinking (bad) eggs collected in February to March 1992, and August to September 1992 were similar in all treatments. Unfed larvae from treatment 1 survived until the fifth day after hatching while those in the control and treatment 2 groups lasted only until the third day. These results suggest that supplementation of cod liver oil and SELCO in the trash fish diet of E. suillus broodstock does not influence egg production, fertilization and hatching rates, and egg quality.
    • Conference paper

      Induced spawning of the mangrove red snapper, Lutjanus argentimaculatus 

      AC Emata, B Eullaran & M de los Santos - 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
      Wild-caught mangrove red snapper, Lutjanus argentimaculatus, reared for a year in 4.0 m diameter by 1.5 m deep circular concrete tank spontaneously matured and were used for induced spawning trials. On 19 August 1992, a sexually mature female (4.6 kg BW) and male (3.2 kg BW) fish were given a single intramuscular injection of 1500 IU human chorionic gonadotropin (hCG)/kg BW. Spawning occurred 27 h after injection with total egg collection of 1.3 M. Hatching occurred 16 h after spawning at 28 °C and 32 ppt. On 18 March 1993, the same male and female together with a newly-caught spermiating male (6.3 kg BW) were injected intramuscularly with 100 µg luteinizing hormone-releasing hormone analogue (LHRHa)/kg BW. Spawning occurred 44 hours after injection with the total egg collection of 0.7 M. Hatching occurred 16 hours after spawning at the same temperature and salinity as the first trial. The successful spawning trials encourage further research to determine the effective minimum dose of hCG and LHRHa.
    • Conference paper

      Larviculture of milkfish (Chanos chanos) in outdoor tanks 

      MN Duray - 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
      In the past, larviculture of milkfish depended entirely on the use of rotifers and brine shrimp nauplii and rearing trials were done under roofed facilities. Since the dietary value of live food varies according to culture and feeding conditions, rotifers were enriched with SELCO, a lipid emulsion containing high levels of highly unsaturated fatty acids (HUFA) prior to feeding the larvae. Alternatively, a microbound larval feed (Nosan R-1) was given as a supplement to rotifers during the first two weeks of culture. Larval growth was enhanced and survival was significantly improved when rotifers were enriched or supplemented with these diets. All rearing trials were conducted in 5-10 tons concrete circular/rectangular outdoor tanks.

      Verification runs on the use of HUFA-enriched rotifers to milkfish larvae were tried in two nearby private hatcheries. Results from mis collaborative work are presented.
    • Conference paper

      A review of grouper (Epinephelus suillus) fry production research in Malaysia 

      HM Ali - 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
      Research on grouper (Epinephelus suillus) fry production in captivity has been carried out in Malaysia since 1986 at Tanjung Demong Marine Finfish Production and Research Centre (TDMFPRC) but the breakthrough was only achieved four years later in 1990. Eggs were obtained through natural and induced spawning in tanks. Natural spawning of grouper in captivity seldom occurred and was unpredictable. However induced spawnings were successfully carried out by injecting human chorionic gonadotropin (hCG) intramuscularly at a dose of 500-1000 IU/kg fish.

      The results from several trials on larval rearing conducted since 1989 until recently showed that larvae obtained from natural spawnings survived longer with some reaching the juvenile stage. The highest recorded survival rate of 43 days posthatch (32.5 mm total length) was 12.1% at 28-32 °C water temperature. On the other hand, 100% mortality usually occurred in larvae obtained from induced spawning 7 days after hatching.

      The major constraints of grouper fry production in Malaysia are lack of male spawners, inconsistent and unpredictable natural spawning, small quantity of eggs released every spawning day, poor fertilization and hatching rate, weak hatchlings, and high mortality rate at the early stages of larval development. The latter is probably due mainly to problems on initial feeding.
    • Conference paper

      Tilapia breeding and seed production for brackishwater culture in the Philippines 

      RD Guerrero III, LA Guerrero & RG Cornejo - 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
      Tilapias are important foodfishes in the Philippines second only to milkfish. While farming of tilapias in freshwater ponds and cages is already established, there is a need for wider application of the available technologies for brackishwater culture. This paper presents the tilapia species used for brackishwater farming and the commercial methods applied for their hatchery/nursery rearing.