Browsing by Author "Duller, A. T."
Conference paperGF 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 CenterThe 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.
Survival of yolk-sac larvae of grouper (Epinephelus suillus) under simulated transport conditions. GF Quinitio, JD Toledo, AT Duller & DM Reyes Jr. - In P Lavens, P Sorgeloos, E Jaspers & F Ollevier (Eds.), Larvi '91. Short Communications and Abstracts of Contributions Presented at the International Symposium on Fish and Crustacean Larviculture, 27-30 August 1991, Gent, Belgium, 1991 - European Aquaculture Society. EAS Special Publication No. 15Transport of live fish is a routine activity in aquaculture. Various transport techniques have been reported by Berka. Transport of grouper eggs (Epinephelus suillus) between fisheries stations in Thailand is being conducted. However, no report has been made on transport of yolk-sac larvae of this fish. In the Philippines transport of eggs poses difficulties, particularly for hatcheries which are distant from the broodstock rearing site since spawning occurs between 1600 and 1800 h. Eggs can only be collected the following morning and hatching starts around 1200-1300 h (20 h after fertilization). Thus it seems advisable to transport yolk-sac larvae rather than eggs of grouper under such conditions. This study was conducted to determine the feasibility and optimum loading density of transporting grouper yolk-sac larvae for about 2 h.