Now showing items 1-3 of 3

    • Article

      The effect of lipid-enriched broodstock diets on spawning and on egg and larval quality of hatchery-bred rabbitfish (Siganus guttatus) 

      M Duray, H Kohno & F Pascual - The Philippine Scientist, 1994 - San Carlos Publications, University of San Carlos
      Three isocaloric and isonitrogenous diets formulated to contain 12 (diet A), 15 (B) and 18% (C) lipids were tested on hatchery-bred rabbitfish Siganus guttatus broodstock to determine their effect on spawning and quality of the eggs and larvae. The results show that fish on diet C has higher fecundity than those on diets B and A. Also, fish on diet C yielded eggs of better quality than either fish on diets B or A. This was indicated by spawns resulting in higher percentage of normal hatchlings, larger newly-hatched larvae and higher survival rates until the 14th day of rearing. Dietary lipid levels, however, have no remarkable effects on fertilization, yolk and oil globule volumes, hatching rate nor larval size at harvest.
    • Article

      Preliminary biological evaluation of some formulated feeds for P. monodon 

      F Pascual & L Bandonil - SEAFDEC Aquaculture Department Quarterly Research Report, 1977 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Rice bran is widely used by fish farmers as supplementary feed while soybean cake is used both as feed and as fertilizer in fishponds. Both fish meal and shrimp head have been found acceptable as feed ingredients. However, not much is known of the acceptability and efficiency of a mixture of these ingredients as feed for Penaeus monodon larvae. Ninety 127-day old P. monodon were measured for length and weight and were randomly divided into nine aquaria each containing 20 liters of water. These were fed lampirong for two months previous to the study. There were three replications for each treatment. Length, weight, and survival rates were used to compare the efficiency of the diets. Weighed amounts of pellets equivalent to 100% of the body weight were fed during the first three days and reduced to 50% thereafter. A stopwatch was used to determine the length of time that elapsed before the shrimps would approach the pellet. Ten shrimps approximately 4 months in age were placed in 10 liters of water in a 25-liter aquarium. Two grams of each pellet type were placed simultaneously on opposite sides of the aquarium. The time that elapsed from the moment the pellets sunk to the bottom up to the time that any one shrimp approached the pellets was recorded. The group fed the imported pellets gained the most. Those fed FP-2s-77 elongated faster than those fed FP-1s-77. Survival rate of those fed FP-2s-77 was 37% while those fed imported pellets was 73%. Both 1s and 2s pellets disintegrated in water easily but the imported pellets were stable even after six hours in water. The attractability test for the pellets showed that the prawns were more readily attracted to the pellets 1s and 2s than to the imported pellets.
    • Conference paper

      The use of substitute feeds in larval rearing of Penaeus monodon 

      E Quinitio, D de la Pena & F Pascual - In GL Rogers, R Day & A Lim (Eds.), Proceedings of the First International Conference on Warm Water Aquaculture-Crustacea, held on the Brigham Young University Hawaii Campus, February 9-11, 1983, 1983 - Brigham Young University Hawaii Campus
      Penaeus monodon larvae were stocked in 20-l conical plexiglass tanks in a water bath. Larvae were reared from protozoea to mysis I using feeds in combination with Tetraselmis sp. and Tetraselmis sp. alone. The feeds used were hard cooked ckicken egg yolk, beaten whole egg cooked in boiling water, cooked brown mussel, trash fish and soybean cake.Feeds were homogenized and pass through a 40 µm sieve prior to feeding. Three experimental runs were carried out.

      Survival of the fed with various feeds had no significant differences at the mysis stage. However, faster groowth rate was significantly obtained in the larvae fed with hard cooked chicken egg yolk.