Now showing items 1-5 of 5

    • Article

      Effect of varying dietary crude protein levels on spawning frequency and growth of Sarotherodon niloticus breeders 

      CB Santiago, MB Aldaba & MA Laron - Fisheries Research Journal of the Philippines, 1983 - Fisheries Research Society of the Philippines
      Four-month-old S. niloticus breeders were fed with dry pellets containing 20 to 50% crude protein in two separate experiments. Their frequency of spawning and their growth in length and weight were determined over a 16-week period for each experiment.

      Spawning frequency and total growth (body weight gain plus total weight of eggs collected) of females had a tendency to increase as the dietary crude protein level increased to 50%. However, there were no significant differences (P0.05) among mean spawning frequencies and mean numbers of eggs per spawning. Although better growth was obtained with higher dietary crude protein, there was no significant correlation between a brooder’s weight and the number of eggs spawned each time.

      There was an increase in mean weight gain of the males as the dietary crude protein increased up to 50%. Weight gains of fish fed with 50% crude protein were 48.7% and 73.8% greater in Experiment I and II, respectively, than those fed with 20% crude protein.
    • Article

      The effects of artificial diets on fry production and growth of Oreochromis niloticus breeders 

      CB Santiago, MB Aldaba, EF Abuan & MA Laron - Aquaculture, 1985 - Elsevier
      Tilapia breeders were fed with pelleted supplemental diets containing 20 or 40% crude protein at a daily feeding rate of 1% of fish biomass for 24 weeks in cages and tanks. Breeders were weighed and fry were collected at 3-week intervals. The 40% protein diet consistently gave the highest fry production and growth of breeders. The 20% protein diet gave variable results; fry production and growth were comparable to those of breeders fed with the 40% protein diet in some trials but significantly low in others. Breeders without supplemental feeding invariably had the least number of fry and the lowest body weights.
    • Article

      An evaluation of formulated diets for Nile tilapia fingerlings 

      CB Santiago, OS Reyes, MB Aldaba & MA Laron - Fisheries Research Journal of the Philippines, 1986 - Fisheries Research Society of the Philippines
      Nine practical diets were formulated and prepared as dry pellet crumbles. These were fed to two batches of Nile tilapia fingerlings (0.753g initial mean body weigt for trial I, and 0.961g for trial II) at 10% of fish biomass daily for eight weeks in glass aquaria or wooden tanks. Diets 1, 2, 3 and 4 contained 20% crude protein (CP), diets 5 and 6 had 25% CP and diets 7, 8 and 9 had 30% CP.

      Mean weight gains were significantly different (P<0.05) among treatments in trial I and in trial II. There were also significant differents in weight gains of tilapia fingerlings fed diets of the same protein level. Diets with higher protein content did not necessarily produce better growth. Irrespective of the protein level, diets containing 18% or more fish meal (diets 3, 6, 7 and 8) gave higher weight increases compared to those containing 0 and 5% fish meal (diets 1, 2, 4, 5 and 9). Diets with ipil-ipil leaf meal or copra meas as sole or major protein source gave the lowest growth response. Of the nine diets, diet 6 produced the highest weight gain followed closely by diets 7 and 3 in both trials. Diets 6, 7 and 3 contained fish meal, soybean meal, copra meal and rice bran, among others. Feed conversion values were also better for these diets.
    • Article

      Influence of feeding rate and diet form on growth and survival of Nile tilapia (Oreochromis niloticus) fry 

      CB Santiago, MB Aldaba & OS Reyes - Aquaculture, 1987 - Elsevier
      Young Nile tilapia (12 mg mean body weight and 11 mm total length) were stocked at a density of 5 fish/l in twelve 50-l aquaria filled with 30 l of tap water. They were fed pellet crumbles containing 35% crude protein at various daily feeding rates expressed as percentages of fish biomass. Mean increases in body weight after 5 weeks were 63, 198, 232 and 228 mg for the 15, 30, 45 and 60% feeding rates, respectively, when ambient temperature ranged from 19 to 21°C. Corresponding survival rates were 53, 85, 87 and 84%. Growth and survival rates were enhanced significantly (P < 0.01) at the 30, 45 and 60% feeding rates.

      Two feeding trials were conducted to compare the growth and survival of fry fed pellet crumbles and an unpelleted form of the same diet. Results showed that growth and feed conversion were similar for both forms of diet. However, the survival rate of fry fed pellet crumbles was significantly higher (P < 0.01) than the survival rate of fry fed the unpelleted diet. Prior pelleting of the formulated diet for the tilapia fry given at 30% to 45% of fish biomass daily ensured high survival, fast growth and efficient feed conversion.
    • Article

      Reproductive performance and growth of Nile tilapia (Oreochromis niloticus) broodstock fed diets containing Leucaena leucocephala leaf meal 

      CB Santiago, MB Aldaba, MA Laron & OS Reyes - Aquaculture, 1988 - Elsevier
      The effects of dietary leucaena leaf meal on reproductive performance and growth of Nile tilapia were determined. In the preliminary trial, sexually mature Nile tilapia were fed with a control diet or a test diet which had leucaena leaf meal as the only protein source for 24 weeks. Fish fed with the leucaena diet lost some weight and had significantly low (P<0.05) gonadosomatic index and fry production compared to those fed with the control diet. Subsequently, four isonitrogenous diets (20% crude protein) containing varying amounts of leucaena leaf meal (0, 20, 40 and 80%) were fed to Nile tilapia broodstock. Mean weight gain of the female fish decreased as the level of leucaena leaf meal in the diets increased. Females fed with the 80% leucaena diet invariably lost weight. Mean weight gain of males fed with the control diet and the 20 and 40% leucaena diets did not differ significantly (P>0.05). However, growth of males fed with the 80% leucaena diet was remarkably low. Fry production was highest for those fed with the control diet and the 20% leucaena diet. Fry production decreased slightly in fish fed with the 40% leucaena diet and was significantly low (P<0.05) for those fed with the 80% leucaena diet. The low fry production was preceded by a decrease in body weight of the female fish. However, the gonadosomatic indices of the females and the males were not markedly affected by the diets. On the basis of both fry production and growth, leucaena leaf meal should not exceed 40% of the diet of Nile tilapia broodstock.