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Subject: Aquaculture × End date: 1994 × Start date: 1994 × Type: Thesis × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Conditions for oxygen-packed transportation of penaeus indicus seed
    (Department of Aquaculture, College of Fisheries, Panangad, 1994) Geetha Rani Mani, V; KAU; Jayasree Vadhyar, K
    The effect of four levels of packing density, (200PL/1, 300PL/1, 400PL/1 and 500PL/1), three levels of salinity (20ppt, 25ppt and 30ppt) and two levels of temperature (30_+ 1°C and 23 + 2°C) on the oxygen consumption rate of Penaeus indicus post-larvae (PL20) was investigated in a closed type respirometer. The dissolved oxygen in the test chamber decreased with the oxygen consumption of the animals. Oxygen consumption was found to vary with ambient oxygen levels at the different packing densities. Among the three salinities, and two temperatures, the lowest rate of oxygen consumption was recorded at 25ppt and 23 +_ 2°C. The effect of these factors on the duration and survival of transportation of the shrimp seed in specially designed hard plastic containers fitted with facilities for oxygen packing under uniform pressure (0.2 Kg/cm2) showed that oxygen packing in hypothermal conditions could help in increasing duration and survival. Salinity of 20-25ppt was found to give longer duration of survival. With increase in packing density, there was considerable reduction in the duration and survival of transportation of the seed. Cannibalism was observed as the major cause of mortality and it could be reduced by lowering of temperature. 200PL/1 could be transported with 100% survival within 6.5-8.5h at ambient temperature of 30+- 1°C under the afore-mentioned type of oxygen-packing. By lowering the temperature to 23 +-_ 2°C it was possible to safely transport with 100% survival the same numbers for more than 20h. Corresponding duration at 500PL/1 with 100% survival was 1-1.5h at ambient temperature and 4-5h at lowered temperature. To reduce cannibalism at ambient temperatures, hollow plastic translucent habitat material was incorporated into the oxygen-packed jars. This experiment was conducted at 25ppt salinity at different packing densities of 200PL/1, 300PL/1, 400PL/1 and 500PL/1. Relatively longer duration and higher survival was observed only at higher packing densities of 400PL/1 and 500PL/1 with the introduction of the habitat material. Water quality parameters in the experimental jars were analysed initially and finally at 70% survival rate. The reduction in dissolved oxygen levels in the oxygen-packed jars was well above the lethal limits even at the highest packing density of 500PL/1 at 70% survival. The decrease in dissolved oxygen levels and increase in ammonia-N and free carbon dioxide, differed with the duration of packing, temperature and packing density.
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    ThesisItemOpen Access
    Effects of various growth promoters in the diets of macrobrachium rosenbergii post larvae
    (Department of Aquaculture, College of Fisheries, Panangad, 1994) Boby Ignatius; KAU; Susheela Jose
    The present study was conducted to evaluate the efficiency of various growth promoters on the growth of Macrobrachium rosenbergii post larvae. The various growth promoters tried were antibiotic oxytetracycline, thyroid hormone thyroxine and the enzyme papain. Each growth promoter was incorporated in a casein based purified diet having a protein content of 36%.In the second experiment, the optimum level of growth promoter which showed the best performance in the first experiment was determined. The growth increment of prawns fed on casein based purified diets incorporated with antibiotic oxytetracyc1ine designated as diet T1 was 43.66mg, it was 35.064 mg for diet T2 - containing thyroid, and 32.172 mg for diet T3- containing papain. The growth increment for the control diet was seen to be 26.72 mg. Specific growth rate of the prawns from different treatments ranged from 1.73 to 2.52; with control diet showing the lowest and T1 the highest. Incorporation of the growth promoters in the feed has markedly reduced the food conversion ratio of the animals. Lowest FCR was obtained for the post larvae fed with oxytetracycline, while the highest was for the control, the range being 2.94 to 4.36. The protein efficiency ratio was highest being 0.9770 for the feeds containing oxytetracycline. The PER values for the control diet T0, diet T2 with thyroid, diet T3 with papain were found to be 0.6566, 0.8541 and 0.7576 respectively. Productive protein values were 8.995 for control diet, 13.4763 for diet with oxytetracycline, 11.7710 for diet with thyroid hormone and 10.4266 for diet with papain enzyme. The average survival rate during the experiment was 69.5%. The animals fed on antibiotic incorporated feed gave maximum survival of 72%, while the lowest rate of 66% was observed for thyroxine incorporated feed (T2). Analysis of the data on the various growth parameters in the experiment reveals that the antibiotic oxytetracycline gives better growth amongst the different growth promoters used. In the experiment II, four different levels of oxytetracycline were tested to find out the optimum level. The result of the study showed that, 10 mg/lOOg of feed is the optimum level of oxytetracycline which give maximum growth in Macrobrachium rosenbergii post larvae as indicated by overall growth , specific growth rate, food conversion ratio and protein efficiency ratio.
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    ThesisItemOpen Access
    Culture of spirulina fusiformis and its evalution as a proein source in the diet of entroplus suratensis
    (Department of Aquaculture, College of Fisheries, Panangad, 1994) Manju, K G; KAU; Thressiamma, James
    In the present investigation, suitability of Spirulina fusiformis as a dietary protein sources in E.suratensis was evaluated.The study was carried out on two aspects; (i) culture of the alga and (2) biological evaluation when incorporated in the diets. Among the different culture media tested for the culture of spirulina, Zarrouk medium was found to be the best followed by CFTRI medium. The rural waste medium and improved CFTRI medium also supported good growth, though at significantly lower level when compared to zarrouk medium and CFRI medium. In mass culture experiments, it was found that algal growth in rural waste medium was significantly higher than that in sewage medium. Biological evaluation was done by incorporating spirulina as the sole source of protein in diets fed to E.suratensis fingerlings. The diets were formulated at different levels of protein (20-50 %0. Best values of SGR, FCR, Apparent protein digestibility, PER and PPV were recorded at 35% protein. When compared with a fish meal based control diet, significantly lower PER and PPV values and higher FCR values were obtained with the spirulina diets, though significant difference was not observed in the survival rate. The effect of substitution of fish meal protein with that of algal protein was studied by gradually replacing the former by the latter in practical diets for E.Suratensis fingerlings. The results showed that replacement of fish meal protein upto 50% with spirulina protein in the diet of E.suratensis did not affect the growth performance and food utilization . Thus spirulina fusiformis seems to be a useful partial protein source in the diet of E.suratensis and its inclusion in the diet can replace 50% of the fishmeal protein which is of much economic importance as far as aquaculture industry is concerned.