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ThesisItem Open Access Commercial probiotics in tank reared nursery phase of freshwater prawn,Macrobrachium rosenbergii (De man, 1879)(Department of Aquaculture, College of Fisheries, Panangad, 2005) Beryl, E B; KAU; Mohanakumaran Nair, CThe efficacy of two commercial probiotics, Waves and Epicin on the growth and survival of M. rosenbergii PL and on the chemical and biological characteristics of water and soil were studied. The experimental set up consisted of fiberglass tanks of 70 l capacity with two treatments and a control, each with 5 replicates. Soil from a fishpond was filled to a height of 5 cm and water filled to a height of 25 cm. The post larvae were stocked @ 500 no/m2 and mild aeration provided. Commercial freshwater prawn feed starter 1 (Higashi) was given @ 100% of body weight. Analysis before the introduction of probiotics showed the presence of microorganisms such as E. coli, Salmonella, Hafnia alvei, Faecal Streptococci, Aeromonas caviae, A. sobria, A. hydrophila and Enterobacter aerogenus in the water and soil. Enterobacteria such as Enterobacter aerogenus, Hafnia alvei, Aeromonas sobria and A. hydrophila were present in the PL. The probiotics Waves and Epicin were added @ 0.5 ppm and 0.25 ppm respectively to the experimental tanks once in ten days and the microbiological observations and water quality parameters were studied once in 15 days. The introduction of the probiotics increased the growth and survival and reduced the F.C.R. of M. rosenbergii in nursery system. The species composition of the bacteria in the soil, water and body of the animal were not affected by treatment with probiotics, other than that the E. coli present originally and continued in the control was not detected in the tanks treated with probiotics. The T.P.C. was also less in the treatments compared to the control. Probiotics considerably reduced the level of NH3-N in culture tanks. Epicin was found to have reduced the NH3-N level effectively than the Waves.ThesisItem Open Access Cryopreservation of spermatozoa of critically endangered yellow catfish Horabagrus Nigricollaris (Pethiyagoda & Kottelat 1994)(Department of Aquaculture, College of Fisheries, Panangad, 2007) Rajani Vadthya; KAU; Dinesh, KIn order to develop gene banking techniques aimed at conserving the critically endangered black collared yellow catfish of the Western Ghats, Horabagrus nigricollaris and popularize this species in the aquaculture scenario a study on cryopreservation of spermatozoa was undertaken. Freshly collected milt was observed for its characteristics. Well water was used to activate the milt in various stages of the experiment. There was no significant difference in motility of spermatozoa or percentage hatching from fresh and milt cryopreserved using 10% dimethyl sulfoxide (DMSO). Screening of four extenders (A, B, C and D) containing NaCl, KCl, CaCl2, NaHCO3, KH2PO4, MgSO4.7H2O, Na2H PO4 and Glucose at various proportions clearly indicated that the extender composition had significant effect on the percentage of motility, fertilization and hatching. Selected milt samples were preserved under cryogenic condition and utilized for experimental spawn production. The quality of milt samples was analyzed for the spermatocrit value, sperm density, pH, motility score and time: values obtained ranged from 57.8 to 59.8%; 16.5 x 109 to 20.9 x 109 spermatozoa/ ml of milt; 7.2 to 7.4; 4+ to 5+ (i.e. 80-100%) and 30 to 70 seconds respectively. The most promising combination was extender - A with 10% DMSO as the cryoprotectant. The ratio of milt and diluent was 1:4. Samples were equilibrated at 0°C ± 4°C on ice and vapourised over liquid nitrogen fumes for 10 minutes and finally stored in liquid nitrogen for three months. Stored milt samples were thawed and utilized to fertilize the eggs. Quick thawing procedure (27°C ± 2°C for 7 seconds) was followed. A French straw containing 0.5ml milt was found to be sufficient to fertilize 200 eggs approximately. Average fertilization % obtained was 30.3 ± 2.8 for extender- A against 35.8± 0.4 for the control. Mean hatching % obtained was 35.0 ± 4.7 for extender - A and 41.6± 4.4 for the control. No significant difference in fertilization success was found between cryopreserved sperm and untreated sperm from the same milt samples. Viable hatchlings were produced from milt that had been cryopreserved for three months indicating the feasibility of establishing a cryopreservation protocol to bank the genes and popularize the aquaculture of this critically endangered species. With the rapid global expansion of aquaculture, there is a need for year-round availability of larvae that could, to some extent, be met through cryopreservation of gametes.ThesisItem Open Access Utilization of water spinach Ipomoea aquatica leaf meal as protein source in the feed of Macrobrachium rosenbergii post larvae(Department of Aquaculture, College of Fisheries, Panangad, 2007) Sijimol, A P; KAU; Thresiamma JamesThe present study aimed to find out the feasibility of using water spinach leaves as a low cost plant protein source and dietary evaluation of the formulated diet through growth trials employing post larvae of Macrobrachium rosenbergii, thus to determine the optimum level of substitution of spinach leaf meal. The experiment was done for a period of 60 days. A comparison has also been made between the diets having various levels of inclusion of water spinach leaf meal over the control diet without spinach leaf meal. Five isonitrogenous test diets T1 to T5 were prepared with 30% crude protein. The feed ingredients used were clam meat, Ipomoea aquatica leaf meal, wheat bran, ground nut oil cake, tapioca flour, vitamin mineral mixture and sunflower oil. The control diet T1 was prepared by using all ingredients mentioned above, without Ipomoea leaf meal. The test diets T2, T3, T4 and T5 were prepared by using all ingredients mentioned above and replacing clam meat with water spinach leaf meal at inclusion levels of 12 %, 24 % 36 % and 48 % respectively. Results showed better growth rates in prawn post larvae fed with diets (T2) containing 12% Ipomoea leaf meal. Among the test diets, T2 recorded highest growth rate (603.63 mg). Specific growth rate, food conversion ratio and protein efficiency ratio also showed better performance of prawn post larvae fed on test diet with 12% inclusion of spinach leaf meal. The highest SGR (3.67) and PER (2.99) were recorded in prawns fed on diet T2 and lowest SGR (2.68) and PER (1.48) were obtained with diet T5. The survival rate of post larval prawns were not found to be significantly influenced by the various test diets used and the survival ranged from 77.5% to 82.5%.ThesisItem Open Access Effect of eyestalk ablation on the rematuration of female macrobrachium rosenbergii (De Man) in captivity(Department of Aquaculture, College of Fisheries, Panangad, 2003) Vadher Kailashkumar Hirabhai; KAU; Aneykutty, JosephThe giant freshwater prawn, Macrobrachium rosenbergii is one of the commercially important spccces widely cultured throughout the tropics, subtropics and some parts of the temperate region. Non- availability of brood stock in sufficient numbers at appropriate time has been the greatest constraint for successful operations of prawn hatcheries. To avoid entire dependence on natural sources, development of brood stock of female prawns in captivity is essential. The objectives of the present study were to find out the role of eyestalk ablation on rematuration of spent female of M. rosenbergii in captive conditions and to study the histology of the ovary during rematuration of eyestalk ablated and unablated spent female of M. rosenbergii. In the rematuration experiment the effect of eyestalk ablation on moulting frequency, spawning frequency, larval hatch fecundity, incubation period, ovarian development and ovarian index of spent female of M. rosenbergii was evaluated for 60 days. The histology of ovary in M. rosenbergii during rematuration was also studied. The analysis of the result was done with student's t-test and paired t- test. A significant difference was observed in moulting frequency and spawning frequency of ablated and 'unablated spent female of M. rosenbergii. Larval hatch fecundity of ablated and unablated spent female of M. rosenbergii was not found to vary significantly. Significant difference was found in larval hatch fecundity after first time and second time hatching of both ablated and un ablated individuals. The incubation period was not found to vary significantly among ablated and unablated. However, slight reduction in incubation period was observed in ablated ones. Five histological stages of ovaries viz. previtellogenic stage, early vitellogenic, vitellogenic and late vitellogenic and matured oocytes were observed. In the histological sections of the ovaries, starting from spent ovary to the ripe ovary at weekly interval, similar type of oocyte development stages were observed in both ablated and unablated. IIowever, the size of largest oocyte in ablated was slightly higher than the size of oocyte in unablated at each week of development. It was observed in the present study that ovarian index of ablated spent female was higher than unablated at each week of development. The rematuration experiment has shown that eyestalk ablation significantly enhanced moulting frequency and spawning frequency but the effect was insignificant in terms of larval hatch fecundity and incubation period in spent female of M. rosenbergii. Insignificant increase in ovarian development and ovarian index were also observed in ablated spent female of M. rosenbergii.ThesisItem Open Access Biomodulation of non-specific immune response in the tiger shrimp Penaeus monodon fabricus with spirulina iccorporated diet(Department of Aquaculture, College of Fisheries, Panangad, 2002) Jadhav vishal Shripatrao; KAU; Devika, PillaiBlack tiger shrimp; Penaeus monodon is an important species cultured all over the world. However, disease outbreaks have caused senous economic losses in several countries. For successful farming of shrimps disease prevention is a prime necessity The present study was designed to assess the immunostimulating potential of Spirulina and to see its effect on growth as well as colour of P. monodon juveniles. In this study, juveniles of P. monodon were used for evaluating the effect of different levels of Spirulina on growth, food conversion ratio, food conversion efficiency, survival as well as prophylactic potency of Spirulina evaluated by proPhenoloxidase activity, antibacterial assay, haemagglutinin assay, phagocytosis and challenge study Effect of Spirulina on colour of shrimps was also studied. Five experimental diets designed as T I to T 5 were prepared by using clam meat, Spirulina, rice bran, cod liver oil and vitamin- mineral mix. The total protein content of all diets were kept near to 40% and Spirulina was incorporated at 0%, 10%, 20%, 30% and 40% in diets by replacing clam meat. Completely randomized design with five treatments each having four replications was used for analyzing the results. In each tank ten numbers of Penaeus monodon juveniles were kept. Feeding was done for a period of 35 days. The test animals fed with diet containing Spirulina up to 30% incorporation showed better growth, food conversion ratio and food conversion efficiency. But survival during experiment was not affected by the addition of Spirulina. Spirulina incorporated treatments showed higher phenoloxidase activity than control. Antibacterial activity was also observed in the treatments incorporated with Spirulina, while in control no antibacterial activity was observed. Result of agglutinin activity was not 99 clear as control also showed agglutination in undiluted haemolymph sample and partial agglutination in 1:2 dilution of haemolymph. Spirulina incorporated treatments showed agglutination up to 1:4 dilution of haemolymph. But in 1:4 dilution only partial agglutination was observed. Increased adherence of haemocyte to yeast cells was observed indicating higher phagocytic activity in the treatment incorporated with Spirulina, while adherence of haemocyte was rarely observed in control. On challenge with Vibrio parahaemolyticus, shrimps treated with Spirulina incorporated diet showed delayed mortality as compared to control. Spirulina treated shrimps showed darker colouration than control.ThesisItem Open Access Evaluation of spirulina fusiformis as a protein source in the diet of penaeus monodon fabricius(Department of Aquaculture, College of Fisheries,Panangad, 2008) Tank Ketan, Vallabhdas; KAU; Thresiamma, JamesThe blue green alga Spirulina fusiformis has been accepted as an ideal food organism since it has a high protein content of 60-65 %, besides being rich in vitamins, minerals, fatty acids (gamma-linolenic acid (GLA)) and antioxidant pigments such as carotenoids. The present study is aimed at finding out the feasibility of using Spirulina fusiformis as a protein source in the diet for black tiger shrimp Penaeus monodon (Fabricius). Six isonitrogenous test diets T1 to T6 were prepared with 40% crude protein. Clam meat was replaced with Spirulina at an inclusion level of 5%, 10%, 20%, 30% and 40%, and the substitution effect was compared with a control diet in which clam meat was the sole source of protein. The study was conducted for a period of 60 days employing Penaeus monodon postlarvae (0.04 g avg. weight) with six treatments and four replications. The postlarvae were stocked at the rate of 10 numbers per tank. On completion of the experiment the specific growth rate, food conversion ratio and protein efficiency ratio were superior in shrimp postlarvae fed with the test diet containing 20% Spirulina. The diet T4 (20% Spirulina) led to significantly higher growth response (p>0.05) than in other diets. Further increase in the Spirulina inclusion levels significantly decreased the growth and feeding performance. The highest SGR (6.82%) and PER (1.67) were recorded with diet T4 and lowest SGR (4.16%) and PER (0.62) were obtained with the dietT6. The percentage survival was significantly higher (97.5%) in T3 (10% Spirulina) and T4 (20% Spirulina). The best FCR was recorded for 20% Spirulina (1.49). The results suggest that Spirulina fusiformis cannot serve as the sole protein source in the diet of Penaeus monodon postlarvae but can be effectively used as a supplementary protein source.ThesisItem Open Access Utilisation of cocoa pod husk as a feed ingredient for Labeo rohita (Hamilton) fingerlings(College of Fisheries, Panangad, 2007) Navya, R; KAU; Shyama, SA 70 day study was undertaken to evaluate the use of cocoa-pod husk meal as a dietary ingredient for rohu, Labeo rohita (Hamilton) fingerlings. Six iso-nitrogenous diets (30% crude protein) were formulated. The five test diets had cocoa pod husk meal incorporated at 5, 10, 15, 20 and 25% inclusion levels. A fish meal-based diet devoid of cocoa pod husk meal served as the control. Feeding was done at 5% once daily. The test diets were acceptable to the fish and gave positive feed consumption and growth. Optimum performance in terms of weight gain was achieved by fish fed a diet with 20% inclusion level of cocoa pod husk meal. However, FCE, fish weight gain and SGR showed a decline in fish fed the test diet, particularly so in the 25% cocoa pod husk meal diet. The reduced fish growth was caused by the high fibre content of cocoa husk which resulted in low protein digestibilities during the study. No direct toxic effect of theobromine and other purine alkaloids in cocoa products were reflected in the study, cocoa pod husk can thus be safely recommended as a feed ingredient in supplementary diets for Labeo rohita, up to an inclusion level of 20%.ThesisItem Open Access Survey and disease surveillance of newly introduced L. Vannamei (Boone, 1931) in India(College of Fisheries, Panangad, 2011) Roshan Maria, Peter; KAU; Devika, PillaiP. monodon (tiger shrimp) was the most preferred cultured species in India, but repeated occurrence of diseases especially white spot disease (WSD) caused by white spot syndrome virus (WSSV) had a severe setback to the shrimp culture industry. This prompted the industry to actively promote the introduction of a non-native species, the Pacific white shrimp, Litopenaeus vannamei, as an alternative to P. monodon for commercial aquaculture operations in the country. The authority to issue licenses to take up L.vannamei culture was vested with the Coastal Aquaculture Authority (CAA), who issued licenses for 1,208 aqua farmers in 2009. Availability of SPF stock, ability to grow well even at high stocking densities, reduced days of culture (DOC), lesser protein requirement (28-35%) and demand in the international market attracted aquafarmers to switch to culture of L.vannamei. A survey carried out in the Nellore district of Andhra Pradesh to understand the level of acceptance and the nature of culture practice among the farms culturing L.vannamei revealed that only 33% of the farms surveyed had obtained permission from the CAA, 41% followed biosecurity measures and merely 10% had the facility for Effluent Treatment System. 53% practised chlorination and de-chlorination of water during water exchange and only 38% farms maintained trained personnel. It was observed during the survey that only 84% procured tested SPF seed from certified hatcheries. While 90-92% of yhe farms depended on pelleted feed, only 80-85% of the farms surveyed carried out regular monitoring every 1-2 weeks. Disease surveillance in the farms surveyed did not detect the presence of any of the major shrimp viruses (WSSV, IHHNV, MBV, HPV and TSV) in the 60 samples screened using molecular methods. However, Vibrio sp. was detected in samples exhibiting obvious signs of bacterial disease. High stocking densities without adequate number of aerators can be stressful to the shrimps and might be the reason for bacterial infection. Economic analysis indicates that L.vannamei culture is more profitable than P.monodon culture.ThesisItem Open Access Comparative evaluation of different feed ingradients for stinging catfish heteropneustes fossilis(Bloch)(College of Fisheries, Panangad, 2010) Kumar, Katya; KAU; Mohanakumaran, NairStinging catfish Heteropneustes fossilis (Bloch) is commercially and nutritionally important in India, fetching high price locally and enjoying good potential for aquaculture. One of the major limiting factors restricting the expansion of H. fossilis culture is the high cost of trash fish used as feed for its grow out. Trash fish supply is irregular and unreliable and not always recommended in fish culture. In the present study an attempt was made to evaluate different feed combination as replacement diet for trash fish in the growout of H. fossilis using three sources of protein. Three isonitrogenous diets containing 40% of protein viz. fish meal (FM), clam meat (CM) and soymeal (SM) as protein sources were tested, with five replications for each treatment, and fed to the fingerlings of H. fossilis of initial size.(11.22 ± 1.27g and 12.24 ± 0.40 cm), collected from the wild and acclimated for two weeks in freshwater and stocked in 380L capacity cement cisterns at a density of 10 numbers per tank, provided with soil substratum. Tapioca flour and vitamin mixture were added at the rate of 10% and 1% respectively in all the feeds, while rice bran constituted 36%, 18.6% and 23.3% in FM, CM and SM feeds respectively. The test feeds were fed to the fingerlings at the rate of 5% of body weight, twice daily for duration of 42 days. At the end of the trial, final length and weight measurement of each juvenile in treatments were made, and the data statistically analyzed, using One-Way ANOVA. Multiple comparisons of mean values were carried out using Tukey’s HSD test, and the means were compared using two sample Student’s t-test. Water quality parameters in the experimental tanks were monitored weekly. All the treatments recorded cent percent survival, and there was no significant difference in length gain among the three feeds. Although the highest weight gain was obtained from the FM (8.56 ± 2.40g), followed by SM (6.09 ±1.40g) and CM (5.68 ± 0.72g) respectively, statistical analysis revealed that there was no significant difference between FM and SM treatments, indicating that soymeal is equally good as fish meal. However the lowest food conversion ratio (FCR) of (2.74) for FM, followed by CM (4.07), and SM (4.53), which suggest that fish meal is the best source of protein in the feed for the culture of H. fossilis, but soymeal could also be used to replace fish meal, upon further refinement of growth trials. Highest ammonia was recorded in FM tanks, followed by CM and SM, which indicate that water quality needs to be closely maintained, when sources of animal protein are used in the feed of H. fossilis. Additional research is recommended, supplementing the deficient amino acid lysine in soymeal, which might perhaps improve the weight gain and FCR of H. fossilis fingerlings.