Browsing by Author "JAWAHAR, P"
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ThesisItem Open Access BIOMASS AND SEASONAL VARIATION OF PLANKTON DIVERSITY IN SEAGRASS AND CORAL REEF ECOSYSTEMS OF MANDAPAM COAST IN GULF OF MANNAR(Fisheries College and Research Institute, Thoothukudi, Tamil Nadu Dr.J.Jayalalithaa Fisheries University, 2017) DEEPIKA, S; SRINIVASAN, A; PADMAVATHY, P; JAWAHAR, PThe present study was conducted to assess the plankton species diversity, biomass and its seasonal variations in the three coastal locations in the near shore waters of Mandapam viz. Chinnapalam (station 1 – coastal water with seagrass beds), Shingle Island (station 2 - coastal water with coral reefs) and Kundhukal (station 3 - coastal waters without seagrass and coral reefs as control station). Monthly sampling was carried out from September 2016 to May 2017 in all the three stations. The overall minimum and maximum values of surface water temperature, depth, pH, salinity, dissolved oxygen, nutrients (nitrite, nitrate, phosphate and silicate), ammonia, BOD, COD, gross primary productivity and chlorophyll-a in all the three stations were between 25 and 30⁰C, 0.5 and 1.15 m, 7.68 and 8.23, 31 and 36 ppt, 2.68 and 4.69 ml. l-1, (0.0186 and 0.6318 μg-at-NO2-N.l-1, 0.0005 and 0.049 μg-at-NO3-N.l-1, 0.1123 and 1.1621μg-at- PO4-P.l-1, 0.084 and 1.981μg-at- Si.l-1), 0.0012 and 0.168 μg-at-NH3-N.l-1, 0.22 and 3.12 ml.l-1, 0.32 and 3.84 mg.l-1, 0.0737 and 1.194 mgC.m-3h-1 and 0.01 to 2.11 mg.m-3 respectively. All the water quality parameters were found to be within the levels prescribed for coastal waters. During the study period, a total of 69 species of phytoplankton and 65 species of zooplankton were recorded. Of these 60, 46 and 62 species of phytoplankton and 59, 49 and 59 species of zooplankton were observed in the stations 1, 2 and 3 respectively. The minimum and maximum number of phytoplankton ranged from 11 to 30, 10 to 18 and 12 to 29 at stations 1, 2 and 3 respectively. The minimum and maximum number of zooplankton ranged from 18 to 40, 16 to 23 and 19 and 36 at stations 1, 2 and 3 respectively. In station 1, the density of phytoplankton and zooplankton ranged between 89 and 1123 cells.l-1 and 126900 and 667400 nos.m-3 respectively. The density of phytoplankton and zooplankton ranged between 61 and 122 cells.l-1 and 108100 and 512300 nos.m-3 respectively in station 2, whereas the station 3 had the range of density of phytoplankton and zooplankton between 70 and 1081 cells.l-1 and 89300 and 935300 nos.m-3 respectively. The eggs of Caranx sp. were observed during January 2017 and February 2017 at station 1 and the same was observed during November 2016, January 2017, and April 2017 at station 3. The eggs of clupeid group were also observed during January 2017 at station 3. Few species of fish larvae were observed during March 2017 at station 1 and during February 2017 and May 2017 at station 3. The species richness index varied from 2.15 to 5.38, 1.88 and 3.43, and 2.27 to 4.90 at stations 1, 2 and 3 for phytoplankton respectively. For zooplankton it varied from 3.33 to 7.13, 2.97 to 4.30 and 3.64 to 6.29 for stations 1, 2 and 3 respectively. The species diversity index for phytoplankton and zooplankton varied from 0.43 to 1.20 and 0.88 to 1.58, 0.89 to 1.25 and 0.96 to 1.32 and 0.89 to 1.26 and 1.16 to 1.51 for stations 1, 2 and 3 respectively. Phytoplankton density showed a significant (at 5% level) positive correlation with nitrate and salinity in stations 1 and 3 respectively. Zooplankton showed significant (at 1% level) positive correlation with salinity and net primary productivity in station 2. The study concluded that the seagrass ecosystem is more productive with high plankton biomass and diversity than the coral reef ecosystem.ThesisItem Open Access EFFECT OF HUMAN CHORIONIC GONADOTROPIN HORMONE ON GROWTH AND MATURATION OF ROSY BARB, BARBUS CONCHONIUS (HAMILTON-BUCHANAN)(Fisheries College and Research Institute, Thoothukudi, Tamil Nadu Dr.J.Jayalalithaa Fisheries University, 2017) Deepa Suman, J; RAJAGOPALSAMY, C.B.T; JAWAHAR, P; V, NThe Rosy barb, Barbus conchonius belonging to the family cyprinidae is an excellent community fish that has high domestic and export value in ornamental fish trade. The presence of Rosy barbs in the aquarium fascinates the spectator. Voluminous information is available regarding the use of Human chorionic gonadotropin in maturation, but only few works were carried out in ornamental fishes. The present investigation was designed to study the effect of human chorionic gonadotropin hormone on the growth, maturation and spawning of Rosy barb, Barbus conchonius (Hamilton – Buchanan). The HCG hormone (HuCoG 5000 IU) was incorporated into the pellet feed at 100 IU (T1), 300 IU (T2), 700 IU (T3) and 1000 IU (T4) concentrations. The experiment has been carried out for a period of 165 days. The influence of different HCG hormone concentrations on body weight, standard length and specific growth rate were tested and the statistical analysis showed the significant difference at P<0.01 level among the Treatments and Culture period. Mean length gain and per day mean length gain, mean weight gain and per day mean weight gain were found to be high in Treatment 2. The HCG hormone induced the maturation of Rosy barbs reared in the Treatments as in the following descending order i.e., T2, T3, T4, T1 and control experimental tanks. The maximum values of GSI was observed in Treatment 2 rosy barbs (16.36%) with the Control rosy barbs showing the lowest value (13.13%) in 165 days of culture period. The higher values of fecundity in Rosy barbs were recorded in Treatment 2 (910) with the lower values in Control (837). Age at first spawning was earlier (142 days) in Treatment 2 followed by Treatment 3 (157 days). The total number of eggs spawned was high in T2 Rosy barbs. High hatchability (95.71%) and high fertilization rate (95.88%) were recorded from Treatment 3 Rosy barbs. The embryonic and larval development of Rosy barb was studied for a period of 26 days till the larva reached to juvenile. The results of the present study infer that 300 IU HCG was the optimum dose to achieve maximum growth, early maturation, high fecundity in Rosy barb, Barbus conchonius.ThesisItem Open Access EVOLVING SERIAL COLLAPSIBLE FISH TRAP WITH UPGRADED MATERIALS AND FUNNEL DESIGNS(Fisheries College and Research Institute, Thoothukudi, Tamil Nadu Fisheries University, 2017) ARUN JENISH, D; NEETHISELVAN, N; SUNDARAMOORTHY, B; JAWAHAR, PA study on the comparative analysis of catch performance of two types of serial collapsible fish traps namely Type-1 traps and Type-2 traps was carried out. Funnels of four different shapes such as (i) Rectangular, (ii) Oval, (iii)Heart-in and (iv)Circular were fabricated with two different rear end opening perimeter of 560mm and 700mm so as to fit in Type-1 and Type-2 traps respectively. Two trap units were fabricated under each type of traps. Each trap unit consisted of six trap chambers so as to enable to fit four types of funnels each in triplicate. The main characteristic feature of the Type-1 traps was that it was made up of Galvanized steel tubes having 2.5 cm thickness. Further, the rear end funnel opening of Type-1 traps had smaller perimeter of 560 mm. Type-2 trap frames were fabricated with PVC rods of 2.5 cm thickness. Further, the rear end funnel opening of Type-2 traps had relatively a larger perimeter of 700 mm. The experimental fishing was carried out for six months from November 2016 to April Title :Evolving serial collapsible fish trap with upgraded materials and funnel designs Name : D.Arun jenish Degree : M.F.Sc. (Fisheries Engineering and Technology) Chairman : Dr.N.Neethiselvan Department :Department of Fishing Technology and Fisheries Engineering College :Fisheries College and Research Institute, Thoothukudi Year and University :2017, Tamil Nadu Fisheries University, Ngapattinam. 2017 at Mandapam fishing village of Ramanathapuram district of Tamil Nadu at the rate of 4 fishing trips per month. The traps were operated from a Vallam (a traditional craft of Thoothukudi origin) in fishing grounds three nautical mile off the coast of Mandapam (Lat: 090 14.141‟N; Long: 0790 09.433‟ E) keeping the total soaking duration of traps as 24 h. Significant difference could be observed with respect to catch rate of different species caught irrespective of the types of traps (P<0.01). The difference in shape of rear funnel opening was found to be responsible for the significant difference in the catch rate of the experimental traps(P<0.05). Significant difference could also be observed in the catch rates of both in Type-1 and Type-2 traps with respect to different months (P<0.01). The overall catch rate of Type-1 traps was about 2 times higher (13 Nos/ soaking day) than that of Type-2 trap (7 Nos/ soaking day). Epinephelus malabaricus was found to be the dominant species in Type-1 traps in terms of numbers; where as Acanthurus bleekeri was found to be the dominant species in Type-2 traps. Epinephelus malabaricus ranked first in terms of weight in both Type-1 and Type-2 traps. The traps fitted with the funnel having Oval shaped rear end opening performed better than traps fitted with other shapes of funnels both in Type-1 and Type-2 traps. Considering the Net returns, fitting all the 6 chambers of Type-2 traps with O1 funnel was found to be the best combination to get possible highest net return of Rs 55,011 for 25 fishing days using 30 Trap units per fishing trip.ThesisItem Open Access ROLE OF NEUROENDOCRINE MODULATORS ON GONADAL MATURATION IN RAINBOW SHARK, (Epalzeorhynchos frenatum)(Fisheries College and Research Institute, Thoothukudi, Tamil Nadu Dr.J.Jayalalithaa Fisheries University, 2015) ELAKKANAI, P; Francis, T; JAWAHAR, P; PADMAVATHY, PThe present investigation was undertaken to ascertain the effect of neuroendocrine modulators on gonadal maturation in Rainbow shark, Epalzeorhynchos frenatum. The gonadal maturation was observed using three different hormones viz., GnRH, hCG and synthetic Kisspeptin-10. The fishes were divided into four groups .First, second and third groups of fishes were injected intramuscularly with GnRH, hCG and synthetic Kisspeptin-10 respectively. The fourth group was maintained without any hormone injection as control. A duplicate set was also maintained simultaneously. Each hormone was injected at three different concentrations. Male and female fishes were stocked in separate tanks. Monthly sampling of gonads and blood samples were also collected from control and hormone (GnRH, hCG and synthetic Kisspeptin-10) injected fishes during the experimental period to assess the maturation using various reproductive parameters, such as Gonadosomatic index (GSI), fecundity and ova diameter. GSI values of synthetic Kisspeptin-10 injected fishes were higher than other two hormones and control fishes in most of the sampling period. The synthetic Kisspeptin-10 injected male and female fish attained highest GSI values (1.49 & 8.7) at the end of the experimental period. Maximum fecundity of 5040 eggs was observed at the end of the sampling period in the synthetic Kisspeptin-10 hormone treated fishes. The maximum ova diameter of 0.84 mm was observed from synthetic Kisspeptin-10 injected fishes, whereas in control fish it was 0.56 mm. Changes in the testosterone and estradiol-17 level was observed from the hormone injected fishes when compared to the control fish. Maximum testosterone and estradiol-17 level of 8.34 ng/ml and 439 pg/ml of blood was observed from synthetic Kisspeptin- 10 injected male and female fishes respectively. Histological changes in the ovary and testis of synthetic Kisspeptin-10 injected male and female fish showed the presence of advanced maturity stages of gonads during all sampling periods. Four types of growing oocytes namely perinucleolar, previtellogenic, vitellogenic and hydrated oocytes were observed in the ovary of E. frenatum. Similarly in testis, five types of spermatogenic cell types were identified namely spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids and spermatozoa. Induced breeding experiments were carried out with GnRH, hCG and synthetic Kisspeptin-10 at the rate of 0.5 mg/kg, 1500 IU/kg and 150 μg/kg respectively. Among the three treatments, fishes induced with 150 μg/kg body weight of synthetic Kisspeptin-10 performed better result than the other two groups of the hormone induced fishes.ThesisItem Open Access STOCK ASSESSMENT OF SELECTED SCIAENID SPECIES OF THOOTHUKUDI COAST(Fisheries College and Research Institute, Thoothukudi, Tamil Nadu Dr.J.Jayalalithaa Fisheries University, 2007) SANTHOSHKUMAR, S; Rajagopalsamy, C.B.T; JAWAHAR, P; AHILAN, BA detailed investigation was undertaken to study the stock assessment of selected sciaenid species of Thoothukudi coast. Specimens for the present investigation were collected six times in a month from the commercial trawl catches of Thoothukudi coast. The study was carried out for one year from July 2006 to June 2007. Availability of sciaenid species in trawl net catch along Thoothukudi coast was recorded. Occurrence and abundance of Nibea maculata and Otolithes ruber were recorded. Data on catch composition and CPUE of N. maculata and O. ruber from trawl nets were collected. Average monthly catch effort and CPUE of N. maculata and O. ruber were recorded. Length frequency distributions of these species were studied. Length-weight relationship, growth parameters, mortality parameters were estimated for N. maculata and O. ruber using FAO-ICLARM Stock Assessment Tools (FiSAT) software. Recruitment pulse of N. maculata and O. ruber were analysed with time series length frequency data. Total stock, annual stock, MSY and exploitation ratio of N. maculata and O. ruber were estimated and yield isopleth was plotted for both the species. Nibea maculata and O. ruber showed year round occurrence at Thoothukudi coast. The annual catch of N. maculata and O. ruber were 830.7877 tonnes and 93.7921 tonnes respectively. The major catch of N. maculata and O. ruber were recorded from June to August and June to July respectively. The catch per unit effort was found to be high in the month of June, July and August for N. maculata and June and July for O. ruber. The length-weight relationship of N. maculata showed isometric growth and the weight gain of O. ruber in relation to the total length was found to be lower in Thoothukudi coast. The estimated life span of N. maculata was 4.3 years and it was 11 years for O. ruber. Significant seasonal oscillation in growth was found in N. maculata and hence seasonalised von Bertalanffy’s growth equation was employed to fit the growth curve. There was no growth oscillation in O. ruber and hence generalised von Bertalanffy’s growth equation was employed to fit the growth curve. An inverse relationship was observed between growth co-efficient and asymptotic length for N. maculata and O. ruber. The ‘K’ value of N. maculata was high, inferring fast growth rate and it was low in O. ruber, inferring slow growth rate. The estimated total instantaneous mortality (Z) of N. maculata was 2.730 with low fishing mortality (1.0649) and which infers less exploitation in this species. The ‘Z’ value of O. ruber was found to be 2.450 with high fishing mortality (1.7373) and which infers slightly over exploitation in this species. Recruitment of N. maculata was recorded round the year with a peak in December and the same in O. ruber was also observed throughout the year with two peaks one during January and February and other in September. The Virtual Population Analysis revealed that fishing pressure was more in length group of 15 cm to 20 cm for N. maculata and 18.5 cm to 25.5 cm for O. ruber. Based on the relationship between exploitation ratio and yield per recruit of N. maculata, it could be inferred that this species is less exploited and the present level of effort should be increased by 27.82 % to achieve the optimal MSY level. In the case of O. ruber, present exploitation was more than the MSY level and the present effort could be reduced to 29.27 % to sustain the stock.