Browsing by Author "Nirooparaj, B."
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Item Applicability of Brown Seaweed Species (Sargassum crassifolium) for Treating Lobster Farm Wastewater(Uva Wellassa University of Sri Lanka, 2021) Pirashanthy, K.; Rajapaksha, R.M.G.N.; Bambaranda, B.V.A.S.M.; Nirooparaj, B.; Chirapart, A.Wastewater generation in aquaculture farms, including all lobster culture practices is a serious issue in the industry. The present study was carried out at lobster farm located at Northern Province in Sri Lanka. Approximately 756,000 L of wastewater is generated on this farm annually and discharges wastewater without proper treatment to the natural environment. The wastewater discharged from lobster farm consists of organic and inorganic chemical components that can be caused potential environmental problems. Present study focused to investigate applicability of Brown seaweed Sargassum crassifolium biomass to efficient removal of nutrients (nitrogen and phosphorous) from the lobster farm wastewater. The Sargassum crassifolium is an abundant species in Northern Province, Sri Lanka. Seaweed biomass optimization was performed using three different seaweed biomasses, viz 20 g, 30 g and 40 g and 20 g (1 g L-1) identified as the efficient seaweed biomass. Wastewater initial physicochemical parameters pH (7.9 ± 0.02), Temperature (29 ± 0.04 ⁰ C), Salinity (36 ± 0.03 ppt), Dissolved Oxygen (3.58 ± 0.02 mg L-1), Biological Oxygen Demand (115 ± 0.05 mg L-1), Ammonia (1.37 ± 0.01mg L-1), Nitrite (0.143 ± 0.00 mgL-1), Nitrate (0.243 ± 0.01 mg L-1) and Phosphate (4.760 ± 0.02 mg L-1) were analyzed using the standard methods. Then wastewaters were collected from the farm and transferred to six glass tanks of 50 L capacity each. The seaweed was used at 1 g L-1 density in each tank except in the control tank. Complete randomized design was used to the experiment. Three replicates were used. Ammonia, Nitrite, Nitrate and Phosphate were analyzed once in three days from beginning to the end of the treatment period (28 days) to investigate the initial wastewater qualities and quality changes after Phycoremidiation. After phycoremidiation physiochemical parameters pH (7.4 ± 0.06), Temperature (29 ± 0.03 ⁰ C), Salinity (36 ± 0.05 ppt), Dissolved Oxygen (5.74 ± 0.04 mg L- 1), Biological Oxygen Demand (95 ± 0.03 mg L-1) were analyzed in wastewater. Sargassum crassifolium removed 1.19 ± 0.34 mg L-1 of Ammonia, 0.12 ± 0.03 mg L-1 of Nitrite, 0.14 ± 0.04 mg L-1 of Nitrate and 2.40 ± 0.72 mg L-1 of Phosphate. Nutrient removal amounts were significantly differed (P<0.05) between control and treatment tank. The weight gains Sargassum crassifolium during the study period was of 8.7 g thus, the seaweed has been utilized the nutrients present in the discharged waste waters. The results of the study concluded that the nitrogen and phosphorus in the lobster farm waste waters, can be effectively removed through Sargassum crassifolium. Keywords: Lobster, Sargassum crassifolium, Seaweed, PhycoremidiationItem Growth Performance of Holothuria scabra (Sand Fish) with Different Stocking Density in Open Sea Pen Culture in Jaffna, Sri Lanka(Uva Wellassa University of Sri Lanka, 2019-02) Mahishalini, V.; Athula, J.M.; Nirooparaj, B.Sea cucumber, Holothuria scabra is over exploited species in worldwide due to the high fishing intensity from the wild stocks. Sea cucumber pen culture practices are being expanded in Northern Province of Sri Lanka and presently operated more than 57 pen culture farms in the region. This research is intended to investigate the growth performance of H. scabra pen culture with different stocking densities to find out the most appropriate stocking density to introduce the farmers. This research was carried out in coast of Mankumpan village in Jaffna district, Sri Lanka. Early matured H. Scabra with average weight 49.78 g and average length 11.28 cm were collected from the Sea cucumber farmers. Four pens were constructed by using 5 mm mesh size high density polyethylene nets and wooden planks. The size of each pen was 25 m2. Early matured H. scabra was reared with stocking densities of 1, 2, 3 and 4 individual m2. Thirty percentage sample size was randomly collected in each pens to measure the growth parameter. Average length, weight and water quality parameters were measured twice a month and finally, survival rate was calculated. After 60 days of the culture period average specific growth rates were calculated twice a month and it shows 2.53 + 0.56 gday-1, 1.98 + 0.20 gday-1, 1.95 + 0.21 gday-1 and 1.08 + 0.27 gday-1 for pen 1, pen 2, pen 3 and pen 4 respectively. Data was analyzed using Minitab17 version by one-way ANOVA test. Average survival rates for pen 1 and pen 2 were recorded as 100% and for pen 3 and pen 4 were recorded as 85.33% and 85% respectively. Temperature, Salinity, PH, Nitrate and Phosphate were ranged 27−31oC, 35−40 ppt, 7.3−8.8, 0.25−2.5 mgL-1 and 0.38−0.44 mgL-1 respectively. The results show that, there were significant difference (p > 0.05) between Specific growth rate and stocking density. The result indicated that the specific growth rate and survival rate were higher in pen 1 and pen 2 than pen 3 and pen 4 and applicable for the implementation.Item Growth Performance of Panulirus ornatus (Spiny lobster) with Three Different Feeds in Indoor Culture in Jaffna, Sri Lanka(Uva Wellassa University of Sri Lanka, 2021) Jenitha, J.; Athula, J.A.; Nirooparaj, B.Indoor fattening practices of Panulirus ornatus (spiny lobsters) operated in Jaffna, Sri Lanka practicing with typical trash fish feeding. Effect of growth was evaluated with different feeds and water quality of P. ornatus culture and suggest a proper feed among the aquafarmers for P.ornatus due to unaware about feeds. Study entailed Completely Randomized Design with three different feeds (trash fish, crab meat, and clam flesh) and three replicates, 45 wild-caught P. ornatus of mean body weight 440.91 ± 29.11 g mean carapace length 8.00 ± 0.37 cm were stocked at the rate of two per m2, cultured for 11 weeks, fresh chopped flesh fed at optimum rate of 5% of body. Water quality including temperature, pH, salinity, Dissolved Oxygen, nitrate, nitrite and total ammonia and growth performance indicators of Average Daily Weight gain (ADW), Average Daily Length gain (ADL), Specific Growth Rate (SGR), Feed Conversion Ratio (FCR) and survival rate were examined and proximate analysis was done. P. ornatus had grown best on clams which containing highest crude protein 70.26 ± 13.26% lowest fat 0.60 ± 0.18%, indicating highest SGR as 0.19 ± 0.02% where trash fish and crab fed lobsters showed lowest SGR 0.16 ± 0.02% and 0.13 ± 0.04% with the crude protein, and fat levels of 18.13 ± 4.64%, 8.58 ± 1.09% and 10.66 ± 1.77%, 1.64 ± 0.22% respectively. Highest ADW was recorded from clam fed lobsters as 0.94 ± 0.11, 0.77 ± 0.11 and 0.58 ± 0.15 g day−1 for lobsters fed with trash fish and crabs respectively. Lowest FCR of 1.42 ± 0.05 showed with clam fed lobsters, crab and trash fish fed lobsters showed relatively high FCR indicating 2.76 ± 1.37, 1.63 ± 0.37 respectively. Growth significantly (P < 0.05) affected by water quality and maximum growth occurred at 29 ˗ 30°C temperature, 0.01 ˗ 0.02 mg Lˉ1 of Ammonia, 6.5 ˗ 6.9 mg Lˉ1 of the Dissolved Oxygen levels. Survival rate was similar as 100% in all treatments. Findings show that spiny lobsters grow well when fed clams high in protein and lowest fat indicating suitability in lobster farming industry. Keywords: Panulirus ornatus; SGR; Growth performance