Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. J. Inland Fish. Soc. India, 47 (2) : 59-69, 2015 RESPONSE OF ANABAS TESTUDINEUS (BLOCH, 1792) TO SALINITY FOR ASSESSING THEIR CULTURE POTENTIALITY IN BRACKISH WATER INUNDATION PRONE AREAS OF INDIAN SUNDARBAN SOURABH KUMAR DUBEY, RAMAN KUMAR TRIVEDI, BIMAL KINKAR CHAND1, SANGRAM KESAHRI ROUT1 AND BASUDEV MANDAL2 Department ofAquatic Environment Management, Faculty of Fishery Sciences, West Bengal University of Animal and Fishery Sciences, Kolkata-700094, India 1 Directorate of Research, Extension & Farms, West Bengal University of Animal and Fishery Sciences, Kolkata-700037, India 2 Department of Aquaculture Management and Technology, Vidyasagar University, Midnapore, West Bengal721102, India (Received : 31.10.2015; Accepted : 23.12.2015) The present study investigated the effect of salinity on growth and survival of Anabas testudineus for assessing their culture potential in brackish water. The estimated median lethal salinity concentration of 96-hour for A. testudineus (11.74 g) was 18.86 g l-1. Based on median lethal salinity concentration, survival and growth performances were assessed at three sub-lethal salinity levels. Highest growth performances were obtained in 5 g l-1 salinity followed by 0 g l-1, 10 g l-1 and 15 g l-1 salinity. The survival rate was not hampered up to 10 g l-1 salinity. This study implies that A. testudineus can be cultured up to 15 g l-1 salinity and can be considered as an ideal species to promote in Indian Sundarban delta where brakish water intrusion is frequent phenomenon. Key words: Anabas testudineus, fish growth, salinity stress, median lethal salinity, Indian Sundarban. Introduction 2001) but there are relatively few studies on the effects of salinity on growth in stenohaline freshwater fish (Davis and Simico, 1976; Altinok and Grizzle, 2001). Growth performance studies with long-term rearing in brackish water up to the upper salinity tolerance are lacking. Therefore, it is important to understand the effect of salinity on freshwater fish species in areas where saline water inundation is a common phenomenon. Salinity is one of the most important environmental factors which influence survival, growth and distribution of many aquatic organisms (Boeuf and Payan, 2001; Kang'ombe and Brown, 2008). Salinity tolerance is an important consideration in the culture of marine and freshwater organisms providing information about basic culture requirements necessary for the species to thrive in captivity as well as potential applications for assessing the distribution of fish and their impact on ecosystems (Kilambi and Zdinak, 1980; DiMaggio et al., 2009). There are many examples of marine and euryhaline species that grow faster when reared in brackishwater (Boeuf and Payan, In recent years, climate variability manifested by sea level rise, the increased incidence of coastal flooding and tropical cyclones, which are responsible for salinity mediated water stress of freshwater fisheries in various parts of the world 59 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. DUBEY et al. ecological conditions (Amornsakun et al., 2005). Moreover, perch aquaculture nowadays takes place exclusively in freshwater, but given that perch naturally inhabit areas with various strengths of brackish water, it may be possible to utilise brackish water areas or the freshwater aquaculture areas prone to saline water inundation for perch aquaculture. The effects of salinity on growth performances remain largely unknown in perch (Overton et al., 2008). Hence, the present study was undertaken to determine salinity tolerance limit and growth performance of A. testudineus reared in different sub-lethal salinities. The results obtained from this study will be useful in assessing the resilience of this species for culture in the areas vulnerable to brackish water inundation. (Cruz et al., 2007; Badjeck et al., 2010). This picture is quite prominent in coastal areas of West Bengal, especially in the Indian Sundarban, UNESCO declared world heritage site (Chand et al., 2012a). Earthen embankments encircling the Sundarban keep the brackish water away from the island. Saline water inundation due to breach of river embankment, sea level rise and subsequent erosion coupled with frequent extreme weather events affect freshwater fish culture inside the island, which is basically freshwater ecosystem (Chand et al., 2012b). During the severe tropical cyclone Aila in 2009, a large proportion of freshwater areas of Sundarban were completely submerged in brackish water. The event brought changes in environmental parameters, specially the average surface water salinity from 13.64 ± 6.24 g l-1 to 17.08 ± 8.03 g l-1 with an increase of 25.2 % (Mitra et al., 2011). This salinity remains in inland water, rises slowly and peaks in premonsoon period. Due to salinity intrusion in freshwater aquaculture areas, many freshwater fish species are subjected to severe physiological stress and hormonal changes due to their inability to cope up with such extreme conditions (Sarma et al., 2013). In this background there is an urgent need to ascertain whether some freshwater fish can be cultured in brackish water areas. Material and methods Experimental animals and study site Healthy and active sub-adult of A. testudineus were collected from the freshwater zone (salinity constantly below 1 g l-1) and transported to NICRA climate resilient aquaculture wet laboratory of WBUAFS located at Jharkhali fish farm complex (N 22º01.219' & E 088º41.075'), eastern part of Sundarban mangrove eco-region. The fish were acclimatized to the laboratory condition in freshwater for a period of one week before commencement of experiment. Freshwater indigenous air-breathing fish, climbing perch Anabas testudineus (Bloch 1972) is a high value species unlike Tilapia in India (usually fetches 3 times higher price compared to Tilapia). It is well distributed in Indian subcontinent including Sundarban region of West Bengal state and commonly found in low lying swamps, marsh lands, lakes, canals, ponds, paddy fields, estuaries etc (Jayaram, 1981; Talwar and Jhingran, 1991). Again in homestead pond inside island farmers do freshwater polyculture. They are very hardy by nature and can tolerate extremely unfavourable Salinity tolerance test A non-renewal static toxicity bioassay was conducted in the first phase to determine median lethal salinity (MLS-5096h) for the sub-adults of A. testudineus. Median lethal salinity is defined as the salinity at which survival of test species falls to 50% in 96 h following direct transfer from freshwater to various test salinities (Watanabe et al., 1990). Initially a range finding test was done 60 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. CULTURE POTENTIALITY OF A. TESTUDINEUS Herobhanga (average salinity 24-28 g l-1). Freshwater (0 g l-1) was achieved from ground water source. The ground water was collected from a deep tube well (230 m deep), which is basically used for drinking purpose for the nearby guest house. Both the waters were collected separately in FRP (fibreglass reinforced plastic) tanks and vigorously aerated. Desired salinity (5, 10 and 15 g l-1) was made by appropriately mixing freshwater with saline water. About 30 % of water volume was renewed weekly and salinity was maintained adding freshwater or saline water wherever necessary. Fig.1. Sigmoid cumulative distribution dose response curve for A. testudineus in different salinities A total of 180 fish was distributed directly in three salinity treatment groups and reared for 60 days. A freshwater treatment (0 g l-1) was run simultaneously as control. Stocking density maintained was 15 fish / tank. Experiment was conducted in 200 l identical FRP tanks (L: W: H = 1.8: 0.8: 0.6 m) in which 150 l water volumes was maintained. For carrying out each experiment, three replicates were run simultaneously following a completely randomized design (CRD). to record mortality percentage of 0 to 100 % (Peltier and Weber, 1985). Then the test species (11.74 ± 1.38 g) were directly subjected to four different test salinities (16 to 20 g l-1) and observed for 96 h (APHA, 2012). The experimental system consisted of 10 l glass aquaria (L: W: H=30: 20: 20 cm) stocked with eight juveniles/ aquarium with three replicates. MLS-5096h was calculated by Probit method (Finney, 1971) using XLSTAT programme (Version 2015.1.01.) The median lethal concentration of salinity at the end of 96 h exposure for A. testudineus (11.74 g) was 18.86 g l-1. The precision of the test results for a typical sigmoid cumulative distribution dose response curve has been demonstrated in Fig.1. Based on MLS96h value different sub-lethal salinities were identified to assess the effect of salinity on growth performances of the fishes. Fish were fed twice a day (8 am and 4 pm) ad libitum with pelleted feed (Charoen Pokphand Group, Samut Sakhon, Thailand). The leftover food and faecal matters were removed daily by siphoning. Water quality parameters of the experimental tanks were monitored weekly. Temperature, pH, dissolved oxygen and salinity were determined directly by digital water analysis instrument (HANNA, HI 9828, Germany) while ammonianitrogen (NH3-N) and nitrate-nitrogen (NO3-N) were measured using HACH spectrophotometer (DR 2800, Germany). Experimental design of growth performance study Four different treatment groups viz., 0 g l-1 (T1), 5 g l-1 (T2), 10 g l-1 (T3) and 15 g l-1 (T4) were maintained to access the effects of salinity on survival and growth of the fishes. For this natural saline water was collected from nearby tidal river All individuals from each treatment were sampled weekly. Body weight was measured to assess the 61 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. DUBEY et al. growth while mortality was noted daily. Body weight was measured to the nearest gram by portable electronic balance (Kern EMB 500-1; D= 0.1g). The growth rates were calculated in terms of specific growth rate (SGR; %/day), body weight gain (BWG %), as the percentage increase in body weight per day over any given time interval (Brown, 1957) by using the following formulae: and Ayhan, 2010). Signs like aggression, jumping, frequent surface bottom movements (FSBM), sluggish and swirling movements (SSM), erratic swimming, opercula movement, excessive mucus secretion (EMS) were documented in first 24 hours (Hassan et al., 2013). Analysis of experimental data The data obtained in the present investigations were subjected to one-way analysis of variance using statistical software Medcalc® version 12.7.0. (MedCalc Software bvba, Ostend, Belgium). Tukey (HSD) test was used to determine the differences among the means. Significant differences are stated at P < 0.05 level unless otherwise noted. SGR (% / day) = (Ln Wf - LnWi) / ∆ t) *100, Where LnW represents the natural log of individual wet weight (g); Wf is the final wet weight of fish, Wi the initial wet weight, ∆ t is the durations. BWG (%) = (Final Weight - Initial Weight /Initial Weight) *100 Survival (%) = (Number of fish survived at end of experiment / Number of fish stocked) * 100 Results Water quality Behaviour observation Mean values and ranges of water quality parameters over 60 days rearing of A. testudineus are presented in Table 1. There were no significant differences (P > 0.05) in water quality parameters among all the treatments. The abnormal behaviour was observed by visual assessment. Behavioural responses of fish such as convulsions, equilibrium status, hyperactivity, swimming etc were observed (Rand, 1985; Aysel Table 1. Mean values and ranges (in parenthesis) of water quality parameters in the rearing tanks of A. testudineus for a period of 60 days Salinity treatments -1 Parameters 0 g l (T1) 5 g l-1 (T2) 10 g l-1 (T3) 15 g l-1 (T4) Water temperature 28.50 ± 1.89a 28.57 ± 2.34a 28.17 ± 2.16a 28.61 ± 2.00a (ºC) (26.5- 31.32) (26.08-31.56) (26.44-31.34) (26.48-31.37) Dissolved oxygen 5.95 ± 0.40a 6.01 ± 0.39a 5.98 ± 0.38a 6.13 ± 0.42a -1 (mg l ) (5.31-6.5) (5.39-6.5) (5.21-6.55) (5.5-6.72) pH 8.37 ± 0.29a 8.29 ± 0.33a 8.23 ± 0.32a 8.12 ± 0.34a (7.89-8.62) (7.67-8.7) (7.89-8.72) (7.77-8.56) Ammonia-Nitrogen 0.17 ± 0.10a 0.19 ± 0.09a 0.22 ± 0.05a 0.22 ± 0.01a (mg l-1) (0.01-0.31) (0.01-0.32) (0.12-0.26) (0.01-0.34) Nitrate-Nitrogen 0.08 ± 0.05a 0.09 ± 0.04a 0.10 ± 0.05a 0.11 ± 0.07a (mg l-1) (0.02-0.14) (0.03-0.16) (0.02-0.18) (0.01-0.23) Data are presented as Mean ± SD of three replicates. Different superscripts in same row were significantly different (P<0.05) 62 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. CULTURE POTENTIALITY OF A. TESTUDINEUS Table 2. Initial weight final weight (g), weight gain (g), specific growth rate (% /day) and body weight gain (%) of A. testudineus reared in different salinities for 60 days Salinity treatments -1 -1 Variables 0 g l (T1) 5 g l (T2) 10 g l-1 (T3) 15 g l-1 (T4) Initial weight (g) 11.61 ± 0.31 13.51 ± 0.64 14.16 ± 0.61 14.47 ± 0.81 Final weight (g) 14.59 ± 0.01 16.60 ± 0.05 16.57 ± 0.28 16.72 ± 0.32 Weight gain (g) 2.85 ± 0.17ab 3.59 ± 0.19a 2.40 ± 0.37b 2.24 ± 0.29b Specific growth rate (% /day) 0.37 ± 0.02a 0.42 ± 0.02a 0.26 ± 0.03b 0.24 ± 0.03b Body weight gain (%) 24.32 ± 2.00ab 27.64 ± 1.98a 18.31 ± 2.71bc 15.54 ± 2.62c Data are presented as Mean ± SD of three replicates. Different superscripts in same row were significantly different (P<0.05) Survival and growth performance The mean water temperatures in T1, T2, T3, and T4 were 28.50, 28.57, 28.17 and 28.61 ºC respectively. Mean dissolved oxygen levels were 5.95, 6.01, 5.98 and 6.13 mg l-1 in T1, T2, T3, and T4 respectively. Mean pH values showed a decreasing trend with a value of 8.37, 8.29, 8.23 and 8.12 in T1, T2, T3, and T4 respectively. Ammonia-nitrogen (NH3-N) and nitrate -nitrogen (NO3--N) contents in T1, T2, T3, and T4 showed an increasing trend (0.17, 0.19, 0.22 and 0.22 mg l-1 respectively and 0.08, 0.09, 0.10 and 0.11 mg l-1 respectively) but variations among the treatments were not significant (P > 0.05). The growth performances of A. testudineus in different salinity treatments are summarised in Table 2. Weekly increment of body weight (Mean ± SD) of A. testudineus in different salinities is depicted in Fig. 2. Significant differences in total weight gain (F 3, 7 = 13.01, P=0.003; R2= 0.84), specific growth rate (SGR) (F 3, 7 = 16.52, P=0.001; R2= 0.87) and percentage body weight gain (BWG %) (F 3, 7 = 18.40, P=0.01; R2= 0.88) of A. testudineus were observed in different salinity treatment. At the end of 60 days culture period, fish exhibited the lowest SGR at 15 g l-1 (0.24 %/ day) and significantly highest (P<0.05) at 5 g l-1 (0.42 %/ day). However, SGR between 0-5 g l-1 and 10-15 g l-1 did not differed significantly (P>0.05). This growth trend was also similar in case of the BWG (%) which was significantly highest in 5 g l-1 (P<0.05) followed by 0 g l-1, 10 g l-1 and 15 g l-1, but differences among them were not significant (P>0.05). The fish demonstrated lowest total weight gain (2.23 g) at 15 g l-1 and significantly highest (3.69 g) (P<0.05) in 5 g l-1 but differences in weight gain between 0 g l-1, 10 g l-1 and 15 g l-1 were not significant (P>0.05) (Table 2). After 60 days of rearing period, survival rate of A. testudineus was not hampered up to 10 g l-1 salinity but did not show remarkable variations. Survival rate in corresponding experiment was 100, 100, 100, and 97 % in T1, T2, T3, and T4 respectively. Fig. 2. Weekly increment of body weight (Mean ± SD) of A. testudineus in different salinities. 'W' denotes weeks 63 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. DUBEY et al. Behaviour observation study also indicated that the median lethal salinity value of A. testudineus is high (18.86 g l-1) and it supports that the species exhibits good tolerance to abrupt changes in salinity. Survival rate of sub-adult A. testudineus was not affected up to 10 g l-1 salinity in the present study. In an early study, Bersa (1997) showed that A. testudineus fingerlings (6-10 g) could withstand 2.5-10 g l-1 seawater without mortality. Similarly Mansuri et al. (1979) observed that indigenous freshwater fish Channa punctatus could thrive well in 10 g l-1 seawater for indefinite period and mortality started beyond that. Low survival rates of Clarias batrachus at higher salinity were reported by Sarma et al. (2013) and in Rainbow trout (McKay and Gjerde, 1985). It was also reported that Indian major carp Catla catla and Labeo rohita fry and fingerlings could tolerate 8 g l-1 salinity without mortality (Ghosh et al., 1973) but survival gradually decreased with increase of salinity. No high level stressful behavioural symptoms like agitated behaviour (aggression, jumping, FSBM, erratic swimming), respiratory disturbance (opercula movement, EMS) and abnormal nervous behaviour (SSM, motionless state) were observed up to 10 g l-1 but fishes expressed frequent surface bottom movements (FSBM) and fast opercula movement immediately exposed to 15 g l-1. Erratic swimming and mucus secretion was observed at moderate level in increasing salinity. Discussion Water quality The water quality parameters during rearing period were relatively stable. The temperature, pH, dissolved oxygen of the experimental setting were within the acceptable range for fish culture that agrees well with the findings of Boyd et al. (1982), Wahab et al. (1995) and Chakraborty et al. (2005). Nitrogenous compounds like ammonianit rogen (NH 3-N) and nitrate-nit rogen (NO3-N) showed an increasing trend in higher salinity but within the acceptable range. Freshwater teleosts are generally ammonotelic and they may become ureotelic when an impairment of ammonia excretion occurs (Ip et al., 2001; Wright, 2007). Rejitha et al. (2009) argued that A. testudineus can rely on ureogenesis during exposure to ascending ambient salinity. It is likely that the higher plasma urea in freshwater fish due to an augmented ureogenesis may be a consequence of an impaired ammonia excretion upon salinity challenge. Growth of A. testudineus reared in different salinities was improved at mild brackishwater, in this case 5 g l-1. A three weeks growth trial of pikeperch (Sander lucioperca) and perch (Perca fluviatilis) in the Baltic Sea region revealed an optimal growth rate at 5g l-1 at 16-25 °C (Ložys 2004). Growth of A. testudineus fry could not be hampered when exposed to 7.5 to 10 g l-1 seawater (Bersa 1997). According to Woo and Kelly (1995), in freshwater condition fishes spend a certain amount of energy to compensate for salt lost through passive diffusion, providing mild brackishwater reduces energy expenditure and consequently promotes growth. Consistent with the present study, Altinok and Grizzle (2001) showed that two stenohaline freshwater species, the channel catfish (Ictalurus punctatus) and the gold fish (Carassius auratus) have the highest specific growth rates, most efficient feed conversion ratio and energy absorption efficiency in mild brackishwater. This was also recorded for Survival and growth performance A. testudineus occurs naturally in estuarine areas of West Bengal and adapted to an environment where salinity levels vary constantly. Results of this 64 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. CULTURE POTENTIALITY OF A. TESTUDINEUS common carp, Cyprinus carpio (Wang et al., 1997). Similar results were also observed in European bass, Dicentrarchus labrax (Dendrinos and Thorpe, 1985), juvenile croaker, Micropogonias furnieri (Abud, 1992), silver perch, Bidyanus bidyanus (Kibria et al., 1999; Guo et al., 1993). Moreover, Konstantinov and Martynova (1993) experimenting with freshwater species showed that common carp (Cyprinus carpio), grass carp (Ctenopharyngodon idella) and juvenile Russian sturgeon (Acipenser guldenstaedti) demonstrated considerably increased growth rate at 2 g l-1 salinity. In fish, often in fact, a better growth rate is observed in intermediary salinity conditions, i.e. in brackishwater 2-10 g l-1, but this is often, not systematically, correlated with a lower standard metabolic rate (Morgan and Iwama, 1991; Swanson, 1998; Plaut, 1999). et al., 2001). The low appetite of the fish was probably induced by a decreased sensitivity of the olfactory nerves to amino acids, reducing the stimulus to eat (Shoji et al., 1996). In addition, lower protein digestibility at high salinities may be related to shorter retention time of food in the gut and increased drinking rates for osmoregulation that alters body growth (Ferraris et al., 1986). Optimal salinities for growth of freshwater fish appear to vary according to individual species, life stage and seasonal depended cues. The discrepancy may result from differences in experimental design, feed type, temperature optima and age of the fish, genetic stock and genetic differences between distinct populations (Overton et al., 2008). Morgan and Iwama (1991) described differences in growth responses to increasing salinity between freshwater and migrating strains of rainbow trout Oncorhynchus mykiss. Chervinski (1984) has stated that there are two types of freshwater fish, so called primary and secondary freshwater fish. The primary freshwater fish which migrate entirely in freshwater such as Claridae and Cyprinidae are not able to tolerate salinities higher than 9.8 g l-1. The effects of salinity on growth are complex and vary among species (Iwama, 1996). It is widely accepted that rearing of fish near their iso-osmotic point has an energy saving effect (Gaumet et al., 1995; Boeuf and Payan, 2001). Reduction of growth in elevated salinity results from osmotic disturbances led to increased energy expenditure, protein sparing and depletion of carbohydrate and lipid reserves, which in turn affects biomass. Fish exposed to increased salinity are likely to face a conflict between the mechanisms of salt uptake and nutrient uptake in the gut. Although the present study did not analyze feeding efficiency and conversion ratio, but it has been observed that increased salinity stress led to reduced appetite. Fish consumed less feed when exposed to higher salinity. This has a practical implication for fish farmers to reduce the feeding rates as salinity increases after saltwater intrusion. Reductions in growth due to decreased food intake in increasing salinity have been reported in several species (Ferraris et al., 1986; Boeck et al., 2000; Imsland Behaviour observation A. testudineus did not show any remarkable stressful sign upto 10 g l-1 indicated that fish remain unaffected physiologically up to 10 g l-1. Erratic swimming was noted moderately after immediate exposure in 15 g l-1 depicted the fish were approaching towards maximum tolerance limit (Lawson and Anetekhai, 2011). Respiratory distress like increased opercula movement in higher salinity level may be due to excessive mucus secretions. Mucus in the gills reduces respiratory activity in fishes and unable to perform gaseous exchange (Konar, 1970). Exposure to high salinity level primarily increase the opercular movement 65 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. DUBEY et al. and Basanti Blocks of Indian Sundarban". The aut hors are indebted to the Sundarban Development Board, Govt. of West Bengal for sharing their field experimenting facilities. The authors are thankful to Mr. Sudan Roy for field assistance. The authors are also indebted to anonymous reviewers for their constructive comments and suggestions. of fish to cope up with stress condition but due to excessive mucus secretion and further prolonged exposure period, the opercular movement frequency progressively decreased. Then the fishes swam on the water surface in order to increase oxygen intake (Iwama et al., 1997; Soares, 2006; Hassan et al., 2013). Conclusion References The results of the present experiment indicated that salinity plays a significant role for the culture of freshwater climbing perch A. testudineus and the species showed satisfactory growth and survival at salinity range of 5-15 g l-1. In view of the current and future climate variables, more coastal areas of India are going to be vulnerable to brackish water inundation. Under such scenario, A. testudineus can be considered as an ideal species to promote in Indian Sundarban and other tropical deltas where brackish water intrusion is frequent phenomenon. This study will help farmers to make a decision on species selection that can facilitate decrease risks associated with salt water inundation for short periods. The outcome can be utilized in farm site selection and salinity maintenance to maximize commercial productivity in coastal inundation prone area. However, standardization of culture technique through farmers' trials and further studies to understand the ecosystem-based adaptation processes at higher salinity level is recommended. Abud, E. O. A. 1992. Effects of salinity and weight on routine metabolism in the juvenile croaker, Micropogonias furnieri (Desmarest 1823). Journal of Fish Biology, 40: 471-472. Altinok, I. and Grizzle, J. M. 2001. Effects of brackish water on growth, feed conversion and energy absorption efficiency by juvenile euryhaline and freshwater stenohaline fishes. Journal of Fish Biology, 59: 1142-1152. Amornsakun,T., Sriwatana, W. and Promkaew, P. 2005. Some aspects in early life of climbing perch, Anabas testudinneus larvae. Songklanakarin Journal of Science and Technology, 27: 403-418. Aysel, C. K. B. and Ayhan, O. 2010. Acute toxicity and histopathological effects of sublethal fenitrothion on Nile tilapia, Oreochromis niloticus. Pesticide Biochemistry and Physiology, 97: 32-35. Badjeck, M. C., Allison, E. H., Halls, A. S. and Dulvy, N. K. 2010. Impacts of climate variability and change on fishery based livelihoods. Marine Policy, 34: 375-383. Besra, S. 1997. Growth and Bioenergetics of Anabas testudineus (Bloch). Narendra Publishing House, New Delhi, India. 139 p. Acknowledgements The authors are grateful to Indian Council of Agricultural Research (ICAR); New Delhi for the financial assistance granted for this study through NICRA (National Initiatives on Climate Resilient Agriculture) project entitled "Development of Climate Resilient Aquaculture Strategies for Sagar Boeck, G. D., Vlaeminck, A., Linden, A. V. and Blust, R. 2000. The energy metabolism of common carp (Cyprinus carpio) when exposed to salt stress: An increase in energy expenditure or effects of starvation? Physiological and Biochemical Zoology, 73 (1): 102111. 66 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. CULTURE POTENTIALITY OF A. TESTUDINEUS Boeuf, G. and Payan, P. 2001. How should salinity influence fish growth? Comparative Biochemistry and Physiology Part C: Toxicology and Pharmacology, 130 : 411-423. Dendrinos, P. and Thorpe, J. P. 1985. Effects of reduced salinity on growth and body composition in the European bass, Dicentrarchus labrax (L.). Aquaculture, 49: 333-358. Boyd, C. E. 1982. Water quality management for pond fish culture. Elsevier Scientific Publishing Company, New York. 318p. DiMaggio, M. A., Cortney, L. O. and Denise Petty, B. 2009. Salinity tolerance of the Seminole killifish, Fundulus seminolis, a candidate species for marine baitfish aquaculture. Aquaculture, 293: 74-80. Brown, M. E. 1957. Experimental studies on growth, pp 361-400. In: Brown, M. E. (ed), The physiology of Fishes, volume-I. Academic Press, New York. Ferraris, R. P., Catacutan, M. R., Mabelin, R. L. and Jazul, A. P. 1986. Digestibility in milkfish, Chanos chanos (Forsskal): affects of protein source, fish size and salinity. Aquaculture, 59: 93-105. Chakraborty, B. K., Miah, M. I., Mirza, M. J. A. and Habib, M. A. B. 2005. Growth, yield and returns to Puntius sarana (Hamilton) Sharpunti, in Bangladesh under semi intensive aquaculture. Asian Fisheries Science, 18: 307322. Gaumet, F., Boeuf, G., Severe, A., Le Roux, A. and MayerGostan, N. 1995. Effects of salinity on the ionic balance and growth of juvenile turbot. Journal of Fish Biology, 47: 865-876. Chand, B. K., Trivedi, R. K., Biswas, A., Dubey, S. K. and Beg, M. M. 2012a. Study on impact of saline water inundation on freshwater aquaculture in Sundarban using risk analysis tools. Exploratory Animal Medical Research, 2: 170-178. Ghosh, A. N., Ghosh, S. R. and Sarkar, N. N. 1973. On the salinity tolerance of fry and fingerlings of Indian major carps. J. Inland Fish. Soc. India, 5: 215-217. Guo, R., Mather, P. and Capra, M. F. 1993. Effect of salinity on the development of silver perch (Bidyanus bidyanus) eggs and larvae. Comparative Biochemistry and Physiology Part A: Physiology, 104: 531-535. Chand, B. K., Trivedi, R. K. and Dubey, S. K. 2012 b. Climate change in Sundarban and adaptation strategy for resilient aquaculture, pp 116-128. In: Sinha, A., Katiha, P. K. and Das, S. K. (eds), CIFRI Compendium on Sundarban, Retrospect and Prospects. Central Inland Fisheries Research Institute, Kolkata, India. Hassan, M., Zakariah, M. I., Wahab, W., Muhammad, S. D. and Idris, N. 2013. Histopathological and Behavioral Changes in Oreochromis sp after Exposure to Different Salinities. Journal of Fisheries and Livestock Production, 1: 103. http://dx.doi.org/10.4172/23322608.1000103 Chervinski, J. 1984. Salinity tolerance of young catfish, Clarias lazera. Journal of Fish Biology, 25: 147-1499. Cruz, R.V., Harasawa, H., Lal, M., Wu, M., Anokhin, Y., Punsalmaa, B., Honda, Y., Jafari, M., Li, C. and Huu Ninh, N. 2007. Asia. Climate Change 2007: Impacts, Adaptation and Vulnerability, pp 469-506. In Parry, M.L., Canziani, O.F., Palutikof, J.P., vander Linden, P.J. and Hanson, C.E. (eds.), Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK. Imsland, A. K., Foss, A., Gunnarsson, S., Berntssen, M. H. G., FitzGerald, R., Bonga, S. W., Ham, E.V., Nævdal, G. and Stefansson, S. O. 2001. Interaction of temperature and salinity on growth food conversion in juvenile turbot, Scophthalmus maximus. Aquaculture, 198: 353367. Ip, Y. K., Chew, S. F. and Randall, D. J. 2001. Ammonia toxicity, tolerance and excretion, pp 109-148. In: Wright, P.A. and Anderson, P.M. (eds), Fish Physiology vol. 20. Academic Press, New York. Iwama, G. K. 1996. Growth of salmonids, pp 467-516. In: Pennell, W. and Barton, B.A. (eds), Principles of Davis, K. B. and Simico, B. A. 1976. Salinity effects on plasma electrolytes of channel catfish, Ictalurus punct. Journal of the Fishery Research Board of Canada, 33: 741-746. 67 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. DUBEY et al. Channa punctatus Bloch. 1. Salinity tolerance, tissue water and mineral levels. J. Inland Fish. Soc. India, 11: 74-82. Salmonid Culture. Elsevier Scientific Publishing Company Amsterdam, Netherlands. Iwama, G. K., Takemura, A. and Takano, K. 1997. Oxygen consumption rates of tilapia in freshwater, seawater, and hyper saline seawater. Journal of Fish Biology, 51: 886894. McKay L. R. and Gjerde, B. 1985. The effect of salinity on growth of rainbow trout. Aquaculture, 49: 325-333. Mitra A, Halder, P. and Banerjee, K. 2011. Changes of selected hydrological parameters in Hoogly estuary in response to severe tropical cyclone (Aila). Indian Journal of Geo-marine Sciences, 40 (1): 32-36. Jayaram, K. C. 1981. The Freshwater Fishes of India, Pakistan, Bangladesh, Burma and Sri Lanka - A Handbook. Zoological Survey of India, Calcutta, India. 475p. Kang'ombe, J. and Brown, J. A. 2008. Effect of Salinity on growth, feed utilization, and survival of Tilapia rendalli under laboratory conditions. Journal of Applied Aquaculture, 20 (4):256-271. Morgan, J. D. and Iwama, G. K. 1991. Effects of salinity on growth, metabolism, and ion regulation in juvenile rainbow and steelhead trout (Onchorynchus mykiss) and fall Chinook salmon (Onchorynchus tshawytscha). Canadian Journal of Fisheries and Aquatic Sciences, 48: 2083-2094. Kibria, G., Nugegoda, D., Fairclough, R. and Lam, P. 1999. Effect of salinity on growth and nutrient retention in silver perch, Bidyanus bidyanus (Mitchell 1838) (Teraponidae). Journal of Applied Ichthyology, 15: 132134. Overton J. L., Bayley, M., Paulsen, H. and Wang, T. 2008. Salinity tolerance of cultured Eurasian perch, Perca fluviatilis L.: Effects on growth and on survival as a function of temperature. Aquaculture, 277: 282-286. Kilambi, R. V. and Zdinak, A. 1980. The effect of acclimation on the salinity tolerance of grass carp, Ctenopharyngodon idella (Cuv. and Val.). Journal of Fish Biology, 6:171-175. Plaut, I. 1999. Effects of salinity acclimation on oxygen consumption in the freshwater blenny, Salaria fluiatilis, and the marine peacock blenny, S. pavo. Marine and Freshwater Research, 50: 655-659. Konar, S. K. 1970. Nicotine as a fish poison. Progressive Fish Culturist, 32: 103- 104. Rand, G. M. 1985. Behavior, pp 221-256. In: Rand, G.M. and Petrocelli, S.R. (eds), Fundamentals of Aquatic Toxicology: Methods and Applications. Hemisphere Publishing Corporation, Washington. Konstantinov, A. S. and Martynova, V. V. 1993. Effect of salinity fluctuations on energetics of juvenile fish. Journal of Ichthyology, 33: 161-166. Rejitha, V., Peter, V. S. and Peter, M. C. S. 2009. Shortterm salinity acclimation demands thyroid hormone action in the climbing perch Anabas testudineus Bloch. Journal of Endocrinology and Reproduction, 13: 6372. Lawson, E. O. and Anetekhai, M. A. 2011. Salinity tolerance and preference of hatchery reared Nile Tilapia, Oreochromis niloticus (Linnaeus1758). Asian Journal of Agricultural Sciences, 3: 104-110. Sarma, K., Prabakaran, K., Krishnan, P., Grinson, G. and Kumar, A. A. 2013. Response of a freshwater airbreathing fish, Clarias batrachus to salinity stress: an experimental case for their farming in brackishwater areas in Andaman, India. Aquaculture International, 21:183196. Shoji, T., Fujita, K. I., Furihata, E. and Kurihara, K. 1996. Olfactory responses of a euryhaline fish, the rainbow Ložys, L. 2004. The growth of pikeperch (Sander lucioperca L.) and perch (Perca fluviatilis L.) under different water temperature and salinity conditions in the Curonian Lagoon and Lithuanian coastal waters of the Baltic Sea. Hydrobiologia, 514: 105-113. Mansuri, A., Bhatt, V. and Bhatt, N. 1979. Studies on effects of salinity changes on freshwater murrels, 68 Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. CULTURE POTENTIALITY OF A. TESTUDINEUS trout: adaptation of olfactory receptors to sea water and salt dependence of their responses to amino acids. Journal of Experimental Biology, 199:303-310. common carp, Cyprinus carpio (L), of the pond ecology and growth of fish in polyculture. Aquaculture Research, 26: 619-628. Soares, M. G. M., Menezes, N. A. and Junk, W. J. 2006. Adaptations of fish species to oxygen depletion in a central Amazonian floodplain lake. Hydrobiologia, 568: 353-367. Wang, J. Q., Lui, H., Po, H. and Fan, L. 1997. Influence of salinity on food consumption, growth and energy conversion efficiency of common carp (Cyprinus carpio) fingerlings. Aquaculture, 148: 115-124. Woo, N.Y.S. and Kelly, S. P. 1995. Effects of salinity and nutritional status on growth and metabolism of Spams sarba in a closed seawater system. Aquaculture, 135: 229-38. Swanson, C. 1998. Interactive effects of salinity on metabolic rate, activity, growth and osmoregulation in the euryhaline milkfish Chanos chanos. Journal of Experimental Biology, 201: 3355-3366. Wright, P. A. and Wood, C. M. 1985. An analysis of branchial ammonia excretion in the freshwater rainbow trout: effects of environmental pH change and sodium uptake blockage. Journal of Experimental Biology, 114: 329-353. Talwar, P. K. and Jhingran, A. G. 1991. Inland Fishes of India and Adjacent Countries, 1st Edn. Oxford and IBH Publishing Pvt. Ltd, New Delhi, India. Wahab, M. A., Ahmed, Z. F., Islam, M. A. and Rahmatullah, S. M. 1995. Effect of introduction of 69