Main Article Content
Osmotic response of a cichlid fish, Etroplus suratensis collected from two different sites of Ashtamudi lake (Ramsar Site) was observed by deploying the activity of branchial Na+-K+/ATPase enzyme. Of the two sites selected for the study, viz. Munrothuruthu (Site I) and Mukkad (Site II), marked variations in the activity of the enzyme under laboratory acclimatized saline conditions was observed. It is suggested that fish inhabiting Site I experienced a fresh water habitat as the River Kallada pours its water into this site. Fishes from Site II, located near the bar mouth and exposed to the influx of sea water, are always facing a contaminated environment owing to the discharge of domestic wastes and oil by-products discharged from the mechanised vessels harbouring Neendakara estuary. The results based on data collected from Site I fish exhibited less tolerance to varied saline conditions whereas Site II fish survived at almost all changes in salinity.
Hasanuzzaman M, Nahar K, Alam MM. Potential use of Halophytes to remediate Saline Soils, Biomed Research International. 2014.
[Article ID 589341]
Küçük S, Karul A, Yildirim S, Gamsiz K. Effects of salinity on growth and metabolism in blue Tilapia (Oreochromis aureus), African Journal of Biotechnology. 2013;12:2715-2721.
Handel SO, Berge A, Bjornsson B, Stefansson SO. Effect of temperature and salinity on osmoregulation and growth of Atlantic salmon (Salmo salar L.) smolts in seawater. Aquaculture. 1998;168:289-302.
Kulac B, Atli G, Canli M. Response of ATPases in the osmoregulatory tissues of freshwater fish, Oreochromis niloticus exposed to copper in increased salinity, Fish Physiology & Biochemistry. 2013;39(2):391–401.
Wood CM, Bergman HL, Bianchini A. Transepithelial potential in the Magadi tilapia, a fish living in extreme alkalinity. Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology. 2012;188(2):247–258.
Evans DH, Piermarini PM, Choe KP. The multifunctional fish gill: dominant site of gas exchange, osmoregulation, acid-base regulation and excretion of nitrogenous waste, Physiological Reviews. 2005;85 (1):97–177.
Roshni K, Renjithkumar CR, Kurup BM. Length‐weight relationship of two cichlid fish species, Etroplus suratensis (Bloch, 1790) and Etroplus maculatus (Bloch, 1795) from Lake Vembanad, Kerala, India. Journal of Applied Ichthyology. 2016;32(6):1308-1309.
Kidder III GW, Petersen CW, Preston RL. Energetics of osmoregulation: II. Water flux and osmoregulatory work in the euryhaline fish, Fundulus heteroclitus. Journal of Experimental Zoology, Part A. 2006;305:318-327.
Nordlie FG. Environmental influences on regulation of blood plasma serum components in teleost fish: a review. Reviews in Fish Biology and Fisheries. 2009;19:481-564.
Yang FY, Li XJ, Zhao CS, Chen Y. Prawn adaptability to saline-alkali soda lakes of northeast China, Chinese Journal of Eco-Agriculture. 2007;15(5):115–119.
Zhao F, Zhuang P, Zhang LZ. The influence of salinity acclimation on activity of Na+/K+-ATPase in branchial epithelium, concentration of ions and osmolarity in serum of Acipenser schrenckii, Journal of Fisheries of China. 2007;30(4):444–449.
Caberoy NB, Quinitio GF. Changes in Na+-K+-ATPase activity and gill chloride cell morphology in the grouper Epinephelus coioides larvae and juveniles in response to salinity and temperature, Fish Physiology & Biochemistry. 2000;23(1):83–94.
Sreejith P, Beyo RS, Prasad G, Sunny F, Oommen OV. Thyroid status alters gill ionic metabolism and chloride cell morphology as evidenced by scanning electron microscopy in a teleost Anabas testudineus (Bloch): Short and long term in vivo study. Indian Journal of Experimental Biology. 2007;45 (12),1015–1021.
Jiang QL, Lin YH, Wang XH, Liu B. Effect of NaHCO3 on growth and osmoregulation of Chalcalbumus chalcoidesaralensis. Journal of Jilin Agricultural University. 2008;30(1): 106–110.
Bonting SL. Sodium–potassium activated adenosine triphosphatase and cation transport. In Membranes and Ion Transport, (ed. E. E. Bittar). New York: Wiley. 1970;1:257–363.
Lowry OH, Rosebrough NJ, Farr AL, Randall RJ. Protein measurement with the Folin phenol reagent. Journal of Biological Chemistry. 1951;193(1):265–75.
Cramér, Harald. Mathematical Methods of Statistics. Princeton: Princeton University Press. 1946;282.
Jayewardena JMCK, Attygalle MVE. Osmoregulation of some fishes from the Bolgoda estuary. Vidyodaya J. of Sci. 1999; 8:63-74.
Vonck APMA,Wendelaar Bonga SE, Flik G. Sodium and calcium balance in Mozambique tilapia, Oreochromis mossambicus, raised at different salinities, Comp. Biochem. Physiol. A: Mol. Integr. Physiol. 1998;119: 441-449.
Sterzelecki FC, Rodrigues EB, Fanta EA, Ribeiro CAO. The effect of salinity on osmoregulation and development of the juvenile fat snook, Centropomus parallelus (POEY), Braz. J. Biol. 2013;73(3):609-615.
Lee TH, Hwang PP, Shieh YE, Lin CH. The relationship between ‘deep-hole’ mitochondria-rich cells and salinity adaptation in the euryhaline teleost, Oreochromis mossambicus, Fish Physiol. Biochem. 2000;23:133-140.