Ecology, Environment and Conservation Paper

Vol 29, Issue 1, 2023; Page No.(204-212)

SALINITY TOLERANCE AND SURVIVAL OF AN INDIAN MAJOR CARP,CIRRHINUSMRIGALA(MRIGAL): FEASIBILITY ASSESSMENT FORREARING IN INLAND SALINE WATER

Arockia Sharmila S., Abhishek Srivastava and Sachin Onkar Khairnar

Abstract

An experimental trial was conducted in triplicate to determine the effect of different salinity levels 0 (SA0),2(SA2), 4(SA4), 6(SA6), 8(SA8) and 10 (SA10) ppt on survival, behaviour, and morphological changes inmrigal, Cirrhinusmrigala fingerlings during short-term rearing in inland saline water in glass aquaria for 10days. Healthy fingerlings (average length-11.18 cm, average weight-11.05 g) of mrigal, procured from theInstructional cum Research Farm, College of Fisheries, were conditioned for one week at 0 ppt (freshwater)in FRP pools and conditioned fingerlings were gradually acclimated to varying salinities by raising thesalinity by 1 ppt hourly and then stocked into glass aquaria of respective salinity levels @ 10 fingerlingsaquarium-1. Predetermined salinity levels and the water level were maintained in all the treatments andfish were fed with pelleted feed (crude protein 26.12%) @ 0.5% of fish body weight, once a day, as sustenanceration throughout the experimental period. The results indicated that all the water quality parameters,except temperature, varied significantly (P0.05) across treatments. Furthermore, no fishmortality occurredup to 6 ppt salinity during the experiment. In contrast, survival rates were 93.33% and 86.67% at 8 and 10ppt salinity, respectively at the termination of the experiment. Normal swimming and feeding (feed intake)behaviour were recorded up to 6 ppt, whereas no adverse morphological changes were observed in fishduring the tolerance test in all the treatments. From the above results, it can be concluded that mrigal, C.mrigala can tolerate salinity up to 6 ppt during short term (10 days) rearing in inland saline water.