Evaluation of sublethal salinities stress on growth performance, survival and behavioral aspects of Catla catla (Hamilton, 1822) under inland saline water

Abstract

An experiment was carried out to understand the salinity tolerance and growth performance of Catla catla (Hamilton, 1822) under inland saline aquaculture at different salinities. In the beginning of the experiment salinity tolerance studies was conducted to understand the behavior of the fish for a period of 96 hr. using LC50 assay at different salinities viz.0 (control),5 (T1), 10 (T2), 15(T3), and 20 (T4)ppt respectively. The LC50 values was calculated using probit analysis. The calculated value of LC50 assay was 7.25 ppt, based on that a 90 days experiment was designed at different salinities (ppt) viz. control (0), T1 (2), T2 (4) T3(6) and T4 (8) respectively in triplicates, following a CRD design, to assess the growth performance and survival of Catla spp. under inland saline aquaculture. During the experiment the salinities (0 ppt to 8 ppt were increased in a phase manner (explained in material & methods). The observed results show that the overall growth performance (SGR, PER, FER, ABWG) was found better in control followed by T1, T2, T3 and T4 respectively. Similarly, FCR and PER showed an increasing and decreasing trend respectively with the salinity. The survival percent was found in the range from 70-100% and showed a decreasing trend with increasing salinities. The present study suggests that Catla spp. can tolerate a salinity up to 8 ppt further, the inference from the present investigation revealed that the better growth and survival of Catla catla fingerlings can be obtained up to a salinity levels of 4 ppt without compromising significantly in growth performance and survival respectively. The present studies may be helpful to utilizing the unattended low saline inland areas for the culture of Catla spp. in the era of global warming and contribute in climate resilient aquaculture.