The Journal of Experimental Life Sciences (JELS)
Vol. 15 No. 3 (2025)

Changes in Blood Glucose and Cortisol in Nile Tilapia (Oreochromis niloticus) with Different Salinities

Satiti, Cinca Hayyu Putri (Unknown)
Faqih, Abdul Rahem (Unknown)
Mahmudi, Mohammad (Unknown)
Moehammad, Khibar Syiar (Unknown)



Article Info

Publish Date
23 Dec 2025

Abstract

Nile tilapia (Oreochromis niloticus) is a freshwater fish of high economic value that can tolerate a wide range of salinities, offering potential for the utilization of idle coastal ponds in northern Java. This study aimed to evaluate the physiological stress responses of Nile tilapia exposed to different salinity levels by measuring blood glucose levels, cortisol concentrations, and survival rates. The experiment was conducted for 28 days at the Sumberpasir Freshwater Fisheries Laboratory, Malang, using a Completely Randomized Design with four salinity treatments (0, 7, 14, and 21 ppt) in triplicate. Data on blood glucose and cortisol were analyzed using ANOVA (p < 0.05), while survival rate and water quality were analyzed descriptively. The results showed that salinity significantly affected blood glucose levels, with the highest value recorded at 21 ppt (115±39.2 mg.dL-1) and the lowest at 0 ppt (63±29.9 mg.dL-1). In contrast, cortisol levels were not significantly different among treatments, with the lowest average at 14 ppt (33.23±4.17 ng.mL-1). The highest survival rate was found at 0 and 7 ppt (100%), declining to 98% and 93% at 14 and 21 ppt, respectively. It is concluded that Nile tilapia can adapt physiologically to salinity levels of up to 21 ppt, with 14 ppt being the most stable level for stress adaptation. Further study is recommended to assess long-term growth and molecular indicators supporting the development of brackish water aquaculture.

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Journal Info

Abbrev

jels

Publisher

Subject

Biochemistry, Genetics & Molecular Biology Immunology & microbiology Medicine & Pharmacology Neuroscience

Description

The Journal of Experimental Life Science (JELS) is a scientific journal published by Postgraduate School, University of Brawijaya as distribution media of Indonesian researcher’s results in life science to the wider community. JELS is published in every four months. JELS published scientific ...