Effects of salinity on histopathology of kidney in Asian sea bass (Lates calcarifer)

Present study aimed to investigate salinity effects histopathological of kidney in Asian Sea bass (Lates calcarifer). For this purpose, juvenile fish with an average weight of 34.36±0.41 g were evaluated for 30 days. After 14 days of adaptation, the experiment carried out with 4 treatments and 3 replicates including 15, 35 and 50 gram per liter and fresh water. 15 fish were randomly introduced in each of the 12 fiberglass 300-liter cylindrical tanks. Fish feeding time was twice daily. The daily water salinity decline ratio was 3 ppt. At the end of experiment, kidney tissue was sampled and the histopathological studies (except 50 ppt) showed some changes including hypertrophy and urina tract epithelial tubule, reducing the lumen and the melanomacrophage aggregation, leukocyte infiltration and necrotic cells. Overall, sea bass fish was demonstrated a suitable compatibility in response to different salinity levels. Results indicated that this species could tolerate salinity changes up to brackish water and high salinity water.