Abstract This study was designed to evaluate the tolerance of Clarias gariepinus juveniles to a gradual and abrupt increase in salinity over time. To this effect, C. gariepinus juveniles were exposed to three salinity incremental protocols namely 1 g L−1 day−1, 5 g L−1 day−1, and 10 g L−1 day−1. Changes in the hematological parameters and the gill histology of fish were analyzed to determine the impact of osmotic stress on the health status of the fish and its osmoregulatory ability.
