Effects of dietary inclusion of zeolite (Clinoptilolite) on histopathology of some tissue of tilapia (Oreochromis niloticus) infected by Aeromonas hydrophila

This study is based on the observation of protective effects in tissues and organs of the Aeromonas hydrophila injected Tilapias (Oreochromis niloticus) that are given zeolites by adding to their food between August 2008-March 2009. In the experiment, 1.9x106 CFU/ml level bacteria is given intraperitoneally injected to 36 fishes. After the injection, the fishes are observed for 21days. In the 7th, 14th and 21st days, gill, kidney and liver examples are taken from fishes and organ damages caused by bacteria are observed from these. It is observed that the feeding added zeolites has less deformations while the feeding without zeolites has more deformation. Besides it is seen in macroscobic observations; in the fish groups that took zeolites addition, there has been no decomposition on outer view. Additionally in zeolites sustained groups there has been positive scale changes in color compositions; it?s not seen thickness caused by stress. When compared to control groups, it?s seen that pathology occured by bacteria is delayed in macroscobic observations of zeolite, but in microscobic observations there is not any effect against tissue damage.Key words: Tilapia, Zeolite, Histopathology, Aeromonas hydrophila