Pathomorphological Changes in Various Organs of Experimentally Induced Salmonellosis in Mice

In the study, a total of 36 BALB/C mice divided into twelve equal groups were used. Eleven groups were administered 50 μl of inocula containing 10⁷ CFU prepared from eleven isolates of Salmonella Typhimurium, administering one isolate in each group. One group was kept as negative control and each mouse in this group was given 0.5 ml of normal saline per os. The study was conducted for 15 days during which symptoms viz., ruffled feathers, hunched posture, etc., exhibited by the mice were observed and deaths were recorded. At necropsy, gross lesions of moderate to severe focal hepatic necrosis characteristic of Salmonella infection were observed. In some cases, brain and spleen were congested. No significant gross lesions were observed in heart, lung and kidney. Salmonella was isolated from liver, spleen and brain of mice that died1^st to 4^th day post- exposure. Surviving mice were sacrificed on 14^th day post- exposure, three of these had necrotic foci on the liver and Salmonella was isolated from all of these mice.