Evaluation of Gross and Histopathological Score Lesions in ISA Brown Cocks Experimentally Infected with Salmonella gallinarum

Abstract

The present study investigated the gross and histopathological score lesions in Isa brown cocks experimentally infected with salmonella gallinarum. A total of 40 Isa brown cocks were randomly assigned into two groups of 20 each: Salmonella gallinarum infected and Salmonella gallinarum uninfected. At twenty three-week-old, each bird in the infected group of cock was inoculated orally into the crop by oral gavage, with 9.0 x 108 CFU/ml Salmonella gallinarum while cocks in the   control group were administered 1ml of distilled water each. The clinical signs observed in the infected group were moderate (24.7%) with mortality and morbidity of 37% and 50%, respectively. The clinical signs include: loss of appetite, somnolence and yellow-green diarrhoea. The body weights in the infected cocks were significantly (P <0.05) lower than those of uninfected cocks. Gross pathology was mild in the infected cocks on days 21 and 28 post infection and which include enlarged and congested liver, enlarged spleen and congested kidneys; moderate on days 14 and 15 pi, and severe from days 8 to 12 post infection. Histopathological changes were mild in the infected cocks on day 28 pi and were severe on days 8 and 14 pi, but moderate on days 15 and 21 pi, and which include; lymphoid depletion in the spleen, necrosis of the renal renal tubules, diffused necrosis of the hepatic cords, testicular necrosis, desquamation of the bronchiolar epithelium. The gross and histopathology findings observed in the Salmonella gallinarum infected Isa brown cocks in this study, suggest that the severity of Salmonella gallinarum on themultiple organs of the infected Isa brown cocks which resulted in mortality as observed in this present study.