Haematological changes in layers experimentally infected with salmonella gallinarum

Abstract

Aim: The present study was conducted to investigate the haematological changes in layers experimentally infected with Salmonella gallinarum. Methods: A total of 20 eighteen-week-old ISA Brown layers were used for the experiment. The birds were randomly divided into two groups, infected and control, of 10 birds each. To establish the infection, each bird in the infected group was orally administered 0.5 ml of the inoculum containing 9x10 8 CFU/ml. Similarly, birds in the control group were each administered 0.5 ml normal saline only. Following the inoculation, all experimental birds were closely monitored for clinical signs of fowl typhoid. Blood samples were collected from each group at day zero (Day 0), 2, 4, 7, 14, 21, 28, 35 and 42, post-infection (pi) and used for determination of haematological parameters. By day seven post infection, all birds in the infected group showed clinical signs typical of fowl typhoid; namely weakness, ruffled feathers, huddling together, somnolence, greenish-yellow diarrhea, weight loss, drop in egg production, decrease in feed and water consumption and mortality rate (50%). There were, however, macrocytic hypochromic anaemia, leuckocytosis and heterophilia. In conclusion, the experimental Salmonella Gallinarum infection induced acute anaemia, leukocytosis, heterophilia and lymphopenia.