DETERMINATION OF LETHAL EFFECT OF SALMONELLA TOXIN ISOLATED FROM LAYER BIRDS

Abstract

The study was conducted for determination of lethal effects of Salmonella toxin isolated from layer birds. The chicken were collected from Paragon Poultry Farm, Rangpur and Ahana Poultry Farm, Dinajpur and brought to the Microbiology laboratory of Hajee Mohammad Danesh Science and Technology University, Dinajpur, for determination of lethal effects of Salmonella toxin and isolation and identification of Salmonella spp. from postmortem samples. The lethal effect of toxin extracted from salmonella spp. is detected in day old chicks. Percentage of toxicity in case of day old chick those were given toxin orally was 50% and in case of chicks those were inoculated intraperitonially was 80%. Out of 20 chicks 13 died, average percentage of toxicity was 65%. For Salmonella toxin extraction Salmonellae organisms were isolated and identified from layer chicken. Out of 196 organ samples 51 were found to be positive to Salmonella spp. Among the positive samples, 34 were from Paragon Poultry Farm at Rangpur and 18 were from Ahana Poultry Farm at Dinajpur. Two farms were visited with a total of 7 flocks with an average of 200 chickens per flock. Total 60 chickens were _ screened, composed of 27 pullets, 33 layers .The percentages of positive samples (liver, spleen, lung, heart,) from those farm were 29.82% and 20.70% respectively and the average prevalence of Sa/monella in the study area was 26.02%. Incase of Paragon poultry farm prevalence of salmonellosis in pullet was 23.08% and in layer bird 35.48% and in case of Ahana Poultry Farm, prevalence in pullet and layer birds were 16.67%and 23.91% respectively. In case of organs specificity, Salmonella organisms were detected from 31 samples of liver, 13 samples of spleen, 4 of lung samples and 3 of heart sample the prevalence were 38.75%, 23.21%, 10.53% & 13.64% respectively.