Jejunal bacterial communities of broiler chickens affected with subclinical and clinical necrotic enteritis

Necrotic enteritis (NE) is a severe intestinal infection that affects both humans and poultry. It is caused by the bacterium Clostridium perfringens (CP), but the precise mechanisms underlying the disease pathogenesis remain elusive. This study aims explore the impact of the microbiome on NE pathogenesis. Based on the gross and histopathology lesions, jejunal contents were categorized as clinical and subclinical and metagenomics analysis was performed. Day-old broiler chickens were divided into two groups (n=20/group) as 1) control/no challenge/healthy birds; 2) birds challenged with Clostridium perfringens (CP). Both groups were fed with 20% protein up to day 18 followed by an 18-hour feed withdrawal before challenge. An abrupt increase in the protein content from 20 to 28% was done in both the groups however only group two broilers were fed with the 28% protein ration with added Fluid Thioglycollate media-grown CP culture in 1:1 (v/w) ratio for 3 consecutive days (20 to 22 days of age). At 23 days of age, the broilers were euthanized, and post-mortem examination conducted. Gross lesions were recorded, and sections of the jejunum were collected for histopathology. Based on gross and histopathology challenged birds were divided in to subclinical (microscopic NE lesions only, n=8) and clinical (macroscopic and microscopic NE lesions, n=8) and investigated for the composition of the jejunal microbiome.