1a. Objectives (from AD-416):
The objective of this cooperative research project is to develop multiplex peptide nucleotide acid (PNA) chip and immune biomarkers associated with food-borne pathogens.
1b. Approach (from AD-416):
NVRQS will develop multiplex PNA chip by identifying SNP of food-borne pathogens and validate PNA chip for diagnosis and detection of Clostridium, Salmonella and Campylobacter. ARS will develop disease challenge models to evaluate vaccines against poultry food-poisoning pathogen, develop and optimize real-time RT-PCR for detection of C. septicum and C. perfringens, develop ELISA for chicken cytokine detection to identify immune biomarkers associated with C. perfringens and C. septicum and evaluate potential vaccine candidates of Clostricium proteins.
3. Progress Report:
Necrotic enteritis, an intestinal infection, and Gangrenous dermatitis, a severe skin infection, are important bacterial diseases of poultry caused by the bacterium Clostridium perfringens. Although the same microorganism is responsible for both diseases, Necrotic enteritis and Gangrenous dermatitis differ in important aspects, such as clinical signs, disease effect on specific tissues, and age of onset. The primary virulence factors of Clostridium perfringens are five toxins the bacteria produce that cause major gut damage. While antibodies that neutralize the effect of Clostridium perfringens toxins appear to offer protection against infection in mammals, the serological responses against these toxins have not been evaluated. Therefore, we measured the serum antibody levels for two of the Clostridium perfringens toxins in commercial birds from field outbreaks of Necrotic enteritis and Gangrenous dermatitis using an antibody-based assay. The results showed that the levels of antibodies against two of the toxins were significantly higher in apparently healthy chickens compared to birds with clinical signs of Necrotic enteritis or Gangrenous dermatitis. This suggested that these anti-toxin antibodies may play a role in protection against both diseases.