Date of Completion


Embargo Period



Antonio E. Garmendia, Paulo H. Verardi

Field of Study



Master of Science

Open Access

Campus Access


Necrotic enteritis (NE) is an economically important disease of the poultry industry. It is caused by Clostridium perfringens (CP) and the pathogenesis of the disease is still unknown today. The role of alpha toxin (AT) in the pathogenesis of the disease has recently come into question. AT production and AT activity among 18 characterized CP strains was investigated. The overall AT results show that there must be other factors involved in the pathogenesis of necrotic enteritis. The protein profiles of two netB positive isolates with differing pathogenicity were used to determine potential virulence factors. The proteomic study revealed several potential virulence factors which were hyaluroanidases, glycosal hydrolases, clostripain, perfringolysin O, and sialidase. The study showed that sialidase was produced 455.1 fold higher by the pathogenic CP strain. Sialidase has been shown to be an important virulence factor of several human pathogens and it also been shown to have synergistic effects with CP AT. Therefore, the sialidase activity among the 18 characterized strains was further investigated. Even though the results of statistical analysis suggest that sialidase activity is important for disease producing capability, it was not a complete association as there was sialidase activity variation among individual strains within the same characterized group of strains. In conclusion, all of the results suggest that there is more than one factor involved in the pathogenesis of NE and identifies new research avenues to be explored.

Major Advisor

Joan Smyth