Experimentally induced porcine proliferative enteritis in specific-pathogen-free pigs

Area of Science:

• Veterinary Pathology
• Microbiology
• Swine Diseases

Background:

• Proliferative enteritis is a significant enteric disease in pigs.
• The causative agent of proliferative enteritis has been identified as Lawsonia intracellularis, but other bacteria may play a role.

Purpose of the Study:

• To investigate the role of Campylobacter sputorum subsp mucosalis in the pathogenesis of proliferative enteritis in pigs.
• To compare the effects of crude inoculum from naturally infected pigs with pure cultures of Campylobacter sputorum subsp mucosalis.

Main Methods:

• Thirty-three specific-pathogen-free pigs were inoculated intragastrically with either crude inoculum, Campylobacter sputorum subsp mucosalis cultures, or a control.
• Pigs were euthanized at various time points post-inoculation for histological examination.
• Light and electron microscopy were used to identify bacteria and characterize lesions.

Main Results:

• Intestinal lesions, including leukocytic exudate and inflammation, were observed in pigs inoculated with crude inoculum and Campylobacter sputorum subsp mucosalis.
• Lesions were most prominent over ileal Peyer's patches and involved crypt epithelial cell proliferation and macrophage infiltration.
• Campylobacter sp-like organisms were found within affected epithelial cells, and lesions progressed to crypt elongation and villi loss.

Conclusions:

• Campylobacter sputorum subsp mucosalis can induce lesions consistent with proliferative enteritis in pigs.
• The experimental model successfully replicated key pathological features of the disease, including bacterial colonization and inflammatory responses.