Post mortem laboratory detection of Helicobacter spp. in swine

Gastric ulcers in pigs are a major health issue, reducing productivity and welfare. Colonization of the gastric mucosa by Helicobacter spp., particularly Helicobacter suis, is considered a potential etiological factor. This study evaluated the prevalence of gastric lesions and compared three diagnostic methods -impression cytology, urease test, and real-time polymerase chain reaction (Real-Time PCR) for detecting Helicobacter spp. in pigs. Post mortem samples were collected from 137 slaughtered pigs, with three mucosal samples per stomach (fundus, pylorus, pars oesophagea), totaling 411. A subset of 20 samples, representing all stomach regions and diverse cytology/urease outcomes, was analyzed by Real-Time PCR targeting H. suis and H. pylori (ureA and 16 S rRNA genes). Macroscopic evaluation frequently revealed ulcerative or pre-ulcerative changes. The highest detection rates occurred in the fundic region (66% by cytology; 45% by urease test), supporting preferential colonization of glandular mucosa. Bacterial presence was also observed in the pars oesophagea, suggesting colonization varies with anatomical site and lesion severity. Real-Time PCR detected H. suis in 80% and H. pylori in 20% of samples, confirming its superior sensitivity and ability to differentiate species, which conventional tests cannot provide. Cytology enabled direct visualization of spiral-shaped bacteria, while the urease test was useful mainly at higher bacterial loads. In conclusion, combining macroscopic scoring with cytology, urease testing, and PCR allows comprehensive assessment of gastric lesions and Helicobacter infection. These results highlight the diagnostic advantages of molecular methods and the value of integrated approaches for surveillance and management of gastric disease in swine production.