A survey of ochratoxin A contamination in feeds and sera from organic and standard swine farms in northwest Italy

BACKGROUND: A survey was carried out on conventional (n = 11) and organic (n = 4) swine farms in northwest Italy in order to investigate the occurrence of ochratoxin A (OTA) in feed and serum samples collected from September 2006 to March 2009. Each farm was sampled twice and a total of 30 feed samples and 285 serum samples were collected. OTA levels were determined through extraction, immunoaffinity column purification and high-performance liquid chromatography analysis coupled with fluorimetric detection. RESULTS: All feed samples resulted to be contaminated with OTA at levels ranging from 0.22 to 38.4 microg kg(-1). The OTA concentrations found in organic feed samples were significantly higher (P < 0.05) than those found in conventional feed samples. All serum samples resulted to be contaminated with OTA at levels ranging from 0.03 to 6.24 ng mL(-1). The OTA concentrations found in organic serum samples were significantly higher (P < 0.001) than those found in conventional serum samples. CONCLUSION: None of the feed samples contained more than the maximum level (50 microg OTA kg(-1), considering a feed moisture content of 120 g kg(-1)) recommended by the European Commission for OTA in complementary and complete swine feedstuffs. The OTA contamination of organic feed and serum samples was found to be significantly higher than that of conventional feed and serum samples.