SUMMARYA non-pathogenic, piliated strain of Escherichia coli (BT-7;Frommer et al., 1990), isolated from a meat-type chicken flock, was studied as a candidate for a live vaccine to protect chickens from E. coli infection. Active immunization provided substantial protection of chicks vaccinated at 14 or 21 days of age, resulting in better resistance to challenge than in those vaccinated at 1 or 7 days. Chicks vaccinated at 21 days of age and challenged 1 week later with pathogenic E. coli strains 01-.K1, 02:K1 or 078:K80, exhibited good protection for at least 2 weeks against all strains. Three vaccination routes were found to give the highest resistance to challenge with pathogenic E. coli strain 078:K80. Intramuscular (i.m.) at 7 and 21 days of age, i.m. at 21 days of age and spray at 7, followed by per os at 21 days of age. Vaccination per os once at 7 or twice at 7 and 21 days resulted in good protection. Chicks exhibiting high antibody titres by ELISA were well-protected against challenge.

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The feeding of a shipment of imported corn was associated with a severe reduction in growth and increased mortality in geese, and increased mortality in broilers. Pathological examinations revealed hepatopathy, visceral gout and mild nephropathy in geese, and in broilers an hepatopathy, which was often severe, and ascites. Samples of feed from affected geese farms were examined for up to 24 mycotoxins, and ochratoxin was found in 6 of 15 samples at levels up to 930 ng/g. The syndrome was experimentally reproduced by feeding geese and broilers suspect feeds with the natural ochratoxin contamination. It is believed that another, unidentified, mycotoxin was the major cause of the hepatotoxicity, and that ochratoxin served in this case as an indicator of a multi-mycotoxin involvement.