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The present report gives a survey of the occurrence in Denmark of DVH, its symptoms,the course of the disease, transmission of infection and the posibilities of prevention and control. As it appears from Figs. 2 and 3, DVH can cause considerable losses for the individual producers, for whom it is difficult to safeguard themselves against new infections because of the resistance and stability of the DVH virus in infected premises. Three possibilities of controlling DVH are pointed out: isolation of the flocks, serum therapy and vaccination.

Duck virus enteritis occurred in the spring of 1982 among domesticated mallards, Pekin ducks and geese producing eggs for the same hatchery. Wild mallards may have introduced the infection to the domestic birds. High mortality occurred in one flock of Pekin ducks and in young geese. Mallards were also affected, but less severely. Gross and microscopic lesions were in general typical for DVE. Virus was demonstrated by electron microscopy of Bursa fabricii from experimentally infected ducklings. Neutralizing antibodies were found in serum from ducks, surviving an acute outbreak in the flock. Vaccination was performed and hygienic precautions taken, and transmission from infected flocks to progeny was negligible.

One-day-old chickens were fed ochratoxin A-contaminated diets at 2 levels: 0.3 and 1 mg ochratoxin A per kg feed, for 341 days. The only observable lesion to develop was a kidney damage comparable with the naturally occurring avian nephropathy. The changes in renal function were characterized by impairment of glomerular and tubular function, indicated by a decreased inulin clearance, TmPAH and decreased urine concentrating capacity. The changes of renal structure included degeneration of the tubular epithelium accompanied by regeneration. At slaughter, the kidneys, liver and muscular tissue of the birds contained residues of ochratoxin A (up to 50 mug per kg). As all the birds would have passed the meat inspection because no macroscopical lesions were present, this represents a possible health problem.