An Outbreak of Excessive Neonatal Mortality in Four Danish Mink Farms

An outbreak of increased mortality among mink kits in 4 Danish mink farms in 1982 is described. A comparison with data from 4 non-affected farms revealed obvious differences in neonatal mortality in the period from parturition until May 15th (early neonatal mortality) and in the period from May 15th to June 30th (late neonatal mortality) between the 2 groups of farms. The populations are described in terms of age, origin, types of mink and the extent of transfer of breeding females among the farms. Postmortal examination showed consistent pathological changes, but the etiology and pathogenesis of the diseases is uncertain until now. The increased mortality of kits, however, was accompanied by increasing numbers of Aleutian Disease (AD) positive reactors in the 4 populations.