Pathologic analysis of mink mortality in New England mink.

The underlying cause of death of a group of New England mink, which died in 1969 to 1970 was explored. PCB and chlorinated hydrocarbon pesticide levels were measured. Aroclor 1254 levels in these mink were elevated 73 fold over levels in healthy mink in 1974. DDT levels were elevated 5 times and DDE 3 times over those control animals. Gross pathology revealed desions of the lungs, liver and kidneys. There lesions were confirmed microscopically. The lungs of the New England mink showed inflammation and congestion. Areas of inflammation were also present in the liver. Massive areas of necrosis were seen in the kidneys, both in the medullary and cortical areas. Kidney involvement was greater than any other organ. P.A.S. positive material was seen in each of these organs with the kidneys showing largest amounts of this material. Since the New England mink did not show lesions of the G.I. tract, did not exhibit fatty degeneration of the liver, which PCB toxicity is known to induce in mink and because they showed areas of congestion, inflammation and positive P.A.S. material, PCB's were not considered the toxic agent. However, fungus or bacterial infection might be the causative agent.