Abstract.A 2-year-old domestic ferret that appeared clinically healthy was repeatedly seropositive for Aleutian mink disease parvovirus (ADV) over a 2-year observation period. Antibody titers, determined by counter-immunoelectrophoresis, ranged from 1024 to 4096. Viral DNA also was identified in serum, urine, feces, and blood cell fractions by polymerase chain reaction analysis. Ultimately, DNA in situ hybridization revealed ADV DNA in histologic sections of various tissues and organs. These data indicate that this asymptomatic ferret was persistently infected with ADV.Key words: Aleutian disease virus; counter-immunoelectrophoresis; PCR; in situ hybridization. Aleutian mink disease parvovirus (ADV) is naturally occurring parvovirus that infects mustelids such as mink and ferrets. 3,7,8 The disease was first described in Aleutian mink, which have an increased susceptibility to disease resulting from a Chediak-Higashi-like defect in lysosomal membrane function and reduced cell-mediated immune responses necessary for combating viral infections. 4 Normal or wild-type mink are asymptomatic or have mild to moderate clinical signs of disease, chronically elevated antibody titers, and no detectable viremia or transient viremia depending on the strain of ADV. 6 Experimental infections of ferrets with minkderived strains of ADV have resulted in clinical scenarios similar to that of mink with dark coat colors. 6,15 Natural ADV outbreaks in ferret shelters and multiple ferret households have been increasingly reported. 11,14 Common clinical signs associated with ADV infection in ferrets include chronic progressive weight loss, cachexia, malaise, and melena. Ataxia leading to posterior paralysis, tremors, and convulsions has also been observed. 11,14 Little is known about the pathogenesis of natural ADV infection in ferrets or the route by which viral shedding occurs.Serum from a clinically normal, 2-year-old, male, sable point ferret was sent to the University of Georgia College of Veterinary Medicine to test for ADV. After an initial positive test result, serum samples from the ferret were submitted intermittently for anti-ADV antibody testing over a period of 1.5 years. Counter-immunoelectrophoresis was performed to determine an endpoint antibody titer within the range of 1:4 through 1:16,384. Nine serum samples were consistently positive for anti-ADV antibodies with a titer Ն1024 over a period of 1.5 years (Fig. 1). Serum was also tested for the presence of ADV DNA by using a polymerase chain reaction (PCR)-based assay. 12 Eight of nine serum samples assayed yielded the appropriately sized band (Fig. 2).Additional testing of anticoagulated whole blood was done to determine which fractions were associated with viral DNA. A 1:1 mixture of PBS-diluted, heparinized blood was separated into 3 layers by using gradient centrifugation. a A commercial kit b was used to extract and purify DNA from the erythrocytes, buffy coat, and plasma fractions. These DNA samples were evaluated by PCR analysis to detect ADV. The acellular pla...