Prevalence of Toxoplasma gondii and Cryptosporidium in Feral and Farmed American Mink ( Neovison vison ) in Denmark

Purpose To investigate the prevalence of Cryptosporidium spp. infection and Toxoplasma gondii antibodies in farmed and feral mink in Denmark. Methods We examined meat juice from 235 feral mink and 306 farmed mink for T. gondii antibodies, and faecal samples from 113 feral mink and 166 farmed mink for Cryptosporidium oocyst excretion. Meat juice was analysed using a commercial indirect enzyme-linked immunosorbent assay and oocyst excretion was identified by a modified Ziehl–Neelsen method. Results All farmed mink tested sero-negative, while 53.6% of feral mink were T. gondii sero-positive. The probability of being sero-positive for T. gondii was not associated with recent escapes from farms ( p = 0.468), but was significantly higher for male feral mink (64.2%) than female feral mink (42.5%) ( p = 0.0008). Only one feral mink and four farmed mink (2.4%) excreted Cryptosporidium oocysts. Conclusion Farmed mink were all T. gondii sero-negative, whereas approximately half the feral mink were sero-positive. Cryptosporidium prevalence in farmed and feral mink were low. Overall, the public health risk of transmission of these two parasites via mink in Denmark is low.