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

Abstract

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.

Prevalence of Toxoplasma gondii in Wild American Mink (Neogale vison): The First Serological Study in Germany and Poland

“…Serological studies on wild mink populations with comparable sample sizes (≥200 individuals) were conducted in Denmark and Spain. The seroprevalence of 45.36% (95% CI: 38.39–52.41%) determined in the present study was comparable to the prevalence of 53.6% (126/235; 95% CI: 40.0–60.0%) reported from Denmark [ 34 ], which was also determined using ELISA based on meat juice. A significantly higher seroprevalence was reported from Spain [ 51 ], where T. gondii antibodies were found in 78.8% (534/678; 95% CI: 75.5–81.8%) of wild minks using an indirect modified agglutination test (MAT) based on serum samples.…”

“…In the original distribution area, the seroprevalence of T. gondii in wild minks was between 40 and 100% [ 13 , 44 , 45 , 46 ]. In areas where the species has been introduced, including South America, Europe, and Asia, a seroprevalence of between 26 and 100% has been reported [ 34 , 47 , 48 , 49 , 50 , 51 ]. However, seroprevalence values were mostly based on small sample sizes and sometimes on individual animals.…”

“…Although the antibody concentration in meat juice is lower than in serum, serological analyses showed that both media correlate well [ 41 ]. Meat juice has been successfully used in the past to monitor for antibodies against T. gondii , including in mammalian predators [ 34 , 42 , 43 ]. The optical density (OD) was measured at 450 nm using a microplate reader (Tecan Infinite ® F50 Plus, Tecan Trading AG, Männedorf, Switzerland).…”

“…Serological studies on T. gondii infections in minks were mostly performed on animals from fur farms [ 28 , 29 , 30 , 31 , 32 , 33 , 34 ], while studies on wild minks are generally rare and often based on small sample sizes [ 35 , 36 , 37 ]. The aim of the present study was to analyse for the first time the seroprevalence of T. gondii in a larger sample of wild minks in order to assess the contamination of freshwater ecosystems in Germany and Poland.…”

Wild Mesocarnivores as Reservoirs of Endoparasites Causing Important Zoonoses and Emerging Bridging Infections across Europe

“…American minks were found serologically or molecularly positive for T. gondii in the UK, Poland, and Denmark, reaching a prevalence of up to 78.8% in Spain [ 17 , 303 , 306 , 367 , 368 , 369 ]. Infection with Cryptosporidium was detected in animals from Ireland, Spain, and the Czech Republic with prevalences of 6.17%, 24.20%, and 6%, respectively.…”