Molecular Detection of Cryptosporidium spp. in Coypu ( Myocastor coypus ) in China: Genetic Diversity and Zoonotic Potential

Introduction Cryptosporidium is a globally important enteric pathogen commonly reported in rodents. The coypu ( Myocastor coypus ) is a large rodent adapted to semi‐aquatic environments and is increasingly farmed as a fur‐bearing animal. Methods To assess the occurrence and zoonotic potential of Cryptosporidium in farmed coypus across China, a total of 308 faecal samples were collected from seven cities and screened via PCR targeting the small subunit ( SSU ) rRNA gene. Positive samples were further analysed with nested PCR targeting the 60‐kDa glycoprotein ( gp60 ) gene. Results The overall infection rate was 8.8% (27/308), with city‐level prevalence ranging from 0% (0/22) to 19.4% (19/98). Four distinct Cryptosporidium species/genotypes were identified: C. ubiquitum ( n = 15), C. myocastoris ( n = 5), C. parvum ( n = 1), and the Cryptosporidium deer mouse genotype IV ( n = 6). Further subtyping classified the C. parvum isolate as IIaA18G1R1 ( n = 1) and revealed a novel C. ubiquitum subtype family, designated XIIk ( n = 13). Phylogenetically, XIIk clustered with the zoonotic XIIa group. Conclusions These results reveal the genetic diversity of Cryptosporidium in farmed coypus and highlight the need for further investigation of its zoonotic potential.