ABSTRACT Cryptosporidium species are the causative agent of cryptosporidiosis and common intracellular parasites that can infect a wide range of vertebrates, including snakes. In previous studies, Cryptosporidium species infections have been reported in snakes in Asia, Europe, and North America. However, limited information is available about the prevalence and molecular characterization of Cryptosporidium in captive snakes in China. Fecal specimens from 609 captive snakes were collected from Beijing (n = 227), Chengdu (n = 12), Dazhou (n = 359), and Ziyang (n = 11). The partial small-subunit ( SSU ) rRNA gene was amplified by nested polymerase chain reaction to determine the prevalence of Cryptosporidium , and a phylogenetic tree was constructed to assess evolutionary relationships and genetic characteristics. The overall prevalence of Cryptosporidium was 1.97% (12/609). BLAST and phylogenetic analysis of the small subunit ribosomal RNA ( SSU rRNA ) gene showed that the parasites belonged to Cryptosporidium serpentis . To the best of our knowledge, this is the first study to report the prevalence of Cryptosporidium in snakes of southwestern and northern China and provides preliminary data for the control and prevention of cryptosporidiosis in the investigated areas.

Given the paucity of literature available on rabbits infected with Cryptosporidium in Sichuan Province (China), 290 fecal samples were collected from rabbits in the animal house of Sichuan Agricultural University, China and examined for Cryptosporidium oocysts using the Sheather's sucrose flotation technique and a modified acid-fast staining method. Three samples tested positive (prevalence = 1.03%). The positive isolates were genotyped by sequence analysis of the 18S rRNA, HSP70, COWP, and Cp135 genes and characterized by PCR-restriction fragment length polymorphism (RFLP) analysis of the 18S rRNA gene. Phylogenetic analysis was established using the neighbor-joining (NJ) method. All the isolates were identified as Cryptosporidium cuniculus . Further subtyping of the positive isolates was performed by DNA sequencing of the 60-kDa glycoprotein (gp60) gene. Only 1 subtype family was detected, Va, which was proposed to be a new subtype, VaA31. This study is the first report about the prevalence, genetic identification, and Cp135 gene of C. cuniculus in rabbits in Sichuan Province, China. The obtained results indicate that the C. cuniculus subtype in rabbits in Sichuan Province is unique.