title: Prevalence and genetic characterizations of Cryptosporidium spp. in pre-weaned and post-weaned piglets in Heilongjiang Province, China.
abstract: BACKGROUND
  Cryptosporidium spp. are common intestinal protozoa of humans and animals. There have been few studies conducted on the molecular characterizations of pig-derived Cryptosporidium isolates worldwide, especially in China. Thus, the aim of the present study was to understand the prevalence, distribution and genotypes of Cryptosporidium in pigs in Heilongjiang Province, China.
  
  
  RESULTS
  A total of 568 fecal samples from pre-weaned and post-weaned piglets were collected from eight pig farms from four areas of Heilongjiang Province. The average infection rate of Cryptosporidium was 1.6% (9/568) by microscopy. 113 samples were subjected to PCR amplification of the small subunit (SSU) rRNA gene of Cryptosporidium, with 55.8% (63/113) being positive for Cryptosporidium. Cryptosporidium suis (n = 31) and C. scrofarumn (n = 32) were identified by DNA sequencing of the SSU rRNA gene. Three types of C. scrofarumn were found at the SSU rRNA locus, with one novel type being detected. Using species/genotype-specific primers for pig-adapted Cryptosporidium spp., 22 and 23 respectively belonged to C. suis and C. scrofarum mono-infections, with 18 co-infections detected. The infection peaks for C. suis (60%, 24/40) and C. scrofarum (51.2%, 21/41) were respectively found in the piglets of 5 to 8 weeks and more than 8 weeks.
  
  
  CONCLUSIONS
  The detection of C. suis and C. scrofarum in pre-weaned and post-weaned piglets has public health implications, due to the fact that the two species are both zoonotic Cryptosporidium. The novel C. scrofarum type detected may be endemic to China.
authors.affiliation: Department of Parasitology, Harbin Medical University, Harbin, Heilongjiang, China.
authors.forename: Weizhe
authors.initials: W
authors.lastname: Zhang
authors.forename: Fengkun
authors.initials: F
authors.lastname: Yang
authors.forename: Aiqin
authors.initials: A
authors.lastname: Liu
authors.forename: Rongjun
authors.initials: R
authors.lastname: Wang
authors.forename: Longxian
authors.initials: L
authors.lastname: Zhang
authors.forename: Yujuan
authors.initials: Y
authors.lastname: Shen
authors.forename: Jianping
authors.initials: J
authors.lastname: Cao
authors.forename: Hong
authors.initials: H
authors.lastname: Ling
mesh_terms: D000818:Animals; D002681:China / Q000453:epidemiology; D003457:Cryptosporidiosis / Q000662:veterinary*; D003458:Cryptosporidium / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D005243:Feces / Q000469:parasitology; D005838:Genotype; D008969:Molecular Sequence Data; D015995:Prevalence; D012335:RNA, Ribosomal / Q000235:genetics; D013552:Swine / Q000469:parasitology*; D013553:Swine Diseases / Q000453:epidemiology*; D014886:Weaning
chemical_list: D012335:RNA, Ribosomal