Prevalence and molecular characterization of <i>Cryptosporidium</i> spp. in cattle in central and Western Inner Mongolia, China.

<i>Cryptosporidium</i> spp. are apicomplexan parasites that can cause diarrhea in humans and animals, posing a health risk to both animals and humans. Molecular epidemiological analysis provides essential data for understanding <i>Cryptosporidium</i> transmission, treatment, and control. In this study, SSU rRNA was used to determine the prevalence of <i>Cryptosporidium</i> in cattle. A total of 847 fecal samples were collected from 16 farms in central and western Inner Mongolia (Hohhot, Ordos, Bayan Nur and Baotou), and 15.94% (135/847) of samples were positive. Overall, <i>Cryptosporidium</i> was detected in all seasons. Calves up to 2 months of age were found with the highest rate of infection (33.33%). In older animals, there was a significant decline in infection rates with increasing age. The species, <i>C. parvum</i> (<i>n</i> = 105), <i>C. andersoni</i> (<i>n</i> = 21) and <i>C. bovis</i> (<i>n</i> = 9) were detected, individually, or in mixed infections involving two or three <i>Cryptosporidium</i> spp., and five subtypes of <i>C. parvum</i> (IIdA17G1, IIdA17G2, IIdA18G1, IIdA19G1, IIdA20G1) were identified. Our findings provide data to support the epidemiological control of <i>Cryptosporidium</i> infection in cattle.