Molecular survey of Cryptosporidium spp. in calves from the state of Mato Grosso, Brazil

Cryptosporidium spp. is a protozoan that infects a wide range of vertebrate hosts; it has been reported to be the cause of severe illness or death in livestock worldwide, which leads to decreased performance and production losses, especially in young animals. This study investigated the presence of Cryptosporidium in calves from beef farms in the state of Mato Grosso, midwestern Brazil. For this purpose, fecal samples from 237 animals aged <= 45 days, raised in 20 rural properties were subjected to DNA extraction and nested polymerase chain reaction (nPCR) targeting 18S ribosomal RNA (18S rRNA) gene followed by sequencing. Additionally, positive samples, previously identified as Cryptosporidium parvum by sequencing and phylogenetic analyses based on 18S rRNA gene, were subsequently analyzed focusing the amplification and sequencing using nPCR of a fragment of the 60 kDa glycoprotein (gp60) gene. Of the 237 fecal samples analyzed by PCR (18S rRNA), 50 (21.1%) fecal samples were positive for Cryptosporidium spp., while 14 (70%) of the 20 properties had at least one positive animal. The following Cryptosporidium species were detected: C. bovis, C. parvum, and C. ryanae. Thereafter, two potentially zoonotic subtypes (IIaA15G2R1 and IIaA16G3R1) of C. parvum were identified based on gp60 gene sequences. This study resulted in the detection of subtype IIaA16G3R1 for the first time in South America and showed a wide distribution of the protozoan in beef farms in the studied area of the State.