Cryptosporidium avium n. sp. (Apicomplexa: Cryptosporidiidae) in birds

Abstract

The morphological, biological, and molecular characteristics of Cryptosporidium avian genotype V are described, and the species name Cryptosporidium avium is proposed to reflect its specificity for birds under natural and experimental conditions. Oocysts of C. avium measured 5.30–6.90 μm (mean = 6.26 μm) × 4.30–5.50 μm (mean = 4.86 μm) with a length to width ratio of 1.29 (1.14–1.47). Oocysts of C. avium obtained from four naturally infected red-crowned parakeets (Cyanoramphus novaezealandiae) were infectious for 6-month-old budgerigars (Melopsittacus undulatus) and hens (Gallus gallus f. domestica). The prepatent periods in both susceptible bird species was 11 days post infection (DPI). The infection intensity of C. avium in budgerigars and hens was low, with a maximum intensity of 5,000 oocysts per gram of faeces. Oocysts of C. avium were microscopically detected at only 12–16 DPI in hens and 12 DPI in budgerigars, while PCR analyses revealed the presence of specific DNA in faecal samples from 11 to 30 DPI (the conclusion of the experiment). Cryptosporidium avium was not infectious for 8-week-old SCID and BALB/c mice (Mus musculus). Naturally or experimentally infected birds showed no clinical signs of cryptosporidiosis and no pathology was detected. Developmental stages of C. avium were detected in the ileum and caecum using scanning electron microscopy. Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. avium is genetically distinct from previously described Cryptosporidium species.

Review of Cryptosporidium and Giardia in the eastern part of Europe, 2016

“…The studies also resulted in the description of C. avium , C. proliferans , C. scrofarum , C. fragile , C. erinacei and C. testudinis as novel species of the genus Cryptosporidium [30-46]. In the Czech Republic, Cryptosporidium spp.…”

Detection and characterization of Cryptosporidium species and genotypes in three chicken production systems in Brazil using different molecular diagnosis protocols

“…Cryptosporidiosis is one of the most prevalent protozoan infections in birds, and it manifests as a respiratory or digestive disease (Ryan, 2010;Nakamura and Meireles, 2015). Among the 31 species of Cryptosporidium that infect several vertebrates, only four infect birds: C. meleagridis, C. baileyi, C. galli and C. avium (previously known as avian genotype V) (Holubová et al, 2016;Ryan et al, 2016).…”

Subtyping ofCryptosporidium cuniculusand genotyping ofEnterocytozoon bieneusiin rabbits in two farms in Heilongjiang Province, China

“…To date, 30 Cryptosporidium species and more than 40 genotypes have been described, and among them, 20 Cryptosporidium species/genotypes have been reported in humans, with C. hominis and C. parvum responsible for the majority of infections [15, 23, 28, 41, 42]. For E. bieneusi , more than 240 ITS genotypes have been identified worldwide [18, 45], and at least 70 genotypes have been found in humans, with 33 genotypes being zoonotic [21, 33, 61].…”