The aim of this study was to determine the prevalence of Cryptosporidium species and genotypes in birds kept in captivity in Brazil. A total of 966 samples from 18 families of birds was collected and stored in 5% potassium dichromate solution at 4 degrees C until processing. Oocysts were purified in Sheather sugar solution following extraction of genomic DNA. Molecular analyses were performed using nested-PCR for amplification of fragments of the 18S subunit of rRNA gene and of the actin gene. Amplification of Cryptosporidium DNA fragments was obtained in 47 (4.86%) samples. Sequencing of amplified fragments and phylogenetic analyses allowed the identification of Cryptosporidium baileyi in a black vulture (Coragyps atratus), a domestic chicken (Gallus gallus domesticus) and a saffron finch (Sicalis flaveola); Cryptosporidium galli in canaries (Serinus canaria), a cockatiel (Nymphicus hollandicus) and lesser seed-finches (Oryzoborus angolensis); Cryptosporidium meleagridis in a domestic chicken (G. g. domesticus); Cryptosporidium parvum in a cockatiel (N. hollandicus); Cryptosporidium avian genotype I in a canary (S. canaria) and an Indian peafowl (Pavo cristatus); Cryptosporidium avian genotype II in ostriches (Struthio camelus) and Cryptosporidium avian genotype III in a cockatiel (N. hollandicus) and a peach-faced lovebird (Agapornis roseicolis).

Cryptosporidiosis is one of the main protozoan infections in birds. It manifests as either a respiratory or a digestive illness, and it affects a very large number of avian species across several continents. The aim of this review is to report on the main results of studies on cryptosporidiosis among birds and the importance of these results to veterinary medicine and public health.Keywords: Cryptosporidium spp., wild birds, poultry. ResumoA criptosporidiose constitui-se em uma das principais infecções por protozoários em aves, manifestando-se como enfermidade respiratória ou digestiva, em dezenas de espécies aviárias, em vários continentes. O objetivo desse trabalho foi relatar, por meio de revisão de literatura, os principais resultados de estudos sobre criptosporidiose em aves e sua importância para a medicina veterinária e saúde pública.Palavras-chave: Cryptosporidium spp., aves selvagens, aves domésticas.

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Due to the scarcity of information related to the epidemiology of Cryptosporidium infection in passerine birds, this study aimed to determine the periodicity of fecal shedding of Cryptosporidium spp. oocysts, after natural infection, and its clinical signs, mortality, and molecular characterization. Four hundred eighty fecal samples were collected from 40 birds, including 372 samples from 31 adult birds and 108 samples from nine young birds (up to 12 months old), housed in five aviaries, monthly from September 2007 to September 2008, with the exception of April. The birds originated from aviaries in which the following species were raised: great-billed seed-finch (Oryzoborus maximiliani), lesser seed-finch (Oryzoborus angolensis), ultramarine grosbeak (Cyanocompsa brissonii), and rusty-collared seedeater (Sporophila collaris). The samples were preserved in 2.5% potassium dichromate at 4 degrees C until processing. The oocysts were purified by centrifugal flotation in Sheather's solution, followed by genomic DNA extraction and molecular characterization of oocysts using the nested polymerase chain reaction for amplification of fragments of the 18S subunit of rRNA gene. Intermittent shedding of oocysts was observed by positive amplification for Cryptosporidium spp. in 91 (24.5%) samples of adult birds and 14 (13%) of young birds. The sequencing of the amplified fragments enabled the identification of Cryptosporidium galli. Although all the aviaries had birds positive for C. galli, morbidity or mortality was observed in only one aviary and was associated with concomitant infection with Escherichia coli and Isospora sp.

Proventricular infection by Cryptosporidium sp. or Cryptosporidium galli has been associated with mortality, weight loss, diarrhea, and pasty feces. The purpose of this study is to report the occurrence of natural C galli infection in canaries (Serinus canaria), in a cockatiel (Nymphicus hollandicus), and in lesser seed-finches (Oryzoborus angolensis) with clinical complaints of apathy and sporadic mortality. Screening for Cryptosporidium spp. using microscopic examination of fecal samples and stained smears, histopathology, and nested polymerase chain reaction for actin gene and 18S ribosomal RNA gene following sequencing of amplified fragments allowed for the identification of C galli. To the best of our knowledge, this is the first report of C galli in birds in Brazil and the first report of this species in lesser seed-finches.