|Fiuza, Vagner - Universidade Estadual Do Norte Fluminense|
|Lopes, Carlos - Universidade Estadual Do Norte Fluminense|
|Oliviera, Francisco - Universidade Estadual Do Norte Fluminense|
Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/12/2015
Publication Date: 1/30/2016
Citation: Fiuza, V., Lopes, C., Oliviera, F., Fayer, R., Santin, M. 2016. New findings of Enterocytozoon bieneusi in beef and dairy cattle in Brazil. Veterinary Parasitology. 216:46-51.
Interpretive Summary: Microsporidia comprises a diverse group of obligate intracellular parasites widely recognized as important human and animal pathogens. Among Microsporidia, Enterocytozoon bieneusi is the most commonly reported species in humans, mainly associated with diarrhea. It also has been reported worldwide in water, and in wild, domesticated, and food-producing farm animals, raising concerns for water-borne, food-borne, and zoonotic transmission. Although Brazil has the world’s second largest population of cattle and is the largest exporter of beef, there are no data on E. bieneusi in Brazilian cattle. To fill this knowledge gap, a study was undertaken between Brazilian and ARS scientists to determine the prevalence of this parasite in Brazilian cattle. Fecal samples were collected from 452 cattle in the State of Rio de Janeiro. The presence of E. bieneusi was determined by polymerase chain reaction (PCR) and all PCR-positive specimens were sequenced to determine the genotype. Host factors including age, gender, dairy/beef, body composition, and fecal consistency were included in the study. We detected the microsporidian parasite in 17.5% of Brazilian cattle, with a higher prevalence in younger animals than in heifers and adults. More dairy cattle (26.2%) were infected than were beef cattle (9.7%). No correlation was found between infection and gender, body composition score, and fecal consistency. Molecular characterization revealed 12 genotypes; five previously reported in cattle (BEB4, BEB8, D, EbpA and I), and seven novel genotypes (BEB11 to BEB17). The identification of genotypes in Brazilian cattle that have previously been reported in humans highlights the potential risk of zoonotic transmission and suggests that the role of cattle in transmission of human infections requires further study. This information will be of interest to other scientists and regulatory agencies.
Technical Abstract: Microsporidia are widely recognized as important human pathogens with Enterocytozoon bieneusi as the most common species infecting humans and animals, including cattle. Although Brazil has the second largest cattle herd in the world and it is the largest exporter of beef there are no data on the presence or impact of E. bieneusi on this important population. To fill this knowledge gap, fecal specimens were collected from 452 cattle from pre-weaned calves to adult cattle in the state of Rio de Janeiro. Host factors including age, gender, dairy/beef, body composition, and fecal consistency were included in the study. Using molecular methods, E. bieneusi was found in 79/452 (17.5%) fecal specimens. This represents the first report of this parasite in Brazilian cattle. A significantly higher prevalence was found in calves less than 2 months of age (27.6%) and those 3-8 months of age (28.8%) versus heifers (14.1%) and adults (1.4%). Dairy cattle (26.2%) had a higher prevalence than beef cattle (9.7%). No correlation was found between infection and gender, body composition, and fecal consistency. Molecular characterization of the internal transcribed spacer (ITS) revealed 12 genotypes; five previously reported in cattle (BEB4, BEB8, D, EbpA and I), and seven novel genotypes (BEB11 to BEB17). The finding of zoonotic genotypes in cattle in Brazil highlights the risk of human contamination with E. bieneusi spores through direct contact, especially with young dairy cattle, and environmental contamination affecting water and plants.