Naslov
Multilocus genotyping of Giardia duodenalis from livestock

Autori
Beck, Relja ; Grana, L. ; Lalle, Marco ; Habluetze A. ; Tonanzi, Daniele ; Marinculić, Albert ; Edoardo, Pozio ; Cacci&ograve ; , Simone Mario

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
The Second International Giardia and Cryptosporidium Conference

Mjesto i datum
Morelia, Meksiko, 13.05.2007. - 18.05.2007

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Giardia duodenalis; multilocus genotyping; livestock; zoonotic

Sažetak
Multilocus genotyping of Giardia duodenalis from livestock Giardia duodenalis is a widespread parasite of mammalian species, including humans. Due to its invariant morphology, investigation on aspects such as host specificity and transmission patterns requires direct genetic characterization of cysts from host samples. Livestock are known to be infected with genetically different G. duodenalis assemblages, including zoonotic (A and B) and host-adapted (E) assemblages. The prevalence of these assemblages varied considerably in the different surveys performed to date, albeit data are still too scarce to draw firm conclusions. Importantly, inferences about the zoonotic potential of G. duodenalis cysts from livestock (mainly calvs) have been based on the analysis of single markers, especially the small subunit ribosomal DNA (rDNA), and this approach has now been questioned. In this work, samples from calves, lambs, sheep, pigs and water buffaloes collected in Italy and in Croatia (n=50), were analysed by PCR and direct sequencing of fragments of the rDNA, b-giardin (BG), glutamate dehydrogenase (GDH), and triose phosphate isomerase (TPI) genes. Multi-locus genotypes (MLGs) of assemblage E isolates were easily defined, as typing of any isolate as E at a given marker was always confirmed by the analysis of all other markers (i.e., no evidence for assemblage “ swapping” ). However, sequence heterogeneity (i.e., the presence of 2 nucleotides at the same position after direct sequencing of PCR amplicons) was evident in some isolates, and this makes the exact identification of assemblage E MLGs difficult in these cases. Genotyping of assemblage A isolates showed a preponderance of the A1 subtype (at all markers), and since this MLG was very rarely found in human isolates from the same regions (Italy), livestock appears to play a minor role as reservoir of cysts infectious to humans.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Veterinarska medicina

POVEZANOST RADA