%0 Journal Article
%@ 0020-7519
%A Young, ND
%A Crosbie, PBB
%A Adams, MB
%A Nowak, BF
%A Morrison, RN
%D 2007
%F epprod:4261
%I Elsevier Ltd
%J International Journal for Parasitology
%K 18S; 28S; Amoebic gill disease; In situ hybridisation; Neoparamoeba branchiphila; Neoparamoeba pemaquidensis; Neoparamoeba perurans; rRNA; Salmo salar
%N 13
%P 1469-1481
%T Neoparamoeba perurans n. sp., an agent of amoebic gill disease of Atlantic Salmon (Salmo salar)
%U http://eprints.utas.edu.au/4261/
%V 37
%X Amoebic gill disease (AGD) is a potentially fatal disease of some marine fish. Two amphizoic amoebae Neoparamoeba pemaquidensis and Neoparamoeba branchiphila have been cultured from AGD-affected fish, yet it is not known if one or both are aetiological agents. Here, we PCR amplified the 18S rRNA gene of non-cultured, gill-derived (NCGD) amoebae from AGD-affected Atlantic salmon (Salmo salar) using N. pemaquidensis and N. branchiphila-specific oligonucleotides. Variability in PCR amplification led to comparisons of 18S rRNA and 28S rRNA gene sequences from NCGD and clonal cultured, gill-derived (CCGD) N. pemaquidensis and N. branchiphila. Phylogenetic analyses inferred from either 18S or 28S rRNA gene sequences unambiguously segregated a lineage consisting of NCGD amoebae from other members of the genus Neoparamoeba. Species-specific oligonucleotide probes that hybridise 18S rRNA were designed, validated and used to probe gill tissue from AGD-affected Atlantic salmon. The NCGD amoebae-specific probe bound AGD-associated amoebae while neither N. pemaquidensis nor N. branchiphila were associated with AGD-lesions. Together, these data indicate that NCGD amoebae are a new species, designated Neoparamoeba perurans n.sp. and this is the predominant aetiological agent of AGD of Atlantic salmon cultured in Tasmania, Australia.
%Z The definitive version is available at http://www.sciencedirect.com