Report and genetic identification of Amyloodinium ocellatum in a sea bass (Dicentrarchus labrax) broodstock in Portugal

In this paper we report a case of amyloodiniosis in a sea bass (Dicentrarchus labrax) broodstock in Portugal. Microscopic examination of gill filaments showed the presence of trophonts while histological observation revealed gills epithelial hyperplasia, hypertrophy and lamellar fusion of secondary lamellae. The amplification and sequencing of the small subunit ribosomal RNA gene allowed the identification of the parasite as Amyloodinium ocellatum. It was also possible to amplify a partial sequence of ribosomal RNA from a Colpodellid, a predator of protists.This work was supported by DIVERSIAQUA and SAUDE&AQUA projects [MAR2020 16-02-01-FMP-0066 and Mar2020 02.05.01-FEAMP-0009, respectively]. Márcio Moreira has a PhD grant from FCT - Foundation for Science and Technology (SFRH/BD/118601/2016). This study also received Portuguese national funds from FCT - Foundation for Science and Technology through project UID/Multi/04326/2019.