Limited Probiotic Effect of L1, L21 and CLFP3 to Protect Rainbow Trout against Saprolegniosis.

Previous studies have demonstrated that the strains L1, L21 and CLFP3 are probiotics against vibriosis or lactococosis in sea bass or rainbow trout. In this study, the utility of these bacterial strains in the control of saprolegniosis was evaluated. For this purpose, both in vitro inhibition studies and competition for binding sites against and in vivo tests with experimentally infected rainbow trout were carried out.

Possible Mechanisms of Action of Two Isolates as Probiotics on Saprolegniosis Control in Rainbow Trout ( Walbaum).

Probiotics have been proposed as one of the alternatives to the chemical treatments currently used in aquaculture. Recently, the possible usefulness of certain microorganisms, mainly bacteria, has been highlighted as a potential biocontrol for saprolegniosis. In the present work we investigated the possible mechanisms of action of two isolates of (LE89 and LE141) with proven ability to reduce infection in rainbow trout under experimental conditions when they are added to the tank water.

Distribution patterns of saprolegniosis cutaneous lesions in wild and farmed brown trout (Salmo trutta L.) obtained using a geographic information system (GIS).

A retrospective study was conducted using 250 clinical records of brown trout (Salmo trutta L.) with saprolegniosis by Saprolegnia parasitica, which had been collected from 8 rivers and 1 fish farm in the province of León (Spain). A geographic information system (GIS) was used to obtain skin lesion distribution patterns in males and females.

Biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum) using two bacterial isolates (LE89 and LE141) of Pseudomonas fluorescens.

The probiotic activity of 15 bacterial isolates that inhibit Saprolegnia parasitica in vitro was tested for the biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum), adding the bacteria to tank water for 14 days at a concentration of 10 bacteria ml water. Pseudomonas fluorescens LE89 and Pseudomonas fluorescens LE141 were effective in controlling experimental infection with S. parasitica since of the fish treated with LE89, 24.

Re-evaluation of the enigmatic species complex Saprolegnia diclina-Saprolegnia parasitica based on morphological, physiological and molecular data.

The phylogenetic relationships among isolates of the Saprolegnia diclina-Saprolegnia parasitica complex were investigated based on ITS rDNA sequences, and correlated with morphological and physiological characters. The isolates studied belong to five phylogenetically separate clades. The majority of presumed parasitic isolates, mostly isolated from fish lesions, fell within a clade that comprises isolates which has been variously named as S.