Use of in vivo-induced antigen technology to identify bacterial genes expressed during solea senegalensis infection with Photobacterium damselae subsp. piscicida

The marine fish pathogen Photobacterium damselae subsp. piscicida (Phdp) is responsible for important outbreaks affecting several fish species including flatfish Solea senegalensis. The aim of this work was to identify in vivo-induced expressed immunogenic proteins using pooled sera from fish that have experienced photobacteriosis. In vivo induced immunogenic proteins included inosine-5'-monophosphate dehydrogenase (Impdh) and alkyl hydroperoxide reductase (AhpC), two proteins involved in peptide synthesis: serine hydroxymethyl transferase (Shmt) and alanyl-tRNA synthetase (AlaRS) and the non-ribosomal peptide synthetase involved in the synthesis of the siderophore piscibactin (Irp2)

Respuesta inmune en mucosas de piel y branquias de Solea senegalensis tras la alimentación con una dieta conteniendo Ulva ohnoi (5%)

Abstract In the search of the improvement of the feeding of the fish in the aquaculture, macroalgae seem to be a promising source of nutrients and bioactive substances. In the case of the genus Ulva, the effect of its inclusion in feed on the growth, tissues composition and the stress response of some fish species has been evaluated. However, it is necessary to evaluate the effects on the immune system, as its inclusion could modify the resistance to pathogens. In the present work, we have studied the response of the immune system at lysozyme expression level, cellular immune response genes, and inflammatory response genes in mucous of skin and sole gills (Solea senegalensis) fed with a diet supplemented in Ulva ohnoi (5%). Results obtained indicate absence of significant changes in the expression of assayed immune genes. Resumen En la búsqueda de la mejora de la alimentación de los peces en la acuicultura, las algas se presentan como una prometedora fuente de nutrientes y sustancias bioactivas. En el caso del género Ulva, se ha publicado el efecto de su inclusión en piensos sobre el crecimiento, la composición de los tejidos y la respuesta al estrés de algunas especies de interés acuícola. Sin embargo, es necesario evaluar los efectos en el sistema inmune, puesto que su inclusión podría modificar la resistencia a patógenos. En el presente trabajo se ha estudiado la respuesta del sistema inmune a nivel de expresión de lisozimas, genes de respuesta inmune celular, y genes de la respuesta inflamatoria en piel y branquias de lenguados (Solea senegalensis) alimentados con una dieta suplementada en Ulva ohnoi (5%). Los resultados indican que no se produce un cambio significativo en la expresión de estos grupos de genes.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Ministerio de Ciencia e Innovación (INIA) y FEDER (Ref. RTA2014 00023 C0202

Modulation of Intestinal Microbiota in Solea senegalensis Fed Low Dietary Level of Ulva ohnoi

Gastrointestinal (GI) microbiota has a relevant role in animal nutrition, modulation of the immune system and protection against pathogen invasion. Interest in algae as source of nutrients and functional ingredients for aquafeeds is increasing in order to substitute conventional feedstuffs by more sustainable resources. The diet is an important factor in the modulation of the microbiota composition, and functional ingredients have been proposed to shape the microbiota and contribute benefits to the host. However, fish microbiome research is still limited compared to other hosts. Solea senegalensis is a flat fish with high potential for aquaculture in South Europe. In this study, a characterization of the microbiome of S. senegalensis (GI) tract and the effects of feeding Ulva ohnoi supplemented diet has been carried out. Differences in the composition of the microbiota of anterior and posterior sections of S. senegalensis GI tract have been observed, Pseudomonas being more abundant in the anterior sections and Mycoplasmataceae the dominant taxa in the posterior GI tract sections. In addition, modulation of the GI microbiota of juvenile Senegalese sole fed for 45 days a diet containing low percentage of U. ohnoi has been observed in the present study. Microbiota of the anterior regions of the intestinal tract was mainly modulated, with higher abundance of Vibrio spp. in the GI tract of fish fed dietary U. ohnoi