title: The response of fish to immunostimulant diets.
abstract: In order to maintain fish health and to improve performance immunostimulants have been used as dietary additives to improve weight gain, feed efficiency, and/or disease resistance in cultured fish. In aquaculture, non-specific immunostimulants have been widely used probably due to the limited knowledge of the immune response in fish and the ease of their application. Many studies have been carried out to assess the effect of dietary immunostimulants in fish including algal derivatives, herb and plant extract containing diets using a wide range of downstream analytical techniques. Many immunostimulants are based upon tradition and folklore transferred through generations and specific to certain geographical regions rather than known biological properties. However, there are studies in which it is possible to observe a clear and direct dose-dependent stimulatory effect upon the immune system. Other dietary supplements used contain PAMPs (Pathogen Associated Molecular Patterns) as immunostimulants whose recognition depends upon PRR (pathogen recognition receptor) interactions including the TLRs (Toll-like receptor). Despite the growing interest in the use of immunostimulants across the aquaculture industry the underlying mechanisms of ligand recognition, extract composition and activation of the fish immune response remains fragmented. In this review we focus upon the last 15 years of studies addressing the assessment of: (1) plant, herb and algae extracts; and (2) PAMPs, upon non-specific immune parameters of activation and immunostimulant diet efficacy.
authors.affiliation: Institut de Biotecnologia i Biomedicina, Universitat Autonoma de Barcelona, 08193 Bellaterra, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Vallejos-Vidal
authors.affiliation: Department of Cell Biology, Physiology and Immunology, Universitat Autonoma de Barcelona, 08193 Bellaterra, Spain.
authors.forename: Felipe
authors.initials: F
authors.lastname: Reyes-López
authors.affiliation: Department of Cell Biology, Physiology and Immunology, Universitat Autonoma de Barcelona, 08193 Bellaterra, Spain.
authors.forename: Mariana
authors.initials: M
authors.lastname: Teles
authors.affiliation: Institute of Aquaculture, University of Stirling, FK9 4LA Stirling, UK. Electronic address: Simon.MacKenzie@stir.ac.uk.
authors.forename: Simon
authors.initials: S
authors.lastname: MacKenzie
mesh_terms: D000276:Adjuvants, Immunologic; D000818:Animals; D017756:Aquaculture; D004032:Diet / Q000662:veterinary*; D005399:Fishes / Q000276:immunology*; D007113:Immunity, Innate; D019684:Magnoliopsida / Q000737:chemistry; D058086:Microalgae / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D012624:Seaweed / Q000737:chemistry
chemical_list: D000276:Adjuvants, Immunologic
keywords: Algae; Fish immunostimulant diets; Herbs; Immune response; PAMPs; Plant extracts