Thymol and Carvacrol Affect Hybrid Tilapia through the Combination of Direct Stimulation and an Intestinal Microbiota-Mediated Effect: Insights from a Germ-Free Zebrafish Model.

Background: Essential oils (EOs) are commonly used as animal feed additives. Information is lacking on the mechanisms driving the beneficial effects of EOs in animals, especially the role played by the intestinal microbiota of the host.

Objective: The purpose of this study was to clarify the relative contribution of direct effects of EOs on the physiology and immune system of tilapia and indirect effects mediated by the intestinal microbiota by using a germ-free zebrafish model.

The effects of feeding β-glucan to Pangasianodon hypophthalmus on immune gene expression and resistance to Edwardsiella ictaluri.

Pangasianodon hypophthalmus (striped catfish) is an important aquaculture species and intensification of farming has increased disease problems, particularly Edwardsiella ictaluri. The effects of feeding β-glucans on immune gene expression and resistance to E. ictaluri in P.

The effects of feeding immunostimulant β-glucan on the immune response of Pangasianodon hypophthalmus.

Immunostimulants are food additives used by the aquaculture industry to enhance the immune response of fish, and although β-glucans are now commonly used for this purpose in aquaculture, little is known about their effects on the immune response of Pangasianodon hypophthalmus. Thus, a variety of immune parameters (e.g.

Optimisation and standardisation of functional immune assays for striped catfish (Pangasianodon hypophthalmus) to compare their immune response to live and heat killed Aeromonas hydrophila as models of infection and vaccination.

Aquaculture production of Pangasianodon hypophthalmus is growing rapidly in South East Asia, especially in Vietnam. As it is a relatively new aquaculture species there are few reports evaluating its immune response to pathogens. Thus, functional assays for P.

Enhanced survival of shrimp, Penaeus (Marsupenaeus) japonicus from white spot syndrome disease after oral administration of recombinant VP28 expressed in Brevibacillus brevis.

White spot syndrome virus (WSSV) disease is a major threat to shrimp culture worldwide. Here, we assessed the efficacy of the oral administration of purified recombinant VP28, an envelope protein of WSSV, expressed in a Gram-positive bacterium, Brevibacillus brevis, in providing protection in shrimp, Penaeus japonicus, upon challenge with WSSV. Juvenile shrimp (2-3g in body weight) fed with pellets containing purified recombinant VP28 (50microg/shrimp) for 2 weeks showed significantly higher survival rates than control groups when challenged with the virus at 3 days after the last day of feeding.

A soluble nonglycosylated recombinant infectious hematopoietic necrosis virus (IHNV) G-protein induces IFNs in rainbow trout (Oncorhynchus mykiss).

Viral glycoproteins interact with cell-surface receptors to mediate virus entry and innate immune system activation. We found that a soluble recombinant infectious hematopoietic necrosis virus G-protein (rIHNV-G) stimulated an early innate immune response mediated by proinflammatory cytokines, IFN1 and IFN-gamma in rainbow trout (Oncorhynchus mykiss) fry. Expression of both IFN1 and IFN-gamma mRNA transcripts was an early event and was rIHNV-G dose-dependent.

Innate immunomodulation with recombinant interferon-alpha enhances resistance of rainbow trout (Oncorhynchus mykiss) to infectious hematopoietic necrosis virus.

We examined the in vivo immunostimulatory effects of a recombinant Atlantic salmon (Salmo salar) interferon-alpha2 (rSasaIFN-alpha2). The mature rSasaIFN-alpha2, expressed and purified from Escherichia coli, was administered to rainbow trout (Oncorhynchus mykiss) via the oral, immersion, or intraperitoneal (IP) injection route. Injection of rSasaIFN-alpha2 at 0.

Biological characterisation of a recombinant Atlantic salmon type I interferon synthesized in Escherichia coli.

Type I (alpha/beta) interferons (IFNs) are a family of cytokines that stimulate the expression of numerous proteins that mediate an antiviral state in uninfected cells. Two Atlantic salmon (Salmo salar) IFN-alpha (SasaIFN-alpha1 & 2) genes have previously been cloned and both were found to contain a putative N-linked glycosylation site. Recombinant SasaIFN-alpha1 (rSasaIFN-alpha1) produced in eukaryotic systems has repeatedly been shown to confer antiviral properties.

Functional characterisation of the Japanese flounder, Paralichthys olivaceus, Mx promoter.

The Japanese flounder, Paralichthys olivaceus, genome appears to encode a single Mx gene based on Southern blotting and previous cDNA studies. The 5' flanking region of the Japanese flounder Mx gene was cloned and analysed for its regulatory regions. A TATA box (-24 to -30), two interferon-stimulated response elements (ISREs) (-69 to -80 and -508 to -521) and two Sp1 sites (-563 to -572 and -994 to -1003) were identified relative to the transcription start site.