Citation Sirimanapong W, Thompson KD, Ooi EL, Bekaert M, Collet B, Taggart J, Bron J, Green D, Shinn A, Adams A & Leaver M (2015) The effects of feeding β-glucan to Pangasianodon hypophthalmus on immune gene expression and resistance to Edwardsiella ictaluri. Fish and Shellfish Immunology, 47 (1), pp. 595-605. https://doi.org/10.1016/j.fsi.2015.09.042
Abstract 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.hypophthalmus were explored. Fish were fed 0.1% fungal-derived β-glucan or 0.1% commercial yeast-derived β-glucan or a basal control diet without glucan. After 14 days of feeding, the mRNA expression of immune genes (transferrin, C-reactive protein, precerebellin-like protein, Complement C3 and factor B, 2a MHC class II and interleukin-1beta) in liver, kidney and spleen were determined. Following this fish from each of the three diet treatment groups were infected with E.ictaluri and further gene expression measured 24h post-infection (h.p.i.), while the remaining fish were monitored over 2 weeks for mortalities. Cumulative percentage mortality at 14 days post-infection (d.p.i.) was less in β-glucan fed fish compared to controls. There was no difference in gene expression between dietary groups after feeding for 14 days, but there was a clear difference between infected and uninfected fish at 24h.p.i., and based on principal component analysis β-glucans stimulated the overall expression of immune genes in the liver, kidney and spleen at 24h.p.i.