Please use this identifier to cite or link to this item: http://hdl.handle.net/1893/27935
Appears in Collections:Aquaculture Journal Articles
Peer Review Status: Refereed
Title: Streptococcus agalactiae infection kills red tilapia with chronic Francisella noatunensis infection more rapidly than the fish without the infection
Author(s): Sirimanapong, Wanna
Thompson, Kim D
Shinn, Andrew P
Adams, Alexandra
Withyachumnarnkul, Boonsirm
Contact Email: alexandra.adams@stir.ac.uk
Keywords: Francisella noatunensis subsp. orientalis
Streptococcus agalactiae
Red tilapia
Francisellosis
Streptococcosis
Sequential infections
Bacterial pathogens
Issue Date: 31-Oct-2018
Citation: Sirimanapong W, Thompson KD, Shinn AP, Adams A & Withyachumnarnkul B (2018) Streptococcus agalactiae infection kills red tilapia with chronic Francisella noatunensis infection more rapidly than the fish without the infection. Fish and Shellfish Immunology, 81, pp. 221-232. https://doi.org/10.1016/j.fsi.2018.07.022.
Abstract: In this study we examined the effect that a Francisella noatunensis (Fno) infection had on hybrid red tilapia (Oreochromis niloticus × Oreochromis mossambicus) subsquently infected with Streptococcus agalactiae. A variety of hemato-immunological parameters (haematocrit, total red blood cell count, mean corpuscular volume, total white blood and differential cell counts, total plasma protein, plasma lysozyme and plasma peroxidase activities, and respiratory burst and phagocytic activities of head-kidney macrophages) were measured in hybrid red tilapia that had been previously exposed to an Fno outbreak in a tilapia grow-out farm. The head-kidneys of these apparently healthy survivors, when checked by PCR were found to be Fno-positive with hemato-immunological parameters that were similar to fish without an a priori infection. The only exception was the percentage lymphocyte count in the peripheral blood, which was slightly, but significantly, lower in the Fno-infected fish, compared to those without the infection. When experimentally infected with S. agalactiae, the Fno-infected fish died more rapidly and at a significantly higher rate than fish without the infection. During the challenge, the hemato-immunological parameters of both groups of fish were very similar, although the Fno-infected fish, challanged with S. agalactiae expressed significantly higher plasma lysozyme and peroxidase activities, and their head kidney macrophages had significantly higher respiratory burst activity compared to non-Fno-infected fish challanged with S. agalactiae. The only two parameters for which Fno-infected fish showed significantly lower expressions than that of their non-infected counterparts were haematocrit and total red blood cell count. The cause of the rapidity and higher rates of mortality observed in the Fno-infected fish when challenged with S. agalactiae is unknown; but it may be due to a reduced erythropoiesis capability within the head-kidney because of the presence of Fno.
DOI Link: 10.1016/j.fsi.2018.07.022
Rights: This item has been embargoed for a period. During the embargo please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author. You can only request a copy if you wish to use this work for your own research or private study. Accepted refereed manuscript of: Sirimanapong W, Thompson KD, Shinn AP, Adams A & Withyachumnarnkul B (2018) Streptococcus agalactiae infection kills red tilapia with chronic Francisella noatunensis infection more rapidly than the fish without the infection. Fish and Shellfish Immunology, 81, pp. 221-232. DOI: https://doi.org/10.1016/j.fsi.2018.07.022 © 2018, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/

Files in This Item:
File Description SizeFormat 
Revised manuscript_4-7-2018.pdfFulltext - Accepted Version2.87 MBAdobe PDFView/Open



This item is protected by original copyright



Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

If you believe that any material held in STORRE infringes copyright, please contact library@stir.ac.uk providing details and we will remove the Work from public display in STORRE and investigate your claim.