Dietary Cordyceps militaris protects against Vibrio splendidus infection in sea cucumber Apostichopus japonicus. Issue 2 (August 2015)

• Record Type: Journal Article
• Authors: Sun, Yongxin; Du, Xingfan; Li, Shuying; Wen, Zhixin; Li, Yajie; Li, Xuejun; Meng, Nan; Mi, Rui; Ma, Shuhui; Sun, Aijie
• Is Part Of: Fish & shellfish immunology. Volume 45:Issue 2(2015:Aug.)
• Page Start: 964
• Page End: 971
• Publication Date: 2015-08
• Subjects: Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2015.05.053
• Languages: English
• ISSNs: 1050-4648

Abstract

<abstract xml:lang="en" abstract-type="author" id="abs0010"> <title id="sectitle0010">Abstract</title> <sec> <p id="abspara0010"> <italic>Vibrio splendidus</italic> is the common pathogen that causes infectious diseases widely spread in cultured sea cucumber in China. Therefore, we investigated the ability of <italic>Cordyceps militaris</italic> to protect against infection caused by <italic>V. splendidus</italic>. In this study, sea cucumbers were fed with a diet containing 0 (control), 1%, 2% or 3% <italic>C. militaris</italic> for 28 days, and subsequently challenged with <italic>V. splendidus</italic> by injection with 1.0 × 10<sup>9</sup> cfu per animal. Parameters of immune response such as phagocytosis (PC), lysozyme (LSZ) activity, superoxide dismutase (SOD) activity, alkaline phosphatase (AKP) activity and acid phosphatase (ACP) activity were determined on days 0, 1, 3, 5 and 7 after injection. The results showed that dietary <italic>C. militaris</italic> at a dose of 2% or 3% significantly up-regulated (<italic>P</italic> < 0.05) all the immune parameters on day 0. One day after injection with <italic>V. splendidus</italic>, all the immune indices except ACP exhibited a tendency to decrease and then increase again, returning to the initial level on days 5 and/or 7 after injection. All the immune parameters of those fed with <italic>C. militaris</italic> were found significantly higher (<italic>P</italic> < 0.05) than those of the control group on day 1 after injection. Only LSZ activity of those fed with 1%- or 3%-<italic>C. militaris</italic> diet on day 5 showed significantly increases (<italic>P</italic> < 0.05) than the controls. As for ACP activity, the values remained steady with time, but with significant increase (<italic>P</italic> < 0.05) seen in sea cucumbers fed with 2%-<italic>C. militaris</italic> diet, and lasted for up to 7 days after <italic>V. splendidus</italic> injection. The cumulative mortality of sea cucumbers fed with the basal diet followed <italic>V. splendidus</italic> infection was significantly higher (<italic>P</italic> < 0.05) than those fed with 2% and 3% <italic>C. militaris</italic> diet. Under the experimental conditions, dietary <italic>C. militaris</italic> could enhance the immune responses of <italic>Apostichopus japonicus</italic> and improve its resistance to infection by <italic>V. splendidus</italic>.</p> </sec> </abstract>