Identification and pathogenicity of Vibrio parahaemolyticus isolates and immune responses of Penaeus (Litopenaeus) vannamei (Boone)

详细信息    查看全文

• 作者：X P Hong ; D Xu ; Y Zhuo ; H Q Liu and L Q Lu
• 刊名：Journal of Fish Diseases
• 出版年：2016
• 出版时间：September 2016
• 年：2016
• 卷：39
• 期：9
• 页码：1085-1097
• 全文大小：1328K
• ISSN：1365-2761

文摘

Five different Vibrio parahaemolyticus strains (SH8, SH108, SH58, AH5 and GD10) isolated from the hepatopancreas of moribund shrimp in farms of mainland China were identified and capable of inducing massive mortality of Penaeus (Litopenaeus) vannamei. The immersion challenge results with five isolates indicated variance of virulence, while only GD10 caused massive sloughing of tubule epithelial cells which was recognized as the most significant symptom of AHPND. Differences in immune responses were detected of P. vannamei during 48 h post-infection (p.i.) by injection or immersion challenge with V. parahaemolyticus (SH8, SH108 and GD10) isolates. When injected SH8 and SH108 isolates, the expression of lysozyme (LSZ) showing statistically significant upregulation at 16 and 48 h p.i. and that of Toll-like receptors (TLR) showed statistically significant upregulation at 48 h p.i. When immersion challenge with the GD10 isolate, TLR were upregulated after 8 h p.i. challenge with 10⁴ cfu mL⁻¹; however, LSZ was downregulated when challenged with 10³ cfu mL⁻¹. The results suggested that LSZ and TLR serve as crucial molecular markers of innate immunity in shrimp against V. parahaemolyticus infection. LSZ is a vital marker for acute bacterial infection, while TLR serves as a crucial marker for chronic infection.