title: Selection of Vibrio harveyi-resistant Litopenaeus vannamei via a three-round challenge selection with a pathogenic strain of V. harveyi.
abstract: To obtain Vibrio harveyi-resistant Litopenaeus vannamei shrimp used for study on immune response of shrimp avoid vibriosis, a three-round challenge selection procedure was applied. In this procedure, resistant shrimp were selected gradually via three rounds challenge experiment with a pathogenic strain of V. harveyi at a median and controllable lethal dose of 96-h LD50 (the median lethal dose). After this procedure, the cumulative mortality of selected shrimp during 96 h after injection of V. harveyi at 2.0 × 10(6) cfu shrimp(-1) significantly decreased from 93.3% to 26.7%, the hours of beginning of death and the hours of attaining of the maximum cumulative mortality of shrimp prolonged from 4 h and 10 h to 8 h and 24 h, respectively. The LD50 of 6 h, 12 h, 24 h, 48 h and 96 h of selected shrimp significantly increased to 1.4 ± 0.1 × 10(7) (p < 0.01), 5.5 ± 0.4 × 10(6) (p < 0.01), 3.1 ± 0.2 × 10(6) (p < 0.01), 2.7 ± 0.1 × 10(6) (p < 0.01) and 2.7 ± 0.1 × 10(6) cfu shrimp(-1) (p < 0.01), about 15.9, 15.3, 9.4, 10.0 and 10.4 times of that of normal shrimp, respectively. In conclusion, the resistance of shrimp to Vibrio significantly increased after the three-round challenge selection procedure.
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, No. 22 Xinong Road, Yangling, Shaanxi 712100, China.
authors.forename: Hai-Hong
authors.initials: HH
authors.lastname: Huang
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Liu
authors.forename: Jian-Hai
authors.initials: JH
authors.lastname: Xiang
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
mesh_terms: D000818:Animals; D017756:Aquaculture; D007113:Immunity, Innate; D007928:Lethal Dose 50; D033561:Penaeidae / Q000276:immunology* / Q000382:microbiology*; D014733:Vibrio / Q000502:physiology*
keywords: Challenge; LD50; Litopenaeus vannamei; Resistance; SSS; Selection; TCBS; TSB; TSV; Taura syndrome virus; Vibrio harveyi; WSSV; shrimp salt solution; the median lethal dose; thiosulfate citrate bile salts sucrose plate; tryptic soy broth; white spot syndrome virus