Potential uses of bacterin to prevent shrimp vibriosis

Enhancement of growth in tiger shrimp (Penaeus monodon) by oral bacterin prepared from Vibrio vulnificus has been previously reported. In this experiment, we repeated our trial of immersion delivery of bacterin, this time adjusting its concentration to 10% with pond water. Post-larvae 13 were immersed in the aerated bacterin for 2.5 h and their density was adjusted to 500 individuals/l of bacterin. Booster immersion was not administered. Twenty shrimp were captured randomly at 5-7-day intervals after treatment. The body length and weight of each shrimp were measured and the growth curves were plotted, demonstrating that shrimps grew faster in the immersion group than in the control group. This result disproves previous conjectures that post-larvae 13 are too young to be immunised by immersion application or that a single administration is insufficient.