Successful production of black tiger shrimp in Australia with new mode of delivery of probiotics: Moving away from delivery via feed to manage bacterial pathogens

Managing opportunistic bacterial pathogens such as Vibrio species is critical for biosecurity and farm productivity in shrimp aquaculture. Traditional on-farm probiotic top-coating of commercial feeds is labor-intensive and prone to dosage inconsistency. To evaluate an alternative direct delivery method, a commercial farm trial was conducted at Pacific Reef Fisheries in Queensland, Australia, comparing seven treatment ponds fed Bacillus-coated slow-sinking wafers against seven control ponds. The trial stocked approximately 8.5 million black tiger shrimp (Penaeus monodon) postlarvae across 12 hectares. Probiotic wafers were applied as a percentage of feed during the first 70 days of culture (DOC 0–70). Probiotic treatment accelerated shrimp growth, resulting in a 9% higher average body weight by DOC 107 and enabling earlier partial harvests starting on DOC 108 compared to DOC 117 in controls. Across an average 155-day cycle, applying probiotic wafers increased final survival by 21%, boosted total productivity by 19% (from 9.6 to 11.4 tonnes/ha), and improved feed conversion ratio (FCR) by 6% (from 1.91 to 1.80), saving 115 kg of feed per tonne of shrimp produced.