*** 96-61609 Shleser This Small Business Innovative Research (SBIR) Phase I project focuses on genetic improvement of the black tiger shrimp, Penaeus monodon. This species represents 75% of the world production of farmed shrimp, valued at more than 3 billion dollars per year. Selective breeding of this shrimp for performance in a farming environment is expected to improve profitability. Phase I will produce genetically identifiable Specific Pathogen Free P. monodon stocks, that can be selectively bred for improved farming performance. Polymerase Chain Reaction (PCR) amplification of introns in conserved nuclear genes using universal PCR primers will be applied to differentiate individuals of closely related populations of marine shrimp. This method will be used to evaluate captive populations of P.monodon to identify family lines for the breeding program. The commercial application is in a genetically improved broodstock and post larvae for export of shrimp throughout the world. ***