SBIR-STTR Award

Aquaculture expansion is a global imperative to address food security. Slow maturation of highly desirable marine carnivorous finfish species is a major hindrance in the pursuit of genetic improvement through selective breeding. Female Seriola (yellowtail) take four years to reach maturity. The goal of this work is to identify methods of inducing precocious puberty in juvenile S.rivoliana. Phase I includes 6-month trials of hormonal application in 1-year-old S.rivoliana: one treatment group of 17β-estradiol (E2) one of E2 and insulin-like growth factor 1 (IGF1) and one control. Additionally we will analyze brain tissue of immature pubescent and mature specimens to identify micro RNAs associated with the onset of puberty for use in subsequent study. We anticipate up regulation of estrogen receptors in the brain and increased growth rate. These criteria are precursors to female puberty indicating feasibility of achieving precocious puberty in Phase II. If validated these data will provide the foundation of a puberty induction regimen for S.rivoliana. Accelerated maturation is a commercially important ability with implications for selective breeding. Coupled with Kampachi Farms' ongoing identification of genetic markers for desirable traits in Seriola the proposed effort will allow more rapid production of broodstock with genotypes tailored to efficient production and decreased ecological footprint (ie. through tolerance of plant-based proteins). This research may be commercialized through Kampachi Farms' production partners and selling of genetically-improved broodstock for Seriola growers worldwide.

The proposed work directly responds to USDA SBIR Research Priority 8.7 Aquaculture by developing methods to accelerate maturity in Seriola rivoliana (a high-value marine finfish). This will reduce generation time allowing for accelerated selective breeding programs. The objectives of Phase II are to use hormonal and molecular tools to induce puberty and yield reproductively mature broodfish at the earliest time possible. This work targets brood stock therefore no hormone-treated fish will be destined for human consumption. To effectively accelerate S. rivoliana puberty we have chosen three hormonal treatments that we believe will condition the brain for earlier maturity induce onset of ovarian development and vitellogenesis and accelerate overall growth rate. A series of trials will be conducted over the two-year period. Initial work will refine the dose and administration of hormonal implants. Later twosix-month long trials will test and refine treatments. By analyzing levels of hormones in the brain and liver and by comparing gonadal and somatic growth between treated fish and un-treated controls we will identify if the methods are successful. The materials and procedures developed during this work can be used by the applicant (Ocean Era Inc) and be licensed to other Serial producers around the world.