Determining Ovarian Maturity in Farmed Sturgeon 1 (Acipenser transmontanus) for Caviar Production Using Fourier Transform Infrared Spectroscopy (FT-IR)

Abstract

Ovarian maturity of white sturgeon (Acipenser transmontanus, Acipenseridae) farmed in California (Sterling Caviar, LLC) (N=400) and Idaho (Fish Breeders and Blind Canyon Aqua Ranch) (N=143) was determined by correlating blood plasma spectral features [(Fourier transform infrared (FT-IR, 4000-400 cm -1 ) spectroscopy] with oocyte polarization index (PI), an index of germinal vesicle migration. A total of ~20,000 spectra were collected over a period of four years (2007, 2008, 2009 and 2010). Mathematical models could predict maturity in fish at a later year of harvest (i.e., 2010) and at either the California or Idaho production sites. PI values of 0.10, 0.15, and 0.20 were selected for segregating fish into subgroups based on ovarian maturity. Spectral features for specific proteins, lipids, carbohydrates and nucleic acids were related to fish maturity stages. Mathematical models could predict the actual PI values based on plasma spectral features in fish from 2010 based on models developed and validated from fish harvested in [2007][2008][2009]. These models worked equally well whether the fish were raised in California or Idaho. This research indicates that infrared spectroscopy provides a rapid and less invasive method to segregate sturgeon females according to maturity levels and has the potential to substitute for the traditional surgical biopsy to determine stage of maturity.