Commercial-scale sperm cryopreservation for blue catfish
E. HU - SCHOOL OF RENEWABLE NATURAL RESOURCES
The U.S. catfish industry has been in decline as fuel and feed prices have risen. However, production of hybrid catfish (channel catfish female × blue catfish male) has remained strong. The demand for artificial spawning to produce hybrid catfish fry has increased, and now limitation of broodstock males has become a critical constraint. Sperm cryopreservation technology provides a solution to storage and distribution problems with sperm of blue catfish without losing fertility. Because small laboratory-level cryopreservation cannot satisfy commercial-scale hybrid fry production, our goal was to develop a manufacturing line capability that achieves high-throughput sperm cryopreservation for blue catfish. The objectives were to: 1) adapt automation to the cryopreservation process; 2) apply cryopreserved sperm at a commercial-scale; 3) provide evaluation methods for the cryopreserved product; 4) educate potential users about cryopreserved germplasm; 5) establish a quality assurance plan for the manufacturing line, and 6) model production by use of computer simulation software.
There are several automated systems designed for sperm cryopreservation of mammals. We adopted the MAPI system from CryoBioSystem (Paris, France) to ensure high biosecurity and developed a model process. In cooperation with the Baxter Land Company (Dermott, AR) and the USDA Catfish Genetics Research Unit (Stoneville, MS), we processed fish each year from 2009 to 2012. In 2010 and 2011, cryopreserved sperm was evaluated in the commercial hatchery of Baxter Land Company and 200,000 hybrid fry were produced each day for 7 days. Evaluation of cryopreserved fish sperm cannot be based on traditional mammalian conception rates, and thus fertilization of specific numbers of eggs and other parameters (e.g. motility, membrane integrity) were used for evaluation. Meanwhile, educational user manuals were developed to assist public acceptance of the new products. As an automated production line, sperm processing was under constant quality monitoring with established quality characteristics specifications. Computer simulation models were built to represent the production line, expand throughput, increase efficiency, and remove bottlenecks in the process (Figure 1). This project provides a comprehensive platform for high-throughput cryopreservation of blue catfish sperm and opens the door for future commercialization of this technology.