Optimization of bull semen cryopreservation protocols using recombinant plant proteins as cryoprotective agents

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Semex Alliance is a Canadian industry specialised in bovine artificial insemination (AI) and reproductive biotechnology. They offer innovative solutions in reproduction and genetics at the international level. Canadian bull semen is exported around the world and during shipping is preserved by cryopreservation at temperatures below -150C. Current protocols for cryopreservation of bull semen have serious limitations that result in significant losses of viability and post-thaw fertility (PTF). The average industry PTF rate is about 30 to 50%. However, high rates of PTF are an important factor when dairy and cattle farmers procure semen for AI. Higher viability and PTF rates lead to higher success rates for AI. The company-specific research challenge is to develop innovative technology to improve cryopreservation protocols for dairy and beef semen, with the aim of achieving higher success rates for AI and reproductive biotechnology. Dr Averill-Bates' research team has developed innovative technology where recombinant proteins from winter wheat are used as cryoprotectants. These freezing tolerance-associated proteins are nature's way of dealing with extreme cold stresses. The objectives are to: 1) evaluate if a new generation of cryoprotective agents derived from plants can improve cryopreservation of bull semen, and 2) to understand the molecular mechanisms involved in freeze-thaw damage to spermatozoa. Canada is a huge producer of dairy and cattle, and is internationally renowned for the superior genetic quality of its bulls and for its innovative genetics programs. The development of innovative protocols for cryopreservation of bull semen that improve viability and PTF would represent a huge step forward for the AI industry. Any improvement to a company's PTF significantly improves their market share and return on investment. In addition, improved PTF increases return on investment for the dairy and cattle farmer end-users, where a 1-2% increase in PTF leads to significant impacts on operating costs. The distribution of high quality semen with advanced genetics is primordial for development of the dairy and beef industries, for international competitiveness, and for the Canadian animal agriculture economy.