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

Semex联盟是加拿大一家专门从事牛人工授精（AI）和生殖生物技术的行业。他们在国际层面上提供生殖和遗传学方面的创新解决方案。加拿大公牛的精液出口到世界各地，在运输过程中被低温保存在零下150摄氏度以下。目前的公牛精液冷冻保存方案有严重的局限性，导致生存能力和解冻后生育能力（PTF）的重大损失。行业平均PTF率约为30%至50%。然而，高PTF率是乳品和养牛户为AI获取精液时的一个重要因素。更高的生存能力和PTF率导致更高的人工智能成功率。该公司的具体研究挑战是开发创新技术，以改进奶牛和牛肉精液的冷冻保存方案，目的是提高人工智能和生殖生物技术的成功率。Averill-Bates博士的研究团队开发了一种创新技术，将冬小麦中的重组蛋白用作冷冻保护剂。这些与抗冻性相关的蛋白质是大自然应对极端寒冷压力的方式。目的是：1)评估从植物中提取的新一代冷冻保护剂是否能改善公牛精液的冷冻保存；2)了解冻融损伤精子的分子机制。加拿大是一个巨大的乳制品和奶牛生产国，并以其优良的公牛遗传质量和创新的遗传计划而享誉国际。开发创新的公牛精液冷冻保存方案，提高生存能力和PTF，将是人工智能行业向前迈出的一大步。对公司PTF的任何改进都会显著提高他们的市场份额和投资回报。此外，改善的PTF增加了奶牛和养牛户最终用户的投资回报，其中PTF增加1-2%会对运营成本产生重大影响。具有先进遗传技术的高质量精液的分布对乳制品和牛肉产业的发展、国际竞争力以及加拿大畜牧业经济的发展至关重要。

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.