Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80526, USA.
Membrane Protective Technologies Inc., Fort Collins, CO 80524, USA.
J Anim Sci. 2022 Jul 1;100(7). doi: 10.1093/jas/skac169.
Cryopreservation of sperm is a routine technology in many livestock species, but not in swine. Frozen sperm must result in acceptable conception rates and produce 11 to 12 piglets/litter to be competitive with traditional cooled semen. The development of an extender that results in high post-thaw sperm quality and acceptable litter size requires the identification of factors that markedly affect post-thaw semen quality. The present study aims to first identify factors in boar sperm cryopreservation that significantly affect post-thaw sperm quality using an efficient, cost-effective, and relatively rapid approach. The Plackett-Burman experimental design is ideal for the screening of factors at their extreme, greatly reducing the amount of time and resources needed for a follow-up, full factorial design. Using commercial semen, a 9-factor, 12-run Plackett-Burman design was used on 10 boars split between 12 treatments. Through this method, glycerol concentration, cooling rate, antioxidant supplementation with GameteGuard (Membrane Protective Technologies, Inc. Fort Collins, CO), and straw size were identified as highly influential factors that affect post-thaw sperm quality. Extender type, starting osmolality, sodium dodecyl sulfate addition, and stepwise addition of glycerol were also influential for some but not all post-thaw sperm parameters (P < 0.05). Equilibration time in the straws before freezing was determined to have no impact on post-thaw sperm quality parameters. Using the Plackett-Burman design, it can be concluded that four of the nine factors warrant detailed investigation in full factorial experiments in the development of boar sperm cryopreservation extenders.
精子的冷冻保存是许多家畜物种的常规技术，但在猪中并非如此。冷冻精子必须产生可接受的受孕率，并产生 11 到 12 头仔猪/窝，才能与传统的冷却精液竞争。开发一种能够产生高解冻后精子质量和可接受的窝产仔数的 extender，需要确定明显影响解冻后精液质量的因素。本研究旨在首先使用高效、经济且相对快速的方法，确定影响猪精子冷冻保存后精子质量的因素。Plackett-Burman 实验设计非常适合在极端条件下筛选因素，可以大大减少后续全面实验设计所需的时间和资源。使用商业精液，在 10 头公猪之间进行了 9 因素 12 次运行的 Plackett-Burman 设计，分为 12 种处理。通过这种方法，甘油浓度、冷却速率、抗氧化剂补充 GameteGuard（膜保护技术公司，科罗拉多州福尔斯）和 straw 大小被确定为影响解冻后精子质量的高度影响因素。 extender 类型、起始渗透压、添加十二烷基硫酸钠以及逐步添加甘油对某些但不是所有解冻后精子参数也有影响（P < 0.05）。在冷冻前 straw 中的平衡时间被确定对解冻后精子质量参数没有影响。使用 Plackett-Burman 设计，可以得出结论，在开发猪精子冷冻保存 extender 的全面实验中，九个因素中有四个值得进行详细研究。
