聚乙烯吡咯烷酮对公猪精液冷冻的影响

试验旨在评价聚乙烯吡咯烷酮（polyvinylpyrrolidone，PVP）对公猪精液冷冻的影响。试验分为5组，分别为对照组（不添加PVP）和PVP处理组（在冷冻基础液中分别加入0.25%、0.50%、1.00%、2.00% PVP）。采用手握法采集松辽黑猪精液，用5种冷冻基础液稀释，在25 ℃平衡1 h，17 ℃平衡2 h，4 ℃平衡3 h后灌装于0.5 mL细管中，在液氮上方3 cm处熏蒸10 min，保存在液氮罐中30 d后进行检测。样本解冻后分别检测精子活力、质膜完整性、顶体完整性、线粒体活性、DNA完整性、过氧化氢酶（catalase，CAT）活性、超氧化物歧化酶（superoxide dismutase，SOD）活性、谷胱甘肽过氧化物酶（glutathioneperoxidase，GSH-Px）活性、活性氧簇（reactive oxygen species，ROS）水平及丙二醛（malondialdehyde，MDA）水平。结果显示，与对照组相比，冷冻基础液中添加0.50% PVP显著提高冻融后精子的活力、质膜完整性、顶体完整性、线粒体活性、CAT活性、SOD活性、GSH-Px活性（P<0.05），显著降低精子ROS和MDA水平（P<0.05）；与对照组相比，添加PVP有利于提高DNA完整性，但差异不显著（P>0.05）。因此，猪精液冷冻基础液中添加PVP可改善冻融后精子质量，添加0.50%效果最佳。

Effect of Polyvinylpyrrolidone on Cryopreservation of Boar Semen

The purpose of this study was to investigate the effect of polyvinylpyrrolidone (PVP) on boar semen freezing.There were five groups in the experiment:Control group (not add PVP) and PVP treatment groups (add 0.25%,0.50%,1.00%,and 2.00% PVP to the frozen base fluid).Collecting the semen of Songliao Black pig by hand,diluted with five frozen base solutions,equilibrated for 1 h at 25 ℃,2 h at 17 ℃,3 h at 4 ℃,then filled in 0.5 mL straw,fumigated 3 cm above liquid nitrogen for 10 min,stored in a liquid nitrogen tank for 30 d and tested.Sperm viability,plasma membrane integrity,acrosome integrity,mitochondrial activity,DNA integrity,catalase (CAT) activity,superoxide dismutase (SOD) activity,glutathione peroxidase (GSH-Px) activity,reactive oxygen species (ROS) level and malondialdehyde (MDA) level were tested after thawing.The results showed that compared with the control group,adding 0.50% PVP to the frozen base fluid could significantly improve the sperm viability,plasma membrane integrity,acrosome integrity,mitochondrial activity,CAT activity,SOD activity,GSH-Px activity (P<0.05);and significantly reduced the sperm ROS and MDA level (P<0.05).Adding PVP was beneficial to improve DNA integrity,but had no significant effect on DNA integrity compared with the control group (P>0.05).In conclusion,adding PVP to boar semen in the frozen base solution could improve the quality of sperm after freezing and thawing,the best concentration was 0.50%.