Addition of chlorogenic acid and caffeine during the processing of cooled boar semen

ABSTRACT A study was conducted to evaluate the effect of chlorogenic acid (ChA) added pre-cooling and its combination with caffeine added during warming on cooled-stored boar semen parameters. Ten ejaculates were diluted in commercial extender with or without 4.5mg/ml ChA and stored at 15°C. After 0, 24 and 72 hours of storage, aliquots of these doses were taken and incubated at 37°C in the presence or absence of 8.0mM caffeine. Semen quality was evaluated after 10 and 120 minutes of incubation. The ChA increased (P <0.01) the sperm motility, viability, acrosomal integrity and the percentage of spermatozoa with high mitochondrial activity (PMHA), however, decreased (P <0.01) the malondialdehyde (MDA) concentration. Caffeine increased (P<0.05) the sperm motility, viability, PMHA and the MDA concentration and reduced (P <0.05) the acrosome integrity. When associated (ChA+caffeine), there was an increase (P <0.05) in sperm motility and viability, PMHA and acrosome integrity. The addition of ChA to the dilution medium improves the quality of the swine inseminating doses. The addition of caffeine during re-warming is only recommended when the semen is stored for prolonged periods (72h), and the inseminating dose should be used immediately after its addition.

摘要 本研究旨在评估预冷阶段添加绿原酸（chlorogenic acid, ChA），以及其与复温阶段添加的咖啡因联用对冷藏公猪精液参数的影响。选取10份公猪精液样本，分别用含或不含4.5mg/ml绿原酸的商用精液稀释剂进行稀释，于15℃条件下冷藏保存。在冷藏0、24及72小时后，分别取出各分组的等分试样，在添加或不添加8.0mM咖啡因的环境中于37℃孵育。孵育10分钟和120分钟后，对精液品质进行评估。绿原酸可极显著提升（P<0.01）精子活力、活率、顶体完整性及高线粒体活性精子百分比（percentage of spermatozoa with high mitochondrial activity, PMHA），同时极显著降低（P<0.01）丙二醛（malondialdehyde, MDA）浓度。咖啡因可显著提升（P<0.05）精子活力、活率、高线粒体活性精子百分比与丙二醛浓度，并显著降低（P<0.05）顶体完整性。二者联用时，精子活力、活率、高线粒体活性精子百分比及顶体完整性均显著提升（P<0.05）。在精液稀释液中添加绿原酸可改善公猪输精精液的品质。复温阶段添加咖啡因仅建议在精液长期冷藏（72小时）后使用，且添加后需即刻使用该输精样本。