Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA.
Department of Animal Science, University of Ibadan, Ibadan 200005, Nigeria.
J Anim Sci. 2023 Jan 3;101. doi: 10.1093/jas/skac384.
Natural honey has been successfully used in the preservation of mammalian gametes because of its beneficial properties. The objectives of this study were to determine the inclusion level of honey in extender for improving boar semen quality before freezing and to investigate the effects of honey inclusion in extender and freezing media on post-thaw quality of frozen-thawed boar semen samples. Ejaculates from six terminally crossbred boars were collected using the gloved-hand technique for two experiments. Experiment 1 was a randomized block design, evaluating four inclusion levels of honey in boar semen extender [Control (0H)-Androhep Plus or Androhep Plus with 0.25%, 0.50%, and 0.75% honey (0.25H, 0.50H, and 0.75H respectively)]. Ejaculates were pooled, aliquoted according to treatments, and cooled for 24 h at 17 ºC. The results of this experiment were used to determine inclusion levels in exp. 2. Experiment 2 was a 2 x ×3 factorial design, evaluating the inclusion of honey in boar semen extender and freezing media. Semen samples from individual boars were cooled in extender with or without honey (C0: Androhep Plus; C1: Androhep Plus + 0.25% honey). After 24 h, semen samples were evaluated, diluted in lactose-egg yolk (LEY) media, and one of three freezing media types; F0: 93% LEY + 6% glycerol + 1% Equex-STM Paste (ESP); F1: 93% LEY + (3% glycerol and 3% honey) + 1% ESP; and F2: 93% LEY + 6% glycerol + (0.5% ESP and 0.5% honey). Samples were frozen in 0.5 mL straws using a controlled-rate freezer and stored in liquid nitrogen. In exp. 1, 0.25H and 0.50H improved motility (P = 0.033) and progressive motility (P = 0.001) of cooled boar semen. Nevertheless, 0.25H was selected for exp. 2. In exp. 2, post-thaw motility and progressive motility were highest (P < 0.05) in C0F2 but not different from C1F2. Morphologically normal cells and acrosomes were higher with all inclusion levels of honey (P < 0.05). In conclusion, 0.25% and 0.50% inclusion of honey in Androhep Plus improves motility and progressive motility of cooled boar semen samples after 24 h. Supplementing Androhep Plus with 0.25% honey maintains higher normal sperm cells and acrosomes of cryopreserved boar semen. Replacing 50% Equex-STM paste with honey in freezing media improves post-thaw sperm motility, progressive motility, percentage of normal sperm, and acrosome of cryopreserved boar semen.
天然蜂蜜因其有益特性已成功用于保存哺乳动物配子。本研究的目的是确定在冷冻前在 extender 中添加蜂蜜的水平，以提高猪精液的质量，并研究在 extender 和冷冻介质中添加蜂蜜对冷冻解冻猪精液样品解冻后质量的影响。使用手套技术从 6 头终端杂交公猪中收集精液进行了两项实验。实验 1 采用随机区组设计，评估了猪精液 extender 中蜂蜜的四个添加水平[对照（0H）-Androhep Plus 或含有 0.25%、0.50%和 0.75%蜂蜜的 Androhep Plus（分别为 0.25H、0.50H 和 0.75H）]。精液混合，根据处理进行等分，并在 17°C 下冷却 24 小时。该实验的结果用于确定实验 2 中的添加水平。实验 2 是一个 2×3 析因设计，评估了在猪精液 extender 和冷冻介质中添加蜂蜜。个体公猪的精液在含有或不含有蜂蜜的 extender 中冷却（C0：Androhep Plus；C1：Androhep Plus + 0.25%蜂蜜）。24 小时后，评估精液样本，在乳糖-卵黄（LEY）介质中稀释，然后使用三种冷冻介质类型之一；F0：93%LEY+6%甘油+1%Equex-STM 糊剂（ESP）；F1：93%LEY+（3%甘油和 3%蜂蜜）+1%ESP；和 F2：93%LEY+6%甘油+（0.5%ESP 和 0.5%蜂蜜）。使用控速冷冻机将样品冷冻在 0.5 毫升吸管中，并储存在液氮中。在实验 1 中，0.25H 和 0.50H 提高了冷却猪精液的运动性（P=0.033）和直线运动性（P=0.001）。然而，0.25H 被选为实验 2。在实验 2 中，C0F2 的解冻后运动性和直线运动性最高（P<0.05），但与 C1F2 没有差异。所有蜂蜜添加水平的形态正常细胞和顶体都更高（P<0.05）。总之，在 Androhep Plus 中添加 0.25%和 0.50%的蜂蜜可提高冷却 24 小时后的猪精液样本的运动性和直线运动性。在 Androhep Plus 中添加 0.25%的蜂蜜可维持更高比例的冷冻保存猪精液中的正常精子细胞和顶体。用冷冻介质中的 50%Equex-STM 糊剂代替蜂蜜可提高冷冻解冻猪精液的解冻后精子运动性、直线运动性、正常精子比例和顶体。
