Department of Animal Biotechnology, Animal Production Research Institute, Agriculture Research Center, Dokki, Giza, Egypt.
Department of Animal Production, Faculty of Agriculture, Cairo University, Giza, Egypt.
Poult Sci. 2024 Nov;103(11):104190. doi: 10.1016/j.psj.2024.104190. Epub 2024 Aug 8.
Cryopreservation of rooster semen is essential for conserving genetic resources, genetic improvement, and increasing productivity. However, the nature of avian sperm presents a global issue in ensuring superior frozen semen for artificial insemination. Thus, the present study aimed to evaluate the impact of using dimethylacetamide (DMA), dimethyl sulfoxide (DMSO), and ethylene glycol (EG) as cryoprotectants on post-thawed sperm motility, quality, antioxidant indicators, and fertilizing capacity. Twice a week, fresh semen ejaculates were collected from 15 adult roosters and immediately evaluated to constitute a pool from clean and qualified samples. The pooled semen was further diluted at a ratio of 1:2 (v/v) with an extender and then subjected to a freezing protocol in a liquid nitrogen vapor after adding a cryoprotectant solution containing 6% of either DMA, DMSO, or EG, respectively. After thawing, characteristics of sperm motion, quality, antioxidants, and fertilizing ability were evaluated and compared to fresh and cooled semen as controls. The results demonstrated that semen cooling negatively affected some parameters of sperm motility, quality, antioxidant biomarkers, and fertility. In comparison to the DMSO and EG groups, employing DMA considerably (P < 0.05) raised the percentages of sperm progressive motility, viability, plasma membrane intactness, and DNA integrity. The DMA group showed a significant increase in the catalase and glutathione reduced antioxidant enzyme activity and a reduction in nitric oxide and lipid peroxidation. After artificial insemination, the DMA and DMSO groups exhibited considerably (P < 0.05) better rates of hatchability and fertility than the EG group. It is concluded that freezing extenders containing 6% DMA is better than DMSO or EG to improve the post thaw semen quality and fertility in chickens.
鸡精液的冷冻保存对于保存遗传资源、遗传改良和提高生产力至关重要。然而，禽类精子的性质在确保用于人工授精的优质冷冻精液方面存在全球性问题。因此，本研究旨在评估使用二甲基乙酰胺（DMA）、二甲基亚砜（DMSO）和乙二醇（EG）作为冷冻保护剂对解冻后精子活力、质量、抗氧化指标和受精能力的影响。每周两次，从 15 只成年公鸡中采集新鲜精液射精，并立即评估构成来自清洁和合格样本的池。将混合精液以 1:2（v/v）的比例与稀释液进一步稀释，然后在添加含有 6%DMA、DMSO 或 EG 的冷冻保护剂溶液后，在液氮蒸气中进行冷冻程序。解冻后，评估精子运动、质量、抗氧化剂和受精能力的特征，并与新鲜和冷却精液作为对照进行比较。结果表明，精液冷却对精子运动、质量、抗氧化生物标志物和生育能力的一些参数产生负面影响。与 DMSO 和 EG 组相比，使用 DMA 可显著（P<0.05）提高精子前向运动、活力、质膜完整性和 DNA 完整性的百分比。DMA 组显示出过氧化氢酶和还原型谷胱甘肽抗氧化酶活性的显著增加，以及一氧化氮和脂质过氧化的减少。人工授精后，DMA 和 DMSO 组的孵化率和生育率明显（P<0.05）高于 EG 组。结论是，含有 6%DMA 的冷冻保存液比 DMSO 或 EG 更能改善鸡解冻后精液的质量和生育能力。
