Effect of refrigeration semen extender, refrigeration and storage at 4 degrees on buck semen microbiome. Capra hircus breed:Murciano-Granadina

Ejaculates present their own microbiota and a link between the microbiota and the sperm quality and fertility has been demonstrated. In this study, we explore the effects of the protocol for the preparation of goat buck refrigerated semen doses (that include dilution with a refrigeration extender and refrigeration to 4 degrees) and of storage period at temperatures below the body temperature on the semen microbiota. For the study, semen from six adult goat bucks from the Murciano-Granadina breed (24 ejaculates) was used and refrigerated to 4 degrees using a skimmed milk-based extender, being stored at this temperature for a maximum of 24 h. Samples were taken at different steps of the preparation: in the crude ejaculates (ejaculates), after the dilution with the refrigeration extender (diluted), immediately after reaching 4 degrees (Chilled 0 h) and in samples refrigerated to 4 degrees and stored at this temperature for 24 h (Chilled 24 h). Bacterial 16S rRNA sequencing was used to study the semen microbioma in the different steps of the refrigeration protocol as well as in the extender. In addition, sperm quality (motility and integrity of plasma and acrosomal membrane, and mitochondrial functionality) were also evaluated.

精液自身携带有独特的微生物群系（microbiota），且已有研究证实该微生物群系与精子质量及生育能力之间存在关联。本研究旨在探究公山羊冷藏精液制备流程（包括使用冷藏稀释液进行稀释以及将精液降温至4摄氏度）以及低于体温的储存时长对精液微生物群系的影响。本研究选用穆尔西亚-格拉纳达（Murciano-Granadina）品种的6只成年公山羊的精液样本（共24份精液），采用脱脂奶基稀释液将精液降温至4摄氏度，并在此温度下最长储存24小时。研究分别在制备流程的不同节点采集样本：原始精液样本（记为ejaculates）、经冷藏稀释液稀释后样本（记为diluted）、降温至4摄氏度后即刻样本（记为Chilled 0 h），以及降温至4摄氏度并储存24小时后的样本（记为Chilled 24 h）。本研究采用细菌16S rRNA测序技术，分析冷藏流程各节点样本及稀释液中的精液微生物群系（microbioma）。此外，本研究还对精子质量（包括精子活力、质膜与顶体膜完整性以及线粒体功能）进行了评估。