Clinical Sciences, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden; Department of Surgery and Theriogenology, College of Veterinary Medicine, University of Mosul, Mosul, Iraq.
Clinical Sciences, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
Anim Reprod Sci. 2023 Mar;250:107200. doi: 10.1016/j.anireprosci.2023.107200. Epub 2023 Feb 16.
Although previous studies have examined the relationship between the sperm DNA fragmentation index and fertility in stallions, other aspects of chromatin structure or packaging and fertility have not been explored. In the present study, relationships between fertility and DNA fragmentation index, protamine deficiency, total thiols, free thiols and disulfide bonds in stallion spermatozoa were investigated. Ejaculates (n = 36) were collected from 12 stallions and extended to prepare semen doses for insemination. One dose from each ejaculate was sent to the Swedish University of Agricultural Sciences. Aliquots of semen were stained for flow cytometry with acridine orange for the Sperm Chromatin Structure Assay (DNA fragmentation Index, %DFI), with chromomycin A3 (CMA) for protamine deficiency, and with monobromobimane (mBBr) for detection of total and free thiols and disulfide bonds. Per season pregnancy rates after insemination were obtained. Mixed linear models were used to analyze data. Negative correlations were found between pregnancy rate and %DFI (r = -0.35, P < 0.03) and pregnancy rate and free thiols (r = -0.60, P < 0.0001). Furthermore, there were positive correlations between total thiols and disulfide bonds (r = 0.95, P < 0.0001), and protamine and disulfide bonds (r = 0.4100, P < 0.01986). Since chromatin integrity, protamine deficiency and packaging were all associated with fertility, a combination of these factors could be used as a biomarker of fertility when assessing ejaculates.
尽管先前的研究已经考察了精子 DNA 碎片化指数与种马生育力之间的关系，但染色质结构或包装的其他方面以及生育力尚未得到探索。在本研究中，研究了种马精子的生育力与 DNA 碎片化指数、鱼精蛋白缺乏、总巯基、游离巯基和二硫键之间的关系。从 12 匹种马采集精液（n=36）并进行扩展，以准备用于授精的精液剂量。每个精液样本的一份剂量被送到瑞典农业科学大学。用吖啶橙对精液进行流式细胞术染色，以进行精子染色质结构分析（DNA 碎片化指数，%DFI），用 Chromomycin A3（CMA）检测鱼精蛋白缺乏，用单溴乙内酰脲（mBBr）检测总巯基、游离巯基和二硫键。获得授精后每个季节的妊娠率。使用混合线性模型分析数据。妊娠率与%DFI（r=-0.35，P<0.03）和妊娠率与游离巯基（r=-0.60，P<0.0001）呈负相关。此外，总巯基和二硫键之间呈正相关（r=0.95，P<0.0001），鱼精蛋白和二硫键之间呈正相关（r=0.4100，P<0.01986）。由于染色质完整性、鱼精蛋白缺乏和包装都与生育力有关，因此在评估精液时，这些因素的组合可作为生育力的生物标志物。
