Al-Kass Z, Guo Y, Vinnere Pettersson O, Niazi A, Morrell J M
Swedish University of Agricultural Sciences (SLU), Clinical Sciences, SE 750 07 Uppsala, Sweden; Department of Surgery and Theriogenology, College of Veterinary Medicine, University of Mosul, Mosul, Iraq.
Swedish University of Agricultural Sciences (SLU), Clinical Sciences, SE 750 07 Uppsala, Sweden.
Anim Reprod Sci. 2020 Oct;221:106568. doi: 10.1016/j.anireprosci.2020.106568. Epub 2020 Aug 1.
Bacteria colonize stallion semen during collection and processing which may cause disease in inseminated females or negatively affect sperm quality during storage prior to insemination. Antibiotics are added to semen extenders to control the growth of these bacteria but may induce antimicrobial resistance. Research into alternatives to antibiotics for this purpose requires knowledge of which bacteria are present in semen. Not all bacteria in semen, however, can be identified by conventional microbiological techniques. The objectives of the study were to: i) determine which bacteria are present in stallion semen using metagenomics; and ii) investigate individual differences in bacterial content in semen from all stallions on one premises. Bacterial DNA was extracted from ejaculates from seven stallions (one ejaculate per stallion) and bacteria were identified using 16S sequencing. In total, 83 bacterial genera were identified, varying from 25 to 52 among different individuals. There was a negative correlation (r = -0.81212; P < 0.05) between the presence of Treponema spp. and Advenella spp. In conclusion, most of the bacteria present in stallion semen could be identified to genus level by 16S sequencing even when present at a low frequency. This method of identification may help to clarify individual variation in bacterial content and its potential effects on fertility.
在采精和精液处理过程中，细菌会在种马精液中定殖，这可能会导致授精母马患病，或者在授精前的精液储存过程中对精子质量产生负面影响。抗生素会添加到精液稀释液中以控制这些细菌的生长，但可能会诱导产生抗菌耐药性。针对此目的寻找抗生素替代品的研究需要了解精液中存在哪些细菌。然而，并非精液中的所有细菌都能通过传统微生物学技术鉴定出来。本研究的目的是：i）使用宏基因组学确定种马精液中存在哪些细菌；ii）调查同一养殖场所有种马精液中细菌含量的个体差异。从七匹种马的射精样本（每匹种马一个射精样本）中提取细菌DNA，并使用16S测序鉴定细菌。总共鉴定出83个细菌属，不同个体之间的细菌属数量从25个到52个不等。密螺旋体属和艾氏菌属的存在之间呈负相关（r = -0.81212；P < 0.05）。总之，即使种马精液中存在的大多数细菌频率较低，通过16S测序也能鉴定到属水平。这种鉴定方法可能有助于阐明细菌含量的个体差异及其对生育能力的潜在影响。
