Semen collection has an essential role in the initial bacterial load in boar ejaculates and extended semen. The study aimed to explore the efficacy of an adjusted penis fixation in a semi-automatic collection system on reducing bacterial contamination of ejaculates in two-boar studs with different scenarios. Historically, stud A had low levels of bacterial load in raw semen, while stud B had a high level of contamination. A total of 56 mature boars had their semen collected using two methods of penis fixation: (a) Traditional: The penis was fixed directly with the artificial cervix and transferred to the adjustable clamp; (b) Adjusted: The fixation was performed with one gloved-hand, and after exteriorization, the penis was gripped using the artificial cervix with the other gloved-hand and transferred to the adjustable clamp. The bacterial load (p = .0045) and the occurrence of ejaculates >231 CFU/ml (p = .0101) were reduced in the Adjusted compared to the Traditional method. Bacterial load was reduced when using the Adjusted method in stud B (p = .0011), which showed a greater occurrence of critical factors for bacterial contamination (p ≤ .0034). The Adjusted method reduced the occurrence of ejaculates >231 CFU/ml when the preputial ostium was dirty (p = .016) and the duration of semen collection was >7 min (p = .022) compared to the Traditional method. In conclusion, the Adjusted penis fixation was efficient in reducing bacterial load of ejaculates, mainly in boar stud B, which had high contamination challenges.

中文翻译：

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调整公猪半自动精液采集过程中阴茎固定方法以减少细菌污染

精液收集在公猪射精和延长精液中的初始细菌负荷中具有重要作用。该研究旨在探索半自动收集系统中调整后的阴茎固定对减少不同情况下两公猪种猪精液细菌污染的功效。从历史上看，种马 A 在原始精液中的细菌负荷水平较低，而种马 B 的污染水平很高。共有 56 头成年公猪采用两种阴茎固定方法采集精液： (a) 传统：阴茎直接用人工子宫颈固定，然后转移到可调节夹具上；(b) 调整：用一只戴手套的手进行固定，在外置后，用另一只戴手套的手使用人工子宫颈夹住阴茎并转移到可调节夹具上。细菌负荷（p  =  .0045) 并且与传统方法相比，调整后射精的发生率降低了 >231 CFU/ml ( p = .0101)。在螺柱 B ( p  = .0011) 中使用调整方法时，细菌负荷减少，这表明细菌污染的关键因素发生率更高 ( p  ≤ .0034)。 与传统方法相比，当包皮口脏 ( p  = .016) 且精液收集持续时间 >7 分钟 ( p = .022)时，调整后的方法减少了 >231 CFU/ml 的射精发生率。总之，调整后的阴茎固定可有效减少精液的细菌负荷，主要是在公猪种 B 中，其具有高污染挑战。