Long-term storage of boar seminal doses contaminated with Proteus vulgaris: A dose-dependent effect on sperm motility and sperm-bacteria interaction

• Published in: Animal reproduction science 2020-05, Vol.216, p.106349-106349, Article 106349
• Main Authors: Delgado-Bermúdez, Ariadna, Bonet, Sergi, Yeste, Marc, Pinart, Elisabeth
• Format: Article
• Language: English
• Subjects: Animals; Boar; Hydrogen-Ion Concentration; Male; Proteus vulgaris; Semen - microbiology; Semen - physiology; Semen Analysis - veterinary; Semen Preservation - veterinary; Semen quality; Sperm Motility; Sperm-bacteria interaction; Spermatozoa - physiology; Swine - physiology
• ISSN: 0378-4320; 1873-2232
• DOI: 10.1016/j.anireprosci.2020.106349

•P. vulgaris affects sperm motility from day 1 of refrigeration at ≥ 105 CFU mL−1.•P. vulgaris alters sperm viability from day 1 of refrigeration at ≥ 106 CFU mL−1.•P. vulgaris adheres to sperm surface from the first 24 h of refrigeration.•P. vulgaris shows high affinity towards mid and principal pieces of boar sperm. This study evaluated how Proteus vulgaris affects sperm quality and sperm-bacteria interaction in stored semen samples. A strain of P. vulgaris resistant to streptomycin, penicillin, lincomycin and spectinomycin was added to boar semen in doses of 103, 105, 106, 107 and 108 CFU/mL. A sample in which there was no addition of P. vulgaris was the negative control. Sperm quality was determined by evaluating sperm motility and morphology using the computer-assisted sperm analysis (CASA) system, and plasma membrane and acrosome integrity using flow cytometry at 0, 1, 2, 4, 6, 8 and 10 days of liquid-storage at 17 °C. At the same time points, pH, sperm agglutination, sperm-bacteria interaction and bacterial growth were also assessed. There was impaired sperm motility when the infective doses of P. vulgaris were equal to or greater than 105 CFU/mL with the effect being dose-dependent (P < 0.05). When infective doses of P. vulgaris were of 106 to 108 CFU/mL there were impairments of plasma membrane and acrosome integrity by Day 1 of storage (P < 0.05), and alkalinisation of the storing medium by Day 4 (P < 0.05). Bacterial adhesion increased when infective dose of P. vulgaris was greater and as duration of storage increased. P. vulgaris had a high affinity for the mid- and principal pieces of sperm cells. It is concluded there were alterations in sperm motility in samples infected with P. vulgaris that were associated with bacterial adhesion and medium alkalinisation.