Motility of boar spermatozoa supplemented with homologous seminal plasma of high or low protein content after storage for three days

The effect of adding high or low protein content homologous seminal plasma to boar spermatozoa on the progressive motility of the spermatozoa after storage for three days, and at a 1 : 4 dilution ratio was investigated. A total of 32 ejaculates collected from four boars (eight ejaculates per boar) with high seminal plasma protein content (4%, HH-group) and 32 ejaculates collected from four boars (eight ejaculates per boar) with low seminal plasma protein content (2%, LL-group) were evaluated. The fresh ejaculate samples were centrifuged at 1000 g for 10 min at 4 °C to separate the spermatozoa from the seminal plasma. After centrifugation, one of the centrifuged spermatozoa samples was used to form an autologous fresh ejaculate sample, and another to form a homologous sample by adding low or high protein content seminal plasma from other boars. It was found that semen samples formed with spermatozoa from HH-group boars, supplemented with seminal plasma from LL-group, boars have significantly (P < 0.01) lower progressive motility (55%) after storage for 72 h than samples containing the boar's own (autologous) seminal plasma (65%). Conversely, when homologous seminal plasma with high protein content was added to the spermatozoa isolated from the boar ejaculate with low protein content in its seminal plasma, progressive motility significantly (P < 0.01) increased from 52% in samples with autologous seminal plasma, to 65% in samples with homologous seminal plasma. It was concluded that addition of homologous high protein content seminal plasma to the spermatozoa of boars with low protein content in their seminal plasma increases their progressive motility after storage for 72 h at a 1 : 4 dilution ratio. This could be a useful tool for increasing reproductive performance in lower fertility high genetic quality boars.