Adjusted method of penis fixation during boar semi-automatic semen collection aiming to reduce bacterial contamination.

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.

Differential seminal plasma proteome signatures of boars with high and low resistance to hypothermic semen preservation at 5°C.

Background: Hypothermic storage at 5°C has been investigated as an alternative to promote the prudent use of antibiotics for boar artificial insemination doses. However, this temperature is challenging for some ejaculates or boars.

Objective: The present study aimed to identify putative biomarkers for semen resistance to hypothermic storage at 5°C by comparing the seminal plasma proteomes of boars with high and low seminal resistance to preservation at 5°C.

Determination of a cooling-rate frame for antibiotic-free preservation of boar semen at 5°C.

Hypothermic storage of boar semen provides the possibility to omit antibiotics from semen extenders so long as sperm quality is maintained and bacterial growth prevented. The objective of this study was to determine an optimal cooling-rate frame for boar semen preserved at 5°C in an antibiotic-free extender. Semen from eight boars extended in AndroStar® Premium was cooled from 30°C to 5°C using seven different cooling rates, ranging initially from 0.