Utilization of bull fertility-associated antigen to improve the quality of frozen bull semen

BACKGROUND AND AIM: The implementation of artificial insemination (AI) is one of the strategies to use superior male semen optimally to improve the genetic quality of livestock. One of the factors that influence AI is a fertility-associated antigen (FAA). This research aimed to examine the effects of FAA extracted from the accessory sex glands of a bull from a slaughterhouse that was added in bull semen freezing medium to increase cattle (bull) fertilization. MATERIALS AND METHODS: This research used a randomized complete block design. It consisted of two research phases, namely, explorative and experimental phases. The first phase involved determining the FAA molecular weight using the SDS-PAGE method, and the second phase consisted of laboratory and field testing, including testing the quality of frozen semen supplemented with FAA extracted from the accessory glands of a bull’s genital organ from a slaughterhouse with various doses (0, 5, 10, and 15 μg in every 200 million progressively motile spermatozoa). RESULTS: The results showed that the percentages of bull sperm motility between the groups without and with the additional administration of FAA with a dose of 5 μg did not significantly differ. However, there was a difference between the groups without and with the additional administration of FAA with doses of 10 and 15 μg. After further testing, the highest percentage of sperm progressive motility occurred at a dose of 15 μg/200 million progressively motile spermatozoa (P3), which was equal to 2.59±46.88b (%). CONCLUSION: This research found that not all of the accessory glands (seminal vesicles) of bulls taken from the slaughterhouse contain the FAA. An FAA level between the accessory glands (seminal vesicles) of one cattle to another is different. The addition of the FAA protein from the accessory sex glands of a bull’s organ in cattle semen can improve fertility by increasing the percentage of viability, motility, intact plasma membrane of spermatozoa, and pregnancy rate of bulls and decreasing the sperm capacitation post-thawing.