title: Sperm penetration assay as an indicator of bull fertility.
abstract: To predict the fertility of frozen-thawed bull spermatozoa, a sperm penetration assay (SPA) using zona-free hamster oocytes was optimized, and the assay results were compared with data from field fertility expressed as the non-return rate (NRR). To increase sperm penetration, the spermatozoa were pre-incubated and coincubated with oocytes in media containing various concentrations of heparin (0 to 50 μg/ml). Coincubation with 10 μg/ml heparin showed the highest sperm penetration (P<0.05); it is considered to be the optimized SPA method. Sperm fertility index values obtained from WSPA were significantly correlated with the historic average NRR of 46 bulls (P<0.01). To determine the normal range for SPA, we established the lower limits of the sperm fertility index and set the cut-off value at 2.55, at which point the NRR was more than 70%, using the receiver operating characteristic curve. The overall accuracy for the 46 bulls was 95.7% (44/46) for both the low and high NRR, with a sensitivity of 95.5% (21/22) and a specificity of 95.8%. This protocol would make it easier to discriminate bulls according to their sperm fertilizing ability.
authors.affiliation: Department of Animal Science & Technology and BET Research Institute, School of Bioresource & Bioscience, Chung-Ang University, Gyeonggi-Do 456-756, Korea.
authors.forename: Yoo-Jin
authors.initials: YJ
authors.lastname: Park
authors.forename: El-Sayed A
authors.initials: el-SA
authors.lastname: Mohamed
authors.forename: Shin-Ae
authors.initials: SA
authors.lastname: Oh
authors.forename: Sung-Jae
authors.initials: SJ
authors.lastname: Yoon
authors.forename: Woo-Sung
authors.initials: WS
authors.lastname: Kwon
authors.forename: Heung-Ruil
authors.initials: HR
authors.lastname: Kim
authors.forename: Myeung-Sik
authors.initials: MS
authors.lastname: Lee
authors.forename: Kichoon
authors.initials: K
authors.lastname: Lee
authors.forename: Myung-Geol
authors.initials: MG
authors.lastname: Pang
mesh_terms: D000818:Animals; D017849:Animals, Inbred Strains; D002417:Cattle; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000662:veterinary; D006224:Cricetinae; D015925:Cryopreservation / Q000662:veterinary; D005260:Female; D006493:Heparin / Q000494:pharmacology; D007248:Infertility, Male / Q000175:diagnosis / Q000503:physiopathology / Q000662:veterinary*; D008297:Male; D008647:Mesocricetus; D009865:Oocytes / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D009994:Osmolar Concentration; D015203:Reproducibility of Results; D055101:Semen Analysis / Q000379:methods / Q000662:veterinary*; D012662:Semen Preservation / Q000009:adverse effects / Q000662:veterinary; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013075:Sperm Capacitation / Q000187:drug effects*; D013084:Sperm-Ovum Interactions / Q000187:drug effects; D013094:Spermatozoa / Q000166:cytology / Q000187:drug effects / Q000473:pathology / Q000502:physiology*
chemical_list: D006493:Heparin